METHOD AND SYSTEM FOR CONTROLLING OPERATION OF AN INDUCER MOTOR OF A COMBUSTION SYSTEM

Abstract

Embodiments of the disclosure describe a method and a system for controlling an operation of an inducer motor of a furnace system. The method includes receiving an input comprising one or more of experimental data, field test data, and operational information associated with the furnace system along with associated environmental condition data. The method also include establishing a relationship associated with torque signals and motor speed of the inducer motor to a precise airflow rate based on the received input. The method further includes controlling the operation of the inducer motor based at least on the established relationship and a required mass flow rate of the air in the furnace system.

Claims

1. A method for controlling an operation of an inducer motor of a furnace system, comprising: receiving, by a control system connected to the inducer motor, an input comprising one or more of experimental data, field test data, and operational information associated with the furnace system along with associated environmental condition data; establishing, by the control system, a relationship associated with torque signals and motor speed of the inducer motor to a precise airflow rate based on the received input; and adjusting, by the control system, a Pulse Width Modulation (PWM) signal to operate the inducer motor based at least on the established relationship and a required mass flow rate of the air in the furnace system.

2. The method of claim 1, wherein the experimental data indicates a relation of one or more Pulse Width Modulation (PWM) signals corresponding to the torque signals of the inducer motor with a resulting rate of air flow at various operating conditions.

3. The method of claim 1, wherein the operational information associated with the furnace system comprises an operating state, a temperature of exhaust gas, a barometric pressure, and a time of operation.

4. The method of claim 1, wherein the field test data comprises one or more feedback on previous control operations of the inducer motor based on the experimental data and operational information.

5. The method of claim 1, further comprising: applying a correction factor to the PWM signal based on at least one of a temperature and a pressure to obtain a required mass flow rate.

6. The method of claim 1, further comprising: receiving sensor data from one or more flue gas temperature sensors of the furnace system; receiving user input corresponding to an altitude of the furnace system; identifying an average barometric pressure in the furnace system based on the received user input; and adjust, by the control system, a Pulse Width Modulation (PWM) signal to operate the inducer motor based at least on the established relationship and a required mass flow rate of the air in the furnace system.

7. A system for controlling an operation of an inducer motor of a furnace system, comprising: a control system connected to the inducer motor; the control system comprises at least one processor, the at least one processor configured to: receive an input comprising one or more of experimental data, field test data, and operational information associated with the furnace system along with associated environmental condition data; establish a relationship associated with torque signals and motor speed of the inducer motor to a precise airflow rate based on the received input; and adjust, by the control system, a Pulse Width Modulation (PWM) signal to operate the inducer motor based at least on the established relationship and a required mass flow rate of the air in the furnace system.

8. The system of claim 7, wherein the experimental data indicates a relation of one or more Pulse Width Modulation (PWM) signals corresponding to the torque signals of the inducer motor with a resulting rate of air flow at various operating conditions.

9. The system of claim 7, wherein the operational information associated with the furnace system comprises an operating state, a temperature of exhaust gas, a barometric pressure, and a time of operation.

10. The system of claim 7, wherein the field test data comprises one or more feedback on previous control operations of the inducer motor based on the experimental data and operational information.

11. The system of claim 7, wherein the at least one processor is further configured to: apply a correction factor to the PWM signal based on at least one of a temperature and a pressure to obtain a required mass flow rate.

12. The system of claim 7, wherein the at least one processor is configured to: receive sensor data from one or more flue gas temperature sensors of the furnace system; receive user input corresponding to an altitude of the furnace system; identify an average barometric pressure in the furnace system based on the received user input; and determine the required mass flow rate of the air based on one or more of the current mass flow rate of the air, identified average barometric pressure, the received sensor data, and molar gas composition.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] These and other features, aspects, and advantages of the disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[0021] FIG. 1 illustrates a perspective view of a furnace unit, according to one or more embodiments of the present disclosure;

[0022] FIG. 2 illustrates a simplified view of an inducer motor and fan assembly, according to one or more embodiments of the present disclosure;

[0023] FIG. 3 illustrates a schematic block diagram of a control system, according to one or more embodiments of the present disclosure;

[0024] FIG. 4 illustrates a graph depicting a relation of an airflow produced by an inducer with respect to a pressure drop of a combustion system, according to one or more embodiments of the present disclosure;

[0025] FIG. 5 illustrates a process flow depicting a method for controlling an operation of an inducer motor, according to one or more embodiments of the present disclosure;

[0026] FIG. 6A illustrates a graph indicating a mass flow rate, a gas temperature, and a volumetric flow rate at an inducer motor, according to a conventional technique;

[0027] FIG. 6B illustrates a graph indicating an excess air flow rate based on variance in the volumetric flow rate at the inducer motor, according to a conventional technique;

[0028] FIG. 6C illustrates a graph indicating the mass flow rate, the gas temperature, and the volumetric flow rate at the inducer motor, according to one or more embodiments of the present disclosure; and

[0029] FIG. 6D illustrates a graph indicating an excess air flow rate based on variance in the volumetric flow rate at the inducer motor, according to one or more embodiments of the present disclosure.

