MODULE AND METHOD FOR MONITORING POWER
20200120402 ยท 2020-04-16
Inventors
- Veliko Velikov (Woodbridge, CA)
- Voiko Loukanov (Woodbridge, CA)
- Ciprian Bacioiu (Woodbridge, CA)
- Kiril Delidjakov (Woodbridge, CA)
Cpc classification
H04L25/06
ELECTRICITY
H04Q2209/60
ELECTRICITY
H04Q9/00
ELECTRICITY
International classification
H04Q9/00
ELECTRICITY
H04L25/06
ELECTRICITY
Abstract
A module and method relating to measuring power supply to a load are described. The module includes a high pass filter corresponding to a first frequency range and configured to communicate a high frequency current signal. The module includes a low pass filter corresponding to a second frequency range configured to communicate a low frequency current signal. A signal combiner is configured to combine the low frequency current signal and the high frequency current signal, thereby generating a combined current signal. A voltage channel is configured to sense a voltage difference across the load and communicate a voltage signal corresponding to the voltage difference across the load. One or more processors in communication with a memory having non-transitory machine readable instructions stored thereon are configured to receive the combined current signal, receive the voltage signal, and determine a power metric based on the combined current signal and the voltage signal.
Claims
1. A power measurement module for measuring power supplied to a load via a power line, the module comprising: a high pass filter corresponding to a first frequency range configured to communicate a high frequency current signal from a first position on the power line; a low pass filter corresponding to a second frequency range configured to communicate a low frequency current signal from a second position on the power line; a signal combiner configured to combine the low frequency current signal and the high frequency current signal thereby generating a combined current signal; a voltage channel configured to sense a voltage difference across the load and communicate a voltage signal corresponding to the voltage difference across the load; and one or more processors in communication with a memory having non-transitory machine readable instructions stored thereon, the one or more processors configured to: receive the combined current signal; receive the voltage signal; and determine a power metric based on the combined current signal and the voltage signal.
2. The power measurement module of claim 1, wherein the high frequency current signal and the low frequency current signal are combined into a single current signal.
3. The power measurement module of claim 2, wherein the single current signal is digitized utilizing a first analog-to-digital converter (ADC), and wherein the voltage signal is digitized using a second ADC.
4. The power measurement module of claim 1, wherein the first range corresponds to a cutoff frequency and a maximum frequency.
5. The power measurement module of claim 1, wherein the second range corresponds to frequencies less than the cutoff frequency.
6. The power measurement module of claim 1, wherein the power measurement module comprises a housing, wherein the housing comprises a high frequency port, a low frequency port, a voltage port, and a patch panel port.
7. The power measurement module of claim 6, wherein the patch panel port provides a raw signal configured for display by an external scope.
8. The power measurement module of claim 1, wherein the power measurement module is configured to sample the power in the power line at a frequency corresponding to 10 MHz.
9. The power measurement module of claim 1, wherein the power measurement module is configured for power measurements associated with electric motors and inverters.
10. The power measurement module of claim 1, wherein the first position differs from the second position.
11. The power measurement module of claim 1, wherein the power metric includes one or more of: watt-hour (Wh), kilowatt-hour (kWh), joules (j), kilojoules (kj), power efficiency, kilo volt-ampere (KVA), kilo volt-ampere reactive (kVAR), amperes, voltage, root mean square (RMS) voltage, peak RMS voltage, real power P, reactive power Q, complex and apparent power, power factor, frequency, waveform, or phase angle.
12. The power measurement module of claim 1, wherein the one or more processors are further configured to output command and/or control signals in response at least in part to the high frequency current signal, the low frequency current signal, or the voltage channel signal.
13. A method for measuring power supplied to a load via a power line utilizing a power measurement module, the power measurement module comprising a high pass filter corresponding to a first frequency range; a low pass filter corresponding to a second frequency range; a signal combiner; a voltage channel; and one or more processors in communication with a memory having non-transitory machine readable instructions stored thereon, the method comprising: communicating, utilizing the high-pass filter, a high frequency current signal from a first position of the power line; communicating, utilizing the low-pass filter, a low frequency current signal from a second position of the power line; combining, utilizing the signal combiner, the low frequency current signal and the high frequency current signal, thereby generating a combined current signal; determining, utilizing the voltage channel, a voltage difference across the load; communicating a voltage signal corresponding to the voltage difference across the load; and determining, utilizing the one or more processors, a power metric based on the combined current signal and the voltage signal.
14. The method of claim 13, wherein the high frequency current signal in the low frequency current signal are combined into a single current signal
15. The method of claim 14, wherein the single current signal is digitized utilizing a first analog-to-digital converter (ADC), and wherein the voltage signal is digitized using a second ADC.
