Systems and methods for monitoring an HVAC&R system employ a monitoring agent that uses observations of evaporator and condenser intake temperatures, evaporator discharge temperature, and a compressor input power parameter to learn operating characteristics of the HVAC&R system in newly maintained condition. Thereafter, the agent continuously or regularly computes a relative coefficient of performance (COP) for the system under subsequent observed ambient conditions, and relates the present instantaneous efficiency of the HVAC&R system under the observed ambient conditions to the instantaneous efficiency when the system was in newly maintained condition. The relative COP can be used to detect system degradation and quantify the energy usage and cost attributable to the degradation. The agent can take appropriate actions to prevent/minimize damage based on the degree of degradation detected, including shutting off power to the HVAC&R system. The monitoring agent can also be extended to other types of systems besides HVAC&R system.

A method for operating a linear compressor includes measuring a current induced in a motor of the linear compressor and calculating an observed current of the motor of the linear compressor using at least an electrical dynamic model for the linear compressor and a robust integral of the sign of the error feedback. The method also includes detecting a head crash within the linear compressor if an error between the observed current of the motor of the linear compressor and the measured current induced in the motor of the linear compressor is greater than a crash threshold.

A variable speed drive (VSD) can be used to vary the voltage-to-frequency ratio (V/f) supplied to a compressor motor of a heating, ventilation, air conditioning or refrigeration (HVAC&R) system to compensate for varying conditions in the HVAC&R system.

An exhaust heat reclaim system may include a diverter valve selectively connected in fluid communication to an exhaust vent tube and an exhaust delivery tube and configured to selectively divert hot exhaust fluid discharged from an exhaust of a power generation device to at least one of the exhaust vent tube and the exhaust delivery tube. The exhaust heat reclaim system may be a component of an HVAC system and be configured to discharge hot exhaust fluid onto a heat exchanger of the HVAC system, where the heat exchanger may be configured to promote heat transfer between the hot exhaust fluid and a refrigerant flowing through the heat exchanger of the HVAC system.

A motor driving apparatus and a home appliance including the same. The motor driving apparatus includes a temperature sensing unit to sense a compressor temperature, an inverter including a plurality of switching elements to convert a direct current (DC) voltage into an alternating current (AC) voltage and to supply AC voltage to a motor used to drive the compressor, and a controller to control the inverter. The controller performs control to apply motor preheating current for preheating of the motor during a first period before startup of the motor, and varies depending on the sensed temperature a time during which the motor preheating current is applied or a current application level. A reduction in power consumption during the preheating of the compressor is achieved.

A system includes a dynamic compressor and a controller having a processor and a memory. The compressor includes a first compressor stage having a first variable inlet guide vane (VIGV) and a second compressor stage having a second VIGV. The memory stores instructions that program the processor to operate the compressor at a current speed, a first position of the first VIGV, and a second position of the second VIGV to compress the working fluid, and to determine if a condition is satisfied. If the condition is not satisfied, the processor is programmed to continue to operate the compressor at the current speed, the first position of the first VIGV, and the second position of the second VIGV. If the condition is satisfied, the processor is programmed to change the second position of the second VIGV to a third position and maintain the first position of the first VIGV.

A method of controlling the temperature of a controller of an electric compressor for an air conditioner in a vehicle is provided, which prevents an excessive increase in temperature of the controller under the control of an output current of the controller. The method includes a temperature-determination stage of detecting the temperature of the controller and determining whether or not the detected temperature is equal to or lower than a reference temperature that is lower than a predefined target temperature by a specified number of degrees when an actuating signal of the air conditioner is generated in a switched-on stage of a vehicle. A current-control stage controls an output current of the controller to decrease the temperature until the detected temperature reaches the reference temperature or lower if the detected temperature is determined to be higher than the reference temperature.

A motor driving device and an air conditioner including the same are disclosed. The motor driving device includes a rectifier to rectify input AC power, a boost converter to boost power rectified by the rectifier, a capacitor to store a pulsating voltage from the boost converter, an inverter comprising a plurality of switching elements, the inverter transforming AC power, using a voltage across the capacitor, and outputting the transformed power to a motor, a regenerative power consuming unit arranged between the capacitor and the inverter, to consume regenerative power from the motor, and a switching driving unit to output a switching control signal to a switching element in the regenerative power consuming unit while outputting an operation control signal to an inverter controller when the voltage across the capacitor is equal to or higher than a predetermined voltage.

A motor drive apparatus includes a connection switching device that switches a connection state of windings of a first motor by switches; an inverter that applies an alternating-current voltage to the windings; a first control device that controls the inverter and the connection switching device; and a second control device that controls a second motor for an element that affects the first motor. Control by the first control device when switching includes a first stage of bringing an effective value of alternating current flowing through the windings close to zero compared to that before the connection state is switched; and a second stage of suspending output of the alternating-current voltage from the inverter. The second control device keeps the second motor running during the first and second stages, and the first control device switches the switches in the second stage.

Disclosed are systems that provide novel capabilities and component configurations for a climate system at a location, which can be a residential forced air cooling or heat pump, and the like. The disclosed system provides the ability for power to be provided to inherent system circuitry and components when there is no power input, which can be according to system needs, requirements, requests and/or other real-world events that cause such climate system to operate.