[0030] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help improve understanding of aspects of the disclosure. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the disclosure so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION

[0031] For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the various embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the disclosure relates.

[0032] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the disclosure and are not intended to be restrictive thereof.

[0033] Reference throughout this specification to an aspect, another aspect or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. Thus, appearances of the phrase in an embodiment, in another embodiment, some embodiments, one or more embodiments and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0034] The present disclosure provides a solution to eliminate the need for a pressure-measuring device to govern the flow of a mass of air or flue gas through an inducer motor of a furnace system. The solution characterizes the mass flow of air or flue gas going through the inducer and therefore, the solution, is more independent of other pressure drops, geometry changes, or restrictions and changes in the installed environment across seasons of operation. Moreover, the solution delivers a more accurate mass flow rate of air through the inducer compared to the conventional solutions. The benefit of such a system is to provide for a nominal operation of the furnace combustion air system which can prolong the efficient lifespan of the furnace and its components as well as remove uncertainty for installation and repair technicians.

[0035] In one or more embodiments, the present disclosure discloses a control system that utilizes data on an operating state, a timing of a giving state, a temperature of exhaust gases, and a barometric pressure as factors in determining suitable adjustments for the inducer's operating speed in order to achieve the desired mass flow rate of combustion air at a given time within the operating sequence.

[0036] In one or more embodiments, the control system utilizes experimental data, field test data, and operational information available to the control system to map ideal mass flow rates across the operating sequence (for example, pre-purge, stabilization, steady state, changing stages, or ignition, increasing/decreasing firing rate for a modulating system) and in given environmental conditions (for example, cold start, hot start, prior failed ignitions, safety limit devices reaching thresholds, etc.) The control system optimizes delivery of the combustion air to the burner system. Moreover, the control system provides a level of control over independent states of operating in the sequence that was previously not attainable by the conventional solutions/techniques.

[0037] The control system tightly controls the combustion air being delivered and may eliminate complexities in the design such are requiring various chokes and restrictions in the system in order to accommodate the range of installed conditions (orientation, altitude, vent size/length, etc.).

[0038] In one or more embodiments, the control system may be used in pre-mix burner systems for controlling mass flow and/or the potential for combustion resonance created during the ignition and stabilization stages of operation.

[0039] Moreover, the control system reduces excess combustion air level for in-shot burners while not compromising with reliability because of the tighter window of operation. The use of lower excess air levels will increase the thermal efficiency of the heat exchanger because it increases the flame temperature on one side of the exchanger.

[0040] The control system also eliminates difficulties with ignition at various conditions by accounting for the environmental conditions that lead to failed ignition attempts in the control methods.

[0041] Various embodiments supporting the above-mentioned advantages are elaborated in the following specification.

[0042] FIG. 1 illustrates a perspective view of a ducted, forced air gas-burning furnace unit 100 (hereinafter referred to as the furnace unit/system 100), according to one or more embodiments of the present disclosure. The furnace unit 100 includes a heat exchanger 102, a burner assembly 104, a fuel control system 106, an inducer motor and fan assembly 108, a furnace casing 110, a blower motor and fan assembly 112, and a control system 114. The furnace unit 100 may be installed within a building, such as a residential building, a commercial space, and the like.

[0043] The heat exchanger 102 may be configured to transfer heat generated by the combustion of gas to another medium, typically air or water, without direct contact between the two fluids. Primarily, the heat exchanger 102 may be configured to capture and transfer the thermal energy produced during the combustion of gases to warm the air/water for various applications.

[0044] The heat exchangers 102 of the furnace unit 100 may be implemented in various designs, such as, but not limited to, a shell-and-tube, a plate, and a finned-tube, clamshell, or tubular based on different applications. They are essential for the efficient operation of furnace unit 100, meeting different space and application requirements.