16. The method of claim 13, wherein the first range corresponds to a cutoff frequency and a maximum frequency.
17. The method of claim 13, wherein the second range corresponds to frequencies less than the cutoff frequency.
18. The method of claim 13, wherein the power measurement module comprises a housing, and wherein the housing comprises a high frequency port, a low frequency port, a voltage port, and a patch panel port.
19. The method of claim 18, wherein the patch panel port provides a raw signal configured for display by an external scope.
20. The method of claim 13, wherein the power measurement module is configured to sample the power in the power line at a frequency corresponding to 10 MHz.
21. The method of claim 13, wherein the power measurement module is configured for power measurements associated with electric motors and inverters.
22. Method of claim 13, wherein the first position differs from the second position.
23. The method of claim 13, wherein the power metric includes one or more of: watt-hour (Wh), kilowatt-hour (kWh), joules (j), kilojoules (kj), power efficiency, kilo volt-ampere (KVA), kilo volt-ampere reactive (kVAR), amperes, voltage, root mean square (RMS) voltage, peak RMS voltage, real power P, reactive power Q, complex and apparent power, power factor, frequency, waveform, or phase angle.
24. The method of claim 13, wherein the one or more processors are further configured to output command and/or control signals in response at least in part to the high pass filter signal, the low pass filter signal, or the voltage channel signal
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0009]
[0010]
[0011]
[0012]
[0013]
[0014]
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0015] The present invention will now be described in detail with reference to the drawings, which are provided as illustrative examples of the invention to enable those skilled in the art to practice the invention. Notably, the figures and examples below are not meant to limit the scope of the present invention to a single embodiment, but other embodiments are possible by way of interchange of some or all of the described or illustrated elements.
[0016] Moreover, where certain elements of the present invention can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present invention will be described, and detailed descriptions of other portions of such known components will be omitted so as not to obscure the invention. As used herein, the singular form of a, an, and the include plural references unless the context clearly dictates otherwise. As used herein, the statement that two or more parts or components are coupled shall mean that the parts are joined or operate together either directly or indirectly (i.e., through one or more intermediate parts or components, so long as a link occurs).
[0017] Embodiments described as being implemented in hardware should not be limited thereto, but can include embodiments implemented in software, or combinations of software and hardware, and vice-versa, as will be apparent to those skilled in the art, unless otherwise specified herein. In the exemplary embodiments described herein, an embodiment showing a singular component should not be considered limiting; rather, the invention is intended to encompass other embodiments including a plurality of the same component, and vice-versa, unless explicitly stated otherwise herein. Moreover, applicants do not intend for any term in the specification or claims to be ascribed an uncommon or special meaning unless explicitly set forth as such. Further, the present invention encompasses present and future known equivalents to the known components referred to herein by way of illustration.
[0018] As used herein, directly coupled means that two elements are directly in contact with each other. As used herein, fixedly coupled or fixed means that two components are coupled to move as one while maintaining a constant orientation relative to each other. As used herein, operatively coupled means that two elements are coupled in such a way that the two elements function together. It is to be understood that two elements operatively coupled does not require a direct connection or a permanent connection between them.
[0019] As used herein, the word unitary means a component is created as a single piece or unit. That is, a component that includes pieces that are created separately and then coupled together as a unit is not a unitary component or body. As employed herein, the statement that two or more parts or components engage one another shall mean that the parts exert a force against one another either directly or through one or more intermediate parts or components. As employed herein, the term number shall mean one or an integer greater than one (i.e., a plurality). Directional phrases used herein, such as, for example and without limitation, top, bottom, left, right, upper, lower, front, back, and derivatives thereof, relate to the orientation of the elements shown in the drawings and are not limiting upon the claims unless expressly recited therein.
[0020] One or more embodiments described herein relate to a power measurement module configured for wideband active and reactive power measurement. The power measurement module utilizes two current sensors, combined to form a single, highly accurate and wideband width channel for a current analog-to-digital converter (ADC). The two measurements provided by the two current sensors are combined during a power calculation in order to determine a power measurement of the load.
[0021] The frequency range of high precision current sensors is limited to below the real spectrum of the current signal. Power measuring modules having current sensors which are able to measure the high frequency current accurately are often unable to cover the DC range of the current. Accordingly, one or more embodiments described herein utilize two independent current sensors. The first independent current sensor may be configured for low frequencies from 0 Hz up to a cutoff frequency of the sensor. The second independent current sensor may be configured for high frequencies, such as from the cutoff frequency to a maximum frequency. One or more embodiments described herein may combine the signals from the two current sensors into a single channel. The signal channel may then be digitized. Accordingly, in one embodiment, the two current sensor signals are shaped by a low-pass filter (LPF) for the first current sensor and a high pass filter (HPF) for the second current sensor, which are added and applied to an analog-to-digital converter.