[0045] The burner assembly 104 may be configured to generate heat for the operation of the furnace unit 100. The burner assembly 104 may include components such as, a burner, a combustion chamber, a fuel supply system, an air supply system, an ignition system, and one or more safety control systems. The burner may be defined as the primary component of the burner assembly 104 that is responsible for combusting fuel. In one or more embodiments, the burner may be a gas burner configured to combust natural gas or methane to produce required heat to warn the fluid circulating through the furnace unit 100. The combustion chamber may correspond to an area where the fuel and air mixture is ignited and burned. The combustion chamber may be designed to accommodate the combustion process safely and efficiently. The fuel control system 106 may include fuel pipes, valves, and regulators that control the flow of fuel to the burner. The air supply system delivers air to the burner in a proportional manner that results in an efficient combustion. The ignition system is configured to initiate the combustion process by igniting the fuel-air mixture. The ignition system may implement ignition techniques such as, but not limited to, pilot lights, hot surface igniter, and spark igniters. The one or more safety control systems monitor and ensure safe operation of the burner assembly 104.

[0046] The fuel control system 106 is coupled to the burner assembly 104. In one or more embodiments of burner designs, the fuel control system 106 may be fully or partially coupled with an air intake system. The fuel control system 106 is configured to control the flow of combustible fuel within the furnace unit 100. A plurality of methods, mechanical or electromechanical, may be used within the fuel control system 106 to activate or meter the flow of fuel.

[0047] The inducer motor and fan assembly 108 is an essential component of the furnace unit 100 that is configured to create an air pressure in the combustion chamber to supply air to the combustion process and move air to ensure removal of the products of the combustion. The inducer motor and fan assembly 108 may be controlled in a manner to allow required air flow in or around the burner assembly 104. In one or more embodiments, the inducer motor and fan assembly 108 draws air into the burner assembly 104 within a range of air flows required for stable, efficient combustion and to keep the flame temperature within a range that allows long life of the burner assembly 104, the heat exchanger 102, and other surrounding components through avoidance of excessive heat transfer. The inducer motor and fan assembly 108 is used to maintain correct airflow and combustion conditions within the furnace unit 100.

[0048] The furnace casing 110 corresponds to an outer shell or enclosure of the furnace unit 100 that covers the various components (as disclosed herein) of the furnace unit 100. The furnace casing 110 provides protection to the internal components of the furnace unit 100, including the burner assembly 104, the heat exchanger 102, and other sensitive parts, from external elements such as dust, debris, and physical damage, prevents unsafe contact with hot surfaces or live electrical components, and creates separation of air streams for combustion, ducting, and ambient spaces. The furnace casing 110 may include insulation material to ensure heat remains within the furnace unit 100, improving energy efficiency by preventing heat loss. In one or more embodiments, the furnace casing 110 may also incorporate sound-dampening materials to reduce noise generated by the furnace unit 100.

[0049] The blower and fan assembly 112 is configured to circulate air through the furnace unit 100. The blower and fan assembly 112 ensures proper airflow and distribution of the conditioned air throughout the building and its ducts.

[0050] The control system 114 includes one or more processors/controllers and memory devices disposed communication with various sensors (not shown) and other components of the furnace unit 100 to ensure the desired operation of the furnace unit 100. The sensors may include, but not limited to, thermistors, flame sensors, pressure sensors, and so forth. The control system 114 may be configured to initiate, terminate, or adjust one or more operational modes of the one or more components of the furnace unit 100 based on predetermined limits or ranges. For instance, the control system 114 may be configured to control the inducer motor and fan assembly 108 to ensure the desired combustion and building duct airflow rate in the furnace unit 100, respectively.

[0051] The furnace unit 100 may also include various switches to control the operation of the various components of the furnace unit 100. Examples of such switches may include, but not limited to, a manual reset switch, a manual reset rollout switch, a main limit switch, a blower door and safety switch, and the like.

[0052] The furnace unit 100 may include other additional standard components, however a description of such components has been omitted for the sake of brevity.

[0053] FIG. 2 illustrates a simplified view of an inducer motor and fan assembly 108 (interchangeably referred to as the inducer motor 108 and/or inducer assembly 108), according to one or more embodiments of the present disclosure.

[0054] The inducer assembly 108 includes an inducer housing 202 which provide a sealed mechanism for containing the exhaust gases and comprises and inlet and outlet connection to conduit the gas. The inducer housing 202 may also contain other features and connections for the purpose of effectively moving the gas or connecting to other named or unnamed components. The inducer impeller 204 rotates within the inducer housing 202 in order to move the exhaust gases efficiently through the inducer assembly 108 adding both static and dynamic pressure to the gas. The inducer impeller is mounted to the shaft of the inducer motor assembly 206 which is configured to rotate the impeller 204 within the inducer housing 202 according to a control signal. In one or more embodiments, the control signal is a pulse width modulation (PWM) signal provided from the control system 114 indicating a torque or power level for system operation. The inducer motor 206 provides a tachometer feedback to the control system 114 to indicate the rotational speed of the inducer motor 206.

[0055] The inducer assembly 108 further includes a flue gas temperature sensor 210 configured to detect temperature of the flue gas within the inducer assembly 108. The flue gas temperature sensor 210 may generate output indicating the temperature of the exhausted gas from the furnace in all operating modes and sequences.

[0056] FIG. 3 illustrates a schematic block diagram of a control system 300, according to one or more embodiments of the present disclosure. In one or more embodiments, the control system 300 may correspond to the control system 114, as shown in FIG. 1.

[0057] The control system 300 may be configured to control one or more operations of the furnace system. In one or more embodiments, the control system 300 may be configured to control the operation of the burner assembly 104, the fuel control system 106, the inducer motor and fan assembly 108, and the blower motor and fan assembly 112. The control system 300 may include a processor/controller 302, an Input/Output (I/O) interface 304, one or more modules 306, a transceiver 308, and a memory 310.

[0058] In one or more embodiments, the processor/controller 302 may be operatively coupled to each of the I/O interface 304, the modules 306, the transceiver 308 and the memory 310. In one or more embodiments, the processor/controller 302 may be one or more general processors, digital signal processors, application-specific integrated circuits, field-programmable gate arrays, digital circuits, analog circuits, combinations thereof, or other now known or later developed devices for analyzing and processing data. The processor/controller 302 may execute a software program, such as code generated manually (i.e., programmed) to perform the desired operation.

[0059] The processor/controller 302 may be disposed in communication with one or more input/output (I/O) devices via the I/O interface 304.

[0060] In one or more embodiments, the memory 310 may be communicatively coupled to the at least one processor/controller 302. The memory 310 may be configured to store data, instructions executable by the at least one processor/controller 302. In one or more embodiments, the memory 310 may communicate via a bus within the control system 300. The memory 310 may include, but not limited to, a non-transitory computer-readable storage media, such as various types of volatile and non-volatile storage media including, but not limited to, random access memory, read-only memory, programmable read-only memory, electrically programmable read-only memory, electrically erasable read-only memory, flash memory, magnetic tape or disk, optical media and the like. In one example, the memory 310 may include a cache or random-access memory for the processor/controller 302. In alternative examples, the memory 310 is separate from the processor/controller 302, such as a cache memory of a processor, the system memory, or other memory. The memory 310 may be an external storage device or database for storing data. The memory 310 may be operable to store instructions executable by the processor/controller 302. The functions, acts or tasks illustrated in the figures or described may be performed by the programmed processor/controller 302 for executing the instructions stored in the memory 310. The functions, acts or tasks are independent of the particular type of instructions set, storage media, processor or processing strategy and may be performed by software, hardware, integrated circuits, firmware, micro-code and the like, operating alone or in combination. Likewise, processing strategies may include multiprocessing, multitasking, parallel processing, and the like.

[0061] In one or more embodiments, the modules 306 may be included within the memory 310. The memory 310 may further include a database 312 to store data. The one or more modules 306 may include a set of instructions that may be executed to cause the control system 300 to perform any one or more of the methods/processes disclosed herein. In one or more embodiments, the modules 306 may be configured to perform one or more operations of the processor 202 to achieve the desired objective of the present disclosure. The one or more modules 306 may be configured to perform the steps of the present disclosure using the data stored in the database 312, for controlling an operation of an inducer motor of a furnace system 100. In one or more embodiments, each of the one or more modules 306 may be a hardware unit which may be outside the memory 310. Further, the memory 310 may include an operating system 314 for performing one or more tasks of the control system 300, as performed by a generic operating system in the communications domain. The transceiver 308 may be configured to receive and/or transmit signals to and from an electronic device associated with the user. In one or more embodiments, the database 312 may be configured to store the information as required by the one or more modules 306 and the processor/controller 302 to perform one or more functions for controlling the operation of the inducer motor 108.