[0022] Conventional power measuring units on the market do not provide the sampling frequency of 10 MHz. This limitation inhibits the ability to analyze harmonics created during various control techniques used to control automotive electric motors.
[0023] Referring now to
[0024] As shown in
[0025] As further shown in
[0026] In some embodiments, PMM 100 may include low-pass filter 110. Low pass filter 110 may be configured to pass frequencies corresponding to frequencies less than the cutoff frequency. In one embodiment, the cutoff frequency may include 10 MHz. In another embodiment, the cutoff frequency may be between 10 MHz and 100 MHz. Low pass filter 110 may communicate a low frequency current signal from a second position of the power line, for example node 122. In some embodiments, LPF 110 may include a corresponding low frequency current connector, which is discussed in further detail below. As shown in
[0027] In some embodiments, PMM 100 may include signal combiner 112. As shown in
[0028] In some embodiments, PMM 100 includes voltage channel 116. Voltage channel may be 116 configured to sense a voltage potential difference, Vo, across load 104. In some embodiments, as discussed in further detail below, voltage channel 116 may operate with a corresponding high-voltage adapter connector (not shown). The high-voltage adapter connector may provide a connection for a PMM 100 high-voltage adapter. The adapter accepts voltages up to 1000 V and divides the voltage to pass a maximum of 5 V through the high-voltage adapter connector, for example.
[0029] Voltage channel 116 communicates Vo via voltage signal 117. In some embodiments, voltage signal 117 may be digitized utilizing ADC 118. As shown in
[0030] In some embodiments, PMM 100 includes CPU 120. CPU 120 may include one or more processor(s) and/or processing circuitry (not shown) that are configured to provide information processing and/or system control capabilities for PMM 100. In some embodiments, processors of CPU 120 may include one or more of a digital processor, an analog processor, a digital circuit designed to process information, an analog circuit designed to process information, a state machine, a field programmable gate array (FPGA), and/or other mechanisms for electronically processing information. or more processors in communication with a memory (not shown) having non-transitory machine readable instructions stored thereon. In some embodiments, CPU 120 may include one or more storage buffers, data registers, latches, CMOS inverters, interrupt/polling circuitry, timestamping circuitry, and/or other solid-state circuitry configured to receive and process raw data from sensors 120, 122, and communicate sensor data for processing and storage
[0031] In some embodiments, the one or more processors may be configured to receive the combined current signal, receive the voltage signal, and determine a power metric based on the combined current signal and the voltage signal. In some embodiments, the power metric may be expressed as a function of one or more of: watt-hour (Wh), kilowatt-hour (kWh), joules (j), kilojoules (kj), power efficiency, kilo volt-ampere (KVA), kilo volt-ampere reactive (kVAR), amperes, voltage, root mean square (RMS) voltage, peak RMS voltage, real power P, reactive power Q, complex and apparent power, power factor, frequency, waveform, phase angle., and the like.
[0032] One or more embodiments described herein provide for PMM 100 determining a power metric corresponding to the complete power spectrum of the power signal supplied by power source 102. Generally, the frequency range of high precision current sensors are limited to below the real spectrum of the current signal. However, by combining inputs from two independent current sensors (e.g., HPF 108 and LPF 110) the exemplary embodiments described herein are able to measure high sampling rates while maintaining a high accuracy, for example as depicted by Table 1 below.
TABLE-US-00001 TABLE 1 PMM Accuracies and Sampling Frequencies S. Frequency S. Frequency Connection Accuracy (continuous) (snapshot) CN400: 0.1% Equiv. 200 kHz 10 MHz Voltage (50samples@10 MHz avg.) CN500: Low 0.1% Equiv. 200 kHz 10 MHz Frequency (50samples@10 MHz avg.) Current CN501: High 0.1% Equiv. 200 kHz 10 MHz Frequency (50samples@10 MHz avg.) Current
[0033] In some embodiments, CPU 120 may be configured to receive digitized combined current signal 115 and digitized voltage signal 119 and determine a power metric based on digitized combined current signal 115 and digitized voltage signal 119. In some embodiments, prior to determining the power metric, CPU 120 may be configured to employ one or more signal processing techniques to condition signal 115, 119. For example, CPU 120 may be configured to implement a smoothing function on signals 115, 119 in order to remove high-frequency noise and low-frequency artifact that may be present in signals 115, 119. Utilizing two independent current sensors as discussed above, provides the ability to analyze harmonics created during various control techniques used to control automotive electric motors and/or other components. Accordingly, in one embodiment, PMM 100 may be configured for data acquisition of measurements associated with the evaluation of electric motors and inverters, for example.