[0062] In one or more embodiments, the processor/controller 302 may be configured to receive an input comprising operational information associated with the furnace system 100 along with associated environmental condition data. In one or more embodiments, the experimental data produces a curve-fit model of a relation of one or more Pulse Width Modulation (PWM) signals corresponding to the torque signals of the inducer motor 108 with a resulting rate of air flow at various operating conditions. In one or more embodiments, the experimental data may indicate power characteristics, torque characteristics, an efficiency, temperature characteristics, vibration characteristics, start-up characteristics, and environmental characteristics associated with the inducer motor 108 in a controlled lab environment. The experimental data may be referred to quantitative and qualitative information gathered through systematic observation, measurement, and testing in controlled conditions. The experimental data is collected to analyze and understand the characteristics (for example, the power characteristics, the torque characteristics, the efficiency, the temperature characteristics, the vibration characteristics, the start-up characteristics, and the environmental characteristics) of the inducer motor 108. The power characteristics may correspond to a measure of power consumption of the inducer motor 108 under various operating conditions such as different speeds or loads. The torque characteristics may correspond to torque produced by the inducer motor 108 under different operating conditions, such as different speeds and varying loads. The efficiency may indicate a measure of an input power and an output power of the inducer motor 108 at different operating points. The temperature characteristics may indicate a change in temperature of the inducer motor 108 during operation. The start-up characteristics may correspond to an analysis of the start-up behavior of the inducer motor 108, including start-up time and current surge. The experimental data may include any additional information that indicates one or more operational characteristics of the inducer motor 108 in the controlled lab environment. In one non-limiting embodiment, the experimental data may include data collected in the controlled lab environment to determine the programming of the inducer motor 108 and the control system 300. Further, the operational information may include real-time operating data which is used to interpret the airflow and running states of the furnace system 100 and make appropriate adjustments along a pre-determined response based on programming of the controller.

[0063] The operational information associated with the burner system (for example, the furnace unit/system 100) may include information such as, but not limited to, an operating state, a temperature of exhaust gas, a barometric pressure, and a time of operation. The operating state may correspond to one of an ignition state, a start-up state, a normal operating state, a partly loaded operation state, a fully loaded operation state, a shutdown state, a failure state, and so forth.

[0064] In one or more embodiments, test field data may include one or more feedbacks on previous control operations of the inducer motor 108 based on the experimental data and operational information. In one or more embodiments, the test field data may correspond to the data collected by the processor/controller 302 during one or more previous operations of the inducer motor 108. Specifically, the test field data may refer to the information collected during real-world or operational testing of the inducer motor 108, in its intended environment. The test field data encompasses feedback on the performance and behavior of the inducer motor 108 during actual use, which may include operational insights derived from prior control operations, responses to varying conditions, and user interactions. The test field data may be utilized to assess the efficacy and reliability of the inducer motor 108 under practical scenarios and to refine control strategies based on real-time feedback.

[0065] In one or more embodiments, the processor/controller 302 may be configured to determine a relationship associated with torque signals and motor speed of the inducer motor 108 to a precise airflow rate based on the received input. For instance, the processor/controller 302 may determine different values of torque signals and motor speeds and the corresponding airflow rates in different operating conditions. The processor/controller 302 may analyze the received inputs including the experimental data, the test field data, and the operational information, to precisely identify the behavior of the inducer motor 108 under different operating conditions. In one non-limiting embodiment, the determined relationship may be represented as a multi-variable curve graph that adequately associates a pair of PWM torque and RPM to a precise airflow. The determined relationship may be stored in the memory 310. In one or more embodiments, the processor/controller 302 may be configured to fit the determined relationship to a multivariable curve that adequately associates a pair of PWM torque and RPM to a precise airflow. This enables the control system 300 to achieve the desired airflow for the furnace system 100 across a range of operating conditions, including gradual or rapid changes to the pressure drop of the heat exchanger or venting system and to compensate for installed variations in the same.

[0066] In one or more embodiments, the processor/controller 302 may be configured to control the operation of the inducer motor 108 based at least on the determined relationship and a required volumetric flow rate of the air in the furnace system 100. In one or more embodiments, the processor/controller 302 may be configured to adjust an input signal (for example, the PWM signal), based on the determined relationship, to operate the inducer motor 108 at a required motor speed to change a current volumetric flow rate of the air in the furnace system 100 to the required volumetric flow rate.

[0067] In one or more embodiments, the processor/controller 302 may be configured to receive sensor data from one or more flue gas temperature sensors of the furnace system. The sensor data may indicate the temperature of the flue/exhaust gas within the furnace system. Further, the processor/controller 302 may be configured to receive a user input corresponding to an altitude of the furnace system 100. The processor/controller 302 may be configured to identify an average barometric pressure, in the furnace system 100, based on the received user input. Thereafter, the processor/controller 302 may be configured to determine the required volumetric flow rate of the air based on one or more of the current volumetric flow rate of the air, identified average barometric pressure, the received sensor data, and molar gas composition. In one or more embodiments, the required flow rate may be preconfigured across an operating period. For example, an ignition stage may be fuel rich and then lean out over a determined period of time to reach the steady state operating conditions. Therefore, the required flow rate may be preconfigured based on the different operating states. In one or more embodiments, the required flow rate may be determined based on operations factors (for example, how cold is the ambient temperature as assumed by the flue gas temperature sensor, how long has it been since the furnace last fired, etc.).

[0068] In particular, the processor/controller 302 may be configured to adjust an operating speed of the inducer motor 108 based on the estimated relationship in order to achieve the desired mass flow rate of combustion air at a given time within the operating sequence. The operating sequence may include pre-purge, ignition, stabilization, steady-state, changing stages, or increasing/decreasing firing rate for a modulating system/furnace system 100 in a given environmental condition. The environmental condition may include, but not limited to, cold start, hot start, prior failed ignitions, safety limit devices reaching thresholds, etc.

[0069] The processor/controller 302 may use the determined relationship to maintain a desired mass flow rate within the furnace system 100 across a range of operating conditions. Examples of such operating conditions may include, but are not limited to, a vent length, furnace heat exchanger pressure drop, moisture, vent blockages, etc.

[0070] In one or more embodiments, the processor/controller 302 may receive an input indicating a requested volumetric flow rate ({dot over (V)}.sub.REQ) and control a combustion air fan (inducer) motor operation such that an actual volumetric flow rate ({dot over (V)}.sub.ACUTAL) is very nearly the same as V.sub.REQ.

[0071] In one or more embodiments, the processor/controller 302 may also consider the additional inputs such as the sensor data from the one or more flue gas temperature sensors (T.sub.flue) and user input to determine altitude information of the furnace system 100. The processor/controller 302 may then use the determined altitude information to estimate an average barometric pressure (P.sub.bar, avg) for the installed location (altitude) of the furnace system 100. Based on the estimated average barometric pressure (P.sub.bar, avg), the processor/controller 302 may accurately estimate the mass flow rate of air as required by the combustion system of the furnace system 100. In one or more embodiments, the processor/controller 302 may utilize molar gas in response to determining whether the composition of the gas travelling through the inducer assembly comprises a volume of combusted gas and air (flue gas) when the furnaces system is actively firing or standard atmospheric air based before or after the unit is firing. In one or more embodiments, when the control system 300 applies a control signal to the fuel control system 106 to maintain the flow of combustion gas to the system, and if a change in the inducer has a delay between the control signal and the meaningful inducer adjustment is beneficial, the control system will know the timings and can send an early or delayed signal to change the inducer operation.

[0072] In one or more embodiments, the processor/controller 302 may implement a closed-loop feedback system to adjust the PWM signal to the inducer system in order to adjust the operation of the inducer motor 108 to meet the requested mass flow, {dot over (m)}.sub.REQ, for the state of operation. The processor/controller 302 may also be configured to vary an ideal mass flow of combustion air within the furnace system 100 for varying the overall performance of the furnace system 100 across different operating and environmental conditions. The processor/controller 302 may further be configured to consider additional factor such as, a residual heat in the heat exchanger system (ex. a furnace fired 5 minutes ago or has been off for 3 hours) or a temperature of the air being used for combustion (ex. very cold attic or room temperature indoor air) on a given heating cycle to control the operation of the inducer motor 108 as required by the present disclosure.

[0073] Thus, the processor/controller 302 controls the operation of the induction motor 108 based on received data and thus eliminates the need of pressure-measuring devices to govern the mass of air within the furnace system 100. More specifically, the processor/controller 302 may be configured to characterize the mass flow of air going only through the inducer 108, therefore, the control operation is independent of other pressure drops, geometry changes, or restrictions. Accordingly, the processor/controller is able to deliver a more accurate mass flow rate of air through the inducer 108.

[0074] Further, the present invention contemplates a computer-readable medium that includes instructions or receives and executes instructions responsive to a propagated signal. Further, the instructions may be transmitted or received over the network via a communication port or interface or using a bus (not shown). The communication port may be a part of the processor/controller 302 or may be a separate component. The communication port may be created in software or may be a physical connection in hardware. The communication port may be configured to connect with a network, external media, the display, or any other components in the system, or combinations thereof. The connection with the network may be a physical connection, such as a wired Ethernet connection or may be established wirelessly. Likewise, the additional connections with other components of the control system 300 may be physical or may be established wirelessly. The network may alternatively be directly connected to the bus.