[0034] Referring now to
[0035] In some embodiments, fasteners 210 may be positioned 7.5 (for example) inches from either edge of PMM housing 200. Fasteners 210 may be spaced apart 122.5 (for example) inches on the top and bottom of PMM housing 200. In some embodiments, PMM housing 200 may have a width of 40 (for example) inches, a height of 129 (for example) inches and a depth of 224 (for example) inches. In some embodiments, PMM housing 200 includes a depth of 172 (for example) inches not including connectors 202, 204, 206. In another embodiment, any other form of fastener, in any other position capable of coupling PMM housing 200 to a surface may be used. As such, the example dimensions described above are not intended to be limiting. The present device may have any dimensions that allow it to function as described herein.
[0036] In some embodiments, low-frequency current connector 202 may be configured to receive a low-frequency current signal (e.g., low-frequency current 105 of
[0037] In some embodiments, PMM housing 200 includes a high-frequency current connector 204. In one embodiment, high-frequency current connector 204, may include a BNC connection that may be used in conjunction with one or more Rogowski sensors. In one embodiment, the high-frequency current connector 204 channel performs signal conditioning of high-frequency signals.
[0038] In some embodiments, PMM housing 200 includes high voltage adapter connection 206. High voltage adapter connection 206 may be configured to accept voltages of up to 1000 V, for example. In some embodiments, high voltage adapter connection 206 may be configured to accept voltages of higher than 1000 V. High voltage adapter connection 206 may be configured to divide a high voltage input and output a maximum of 5 V, for example.
[0039] In some embodiments, PMM housing 200 includes a patch panel port (not shown). The patch panel port provides a raw signal to be displayed by an external scope (i.e. separate from PMM housing 200) and provides signal access to PMM 100. The external scope may include a spectrum analyzer, an oscilloscope, a signal generator, a voltmeter, an ohmmeter, and/or any other device configured to receive and display an electromagnetic signal. PMM 100 and PMM housing 200 may be configured to allow the signal to be plugged into an external device and then displayed via software or screen to the user. PMM 100, in accordance with one or more embodiments, includes a patch panel port that allows the raw signal to not only be displayed on software but also be available to be viewed with the external scope for comparison purposes. In some embodiments, PMM 100, 200 may include electrical specifications similar to or the same as Table 2 below.
TABLE-US-00002 TABLE 2 PMM Electrical Specifications Rating Min Typ. Max Unit Module Supply Voltage 15 +15 VDC Module Supply Current 3.4 A Operating Voltage, peak 15 +15 V Operating Current, peak 1 2 A Bus Termination Voltage 3.3 VDC Bus Termination Current 2 2.4 A Analog In voltage 10 +10 VDC Operating Temperature 5 25 40 C. Operating Humidity 80 %
[0040] Referring now to
[0041] In some embodiments, calculation unit 322, and/or trigger logic 320 may include one or more processor(s) and/or processing circuitry (not shown) that may be configured to provide information processing and/or system control capabilities for PMM 100, 200, 300. In some embodiments, processors may include one or more of a digital processor, an analog processor, a digital circuit designed to process information, an analog circuit designed to process information, a state machine, a field programmable gate array (FPGA), and/or other mechanisms for electronically processing information.
[0042] In some embodiments, memory 324, may include (not shown) non-transitory machine-readable instructions configured for executing the exemplary embodiments described herein. Non-transitory machine readable instructions may include program instructions in source code, object code, firmware, executable code or other formats for performing the exemplary embodiments described herein. In some embodiments, memory 124, 324 may include conventional computer system RAM (random access memory), ROM (read only memory), EPROM (erasable, programmable ROM), EEPROM (electrically erasable, programmable ROM), Flash memory, and/or magnetic or optical disks or tapes, and/or any other electronic storage medium capable of storing non-transitory machine readable instructions.
[0043] In some embodiments, trigger logic 320 may be configured to receive output signals from sensors 308, 310, 316 and employ trigger logic functionality. For example, trigger logic 320 may be configured to output command and/or control signals in response at least in part to high frequency current signal 109, low frequency current signal 111, or voltage channel signal 117. In some embodiments, an additional input signal may be reserved for including further functionality. In some embodiments, output signals 308, 310, and 316 may correspond to signals S0, S1, and S2, respectively (see Table 3 below).
TABLE-US-00003 TABLE 3 Trigger Logic 320 showing input logic and output command function Logic* S.sub.3 S.sub.2 S.sub.1 S.sub.0 Function 0 0 0 0 PMM Slice is instance 1 0 0 0 1 PMM Slice is instance 2 0 0 1 0 PMM Slice is instance 3 0 0 1 1 PMM Slice is instance 4 0 1 0 0 PMM Slice is instance 5 0 1 0 1 PMM Slice is instance 6 0 1 1 0 PMM Slice is instance 7 0 1 1 1 PMM Slice is instance 8 1 X X X Currently an invalid configuration**
[0044] In some embodiments, trigger logic 320 may receive four (4) input signals S0-S3. Each signal S0-S3 may be received eithers as a signal high (1) or signal low (0), or a do not care condition (x). Based on the particular logic received trigger logic 320 may actuate PMM slice instance 1-8 as shown above in Table 3. In this example, signal S3 may be utilized to execute additional command and control functionality. However, this example is not intended to be limiting.
[0045] In some embodiments, trigger logic 320 may output command and control operations corresponding to calculation unit 322, data memory 324 and/or snapshot data memory 326. Such command and control operations may be utilized for actuating memory and calculation functionality in accordance with one or more embodiments described herein. For example, trigger logic may input and output command signals operations, for example, as shown below in Table 3.
[0046] Referring now to
TABLE-US-00004 TABLE 4 Connector Part Numbers Name P/N Mating P/N Housing P/N CN1: JTAG 210-0544 Mates with connector that comes with the corresponding device programmer CN3: PMM 210-1560 Mates with CN on the main Connect PMM board CN400: High 210-0224 210-0013 Voltage Adapter P500: Low 210-1557 210-1556 N/A Frequency Current P501: High 210-1551 210-1554 N/A Frequency Current
[0047] In some embodiments, connector 400 (e.g., CN1: JTAG)may include pin connections according to:
TABLE-US-00005 1. GND; 2. +2.5 V; 3. GND 4. TMS 5. GND 6. TCK 7. GND 8. TDO 9. GND 10. TDI 11. GND 12. NC 13. GND 14. NC
[0048] CN400: High voltage adaptermay include pin connections according to:
TABLE-US-00006 1. 1. rTP401 2. 2. rTP402 3. 3. GND 4. 4. GND 5. 5. TP400 (U+ from adapter) 6. 6. TP401 (U from adapter) 7. 7. rTP400 8. 8. AVDDu 9. 9. +AVDDu 10. 10. GND
[0049] P500: Low-Frequency currentmay include pin connections according to:
TABLE-US-00007 1. 1. Current In 2. 2. Current Out 3. 3. Bus Positive 4. 4. Bus Negative
[0050] P501: High-Frequency currentmay include pin connections according to:
TABLE-US-00008 1. 1. Rogowski sensor 2. 2. GND
[0051] In some embodiments, CN1:JTAG may include a connection to allow access to a FPGA (e.g. 120, 320). CN3:PMM connect may include a connection to the main PMM board (e.g. board 600, described below). CN400: High Voltage Adapter may include a connection for a high voltage adapter, which may accept voltages of up to 1000V and divide the voltage to pass a maximum of 5V through the CN400 connection. In some embodiments, P500 low frequency current connector may include a 4-pin LEMO connector to supply power to the current sensing devices (e.g., 109, 110). In some embodiments, a voltage is created such that the input voltage does not exceed 1.1329V.
[0052] Referring now to
[0053] In some embodiments, PMM 100, 200, 300 may consist of multiple cards or slices that comprise, for example, look-up tables (LUTs) as shown above in Table 3. Individual slices may be configured as one or more programmable logic blocks. Programmable logic blocks may include arithmetic logic, registers, LUTs, latches, flip-flops, multiplexers, and the like. Elements organized in programmable logic blocks share connections in order to utilize fast carry chains, thereby increasing efficiency. In some embodiments, programmable logic blocks may be configured for measuring various qualitative values of PMM 100, 200, 300. For example, programmable logic blocks may measure voltage and current, analogue inputs, positions signals, and/or various other measurement corresponding to one or more embodiments described herein.
[0054] Referring now to
[0055] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word comprising or including does not exclude the presence of elements or steps other than those listed in a claim. In a device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The word a or an preceding an element does not exclude the presence of a plurality of such elements. In any device claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain elements are recited in mutually different dependent claims does not indicate that these elements cannot be used in combination.
[0056] Although the description provided above provides detail for the purpose of illustration based on what is currently considered to be the most practical embodiments, it is to be understood that such detail is solely for that purpose and that the disclosure is not limited to the expressly disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present disclosure contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.