[0075] The processor/controller 302 may be configured to accurately control the combustion air being delivered to the furnace system 100 and may eliminate complexities in the design of the furnace system 100. Such design complexities may include requiring various chokes and restrictions in the furnace system 100 and/or in a venting system installed at the premises in order to accommodate the range of installed conditions.

[0076] For the sake of brevity, the architecture, and standard operations of the operating system 314, the memory 310, the database 312, the processor/controller 302, the transceiver 308, and the I/O interface 304 are not discussed in detail.

[0077] FIG. 4 illustrates a graph 400 depicting a relation of an airflow produced by an inducer with respect to a pressure drop of a combustion system, where one graph 402 shows the variation across the pressure drop and one line set 404 shows a more constant air flow according to one or more embodiments of the present disclosure. A line set of the graph 402 represents an operation of existing inducer motors where increased or decreased pressure drops through the furnace system 100 and associated combustion air and venting piping have significant effect on the delivered combustion air for the efficient operation of the furnace system 100. The line set 404 represents the effect of the present disclosure to produce a constant mass flowrate of combustion air through the furnace system 100 by the control system 300 which adjust the operation of the inducer assembly 108/202. Line sets 406 and 408 represent variations that would exists and will also be represented in FIG. 6 of the variations which would not be compensated for to achieve a constant mass flow without the methods described in the present disclosure.

[0078] FIG. 5 illustrates a process flow depicting a method 500 for controlling an operation of an inducer motor 108 of the furnace system 100, according to one or more embodiments of the present disclosure. The method 500 may be implemented by the control system 300 and/or the one or more processors 302.

[0079] At step 502, the method 500 includes for receiving an input comprising one or more of experimental data, field test data, and operational information associated with the furnace system 100 along with associated environmental condition data. In one or more embodiments, the control system 114, 300 may receive the input from a user via one or more input interfaces/devices (not shown) associated with the control system 114, 300. In one embodiment, the control system 114, 300 may be communicably coupled to an external device (not shown) to receive the input and/or the one or more of the experimental data, the field test data, and the operational information. In another embodiment, the experimental data, the field test data, and the operational information may be preconfigured at the memory (for example, the memory 310) associated with the control system 114, 300.

[0080] At step 504, the method 500 includes establishing a relationship associated with torque signals and motor speed of the inducer motor 108 to a precise airflow rate based on the received input. In one or more embodiment, the control system 114, 300 may be configured to process the received input to determine the relationship associated with torque signals and motor speed of the inducer motor 108. The control system 114, 300 may analyze one or more of the experimental data, the field test data, and the operational information to determine the relationship associated with the torque signals (PWM signals) and motor speed of the inducer motor 108 to obtain the precise airflow rate.

[0081] At step 506, the method 500 includes controlling the operation of the inducer motor based at least on the established relationship and a required mass flow rate of the air in the furnace system 100. In one or more embodiments, the control system 114, 300 may operate the inducer motor 108 at various speeds and pressure restrictions to generate a 3-D model which is capable to use PWM duty cycle and RPM of operation to describe a single volumetric airflow. In one or more embodiments, the control system 114, 300 and/or an external device (not shown) may be configured to generate a plurality of equations indicating such changes. In one or more embodiment, the plurality of equations for these curves may be programmed into the control system 114, 300 to use during operation and use a close loop feedback to increase or decrease the PWM duty cycle signal to the inducer motor 108 if the calculated volumetric airflow is higher or lower than the desired state. Thereafter, the control system 114, 300 may apply one or more correction factors for temperature and pressure (density) to get to a mass flow rate-based target instead of just the volumetric airflow. In one or more embodiment, the control system 114, 300 may interact with one or more sensors to apply the one or more correction factors. In one or more embodiment, the control system 114, 300 may interact with a motor driver circuit (not shown) associated with the inducer motor 108 to operate the inducer motor 108 as required.

[0082] While the above steps of FIG. 5 are shown and described in a particular sequence, the steps may occur in variations to the sequence in accordance with various embodiments of the disclosure. Further, the details related to various steps of FIG. 5, which are already covered in the description related to FIGS. 1-4 are not discussed again in detail here for the sake of brevity.

[0083] The disclosure ensures effective and efficient operation of the inducer motor and/or the furnace system by enable accurate air flow rate within the furnace system. The present disclosure control the operation of the inducer motor that is independent of pressure measuring devices, thereby provides a more reliable and effective control mechanism to achieve a desired air flow rate within the furnace system.

[0084] FIG. 6A illustrates a graph 602 indicating a mass flow rate, a gas temperature, and a volumetric flow rate at an inducer motor, according to a conventional technique. In the illustrated FIG. 6A, a graph line 602a indicates the mass flow rate, a graph line 602b indicates the gas temperature, and a graph line 602c indicates the volumetric flow rate at the inducer motor in accordance with a conventional technique. FIG. 6B illustrates a graph 604 indicating an excess air flow rate based on variance in the volumetric flow rate at the inducer motor, according to a conventional technique. FIG. 6C illustrates a graph 606 indicating the mass flow rate, the gas temperature, and the volumetric flow rate at the inducer motor, according to one or more embodiments of the present disclosure. In the illustrated FIG. 6C, a graph line 606a indicates the mass flow rate, a graph line 606b indicates the gas temperature, and a graph line 606c indicates the volumetric flow rate at the inducer motor 108, according to one or more embodiments of the present disclosure. FIG. 6D illustrates a graph 608 indicating an excess air flow rate based on variance in the volumetric flow rate at the inducer motor, according to one or more embodiments of the present disclosure. The graphs 602 and 604 clearly illustrate that the conventional technique fails to maintain a consistent excess air flow with change in the temperature or the pressure drop or the molar composition of the gas moving through the inducer motor 108. Whereas the graphs 606 and 608 indicates that the control system 300 is able to maintain a consistent excess air flow rate while considering factors such as, but not limited to, pressure drop, temperature change, molar composition, etc. In one or more embodiments, the control system 300 of the present disclosure increase/decrease the RPM of the inducer motor with change in the temperature, the pressure, or molar composition of the exhausted gas of the furnace system 100 to maintain the consistency in the excess air flow rate through the entire operating cycle. In particular, the control system 300 is configured to maintain a consistent volumetric flow rate of the excess air to have consistent mass flow of the air through the heating cycle. The control system 300 may be configured to maintain the excess air mass flow to a preconfigured level as required by the furnace system 100 for the desired operations. Moreover, the graphs 602 and 604 are result of systems that have fixed RPM operation, where the inducer motor stays at a constant speed while the combustion system warms up. This yields a varying mass flow that allows for a higher excess air level during ignition that leans out over time as the density of flue gas going through the heat exchanger varies with time (until steady state is reached) as the system warm up. Further, according to conventional technique, this mass flow of air changes when the mass flow of fuel is added in with the combustion air when the gas valve energizes, increasing the volumetric flow into the burners and heat exchangers. Since the mass flow of fuel doesn't change, the time-bound changes only affect the combustion air, resulting in the excess air changes as shown by the graphs 602 and 604. For example, the graph 604 indicates a change in the excess air across the cycle based on changes flue gas temperature as well as to the effects of variations in manufactured equipment and installed conditions that affect the volumetric flow rates. These factors can include the altitude, the pressure drop of the manufactured heat exchanger assembly, venting lengths and diameters, temporary blockages, etc. Since the volumetric flow rate of the gaseous fuel does not change across the cycle, the resulting changes in mass flow rate due to density change affect the combustion airflow and so exaggerates the change in excess air of the mixture. However, as illustrated by the graphs 606 and 608, the control system 300 provides a consistent mass flow rate of the system which accounts for the expected increase in mass flow rate when the gaseous fuel is added into the mixture when the gas valve opens. Additionally, graph 604 demonstrates the possible allowed variation in installed and manufactured conditions which require designing the equipment to ignite and operate at excess air levels consistent with the upper dotted line at t50 seconds and achieve efficient and reliable operation of the furnace at steady state excess air levels such as those along the bottom dotted line at t=600 seconds. This increases the cost and complexity of designing and manufacturing furnace systems that are robust and reliable. The graph 606 indicates the variation in volumetric flow rate as a result of the constant mass control method by the control system 300. The graph 608 shows the consistent excess air levels resulting from the consistent mass flow rates. Moreover, as different systems (for example, pre-mix burners) require different excess air flow levels at various stages of operation or environmental conditions, with the dynamic control over the RPM of the inducer motor, the control system 300 is able to provide the excess air flow level with such different variations across an operating cycle which is not represented here. Comparing to graph 604, the variations in the environment produce no change to the mass flow rate as a result of the control system 300.

[0085] While specific language has been used to describe the subject matter, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment.