Detection of current measurement gain errors in synchronous motor drives

Abstract

A system and method for detecting a current measurement gain error in a current measurement system are disclosed. The method includes: reading an output voltage signal; extracting a feature of the current measurement gain error from the output voltage signal; detecting whether the current measurement gain error exists based on the feature; and identifying a diagnostic voltage phase in which the current measurement gain error exists in response to detecting the presence of the current measurement gain error.

Description

Technical Field

[0001] The present disclosure relates to current measurement systems, and more particularly to systems and methods for detecting current measurement gain errors in current measurement systems. Background Art

[0002] A machine using a current measurement system may be affected by a current measurement gain error. Example causes of a current measurement gain error may include an inaccurate estimate of the shunt resistance, an operational amplifier gain, or some combination thereof. Often, the current measurement gain error may not be detected. Additionally, there may be one or more faulty current sensors that are the cause of the current measurement gain error in the current measurement system. Depending on the cause of the current measurement gain error, the severity of the current measurement gain error, and / or continued use of one or more faulty current sensors, the machine may experience undesirable effects. Summary of the invention

[0003] The present disclosure generally relates to detection of current measurement gain errors.

[0004] One aspect of the disclosed embodiment includes a system for detecting a current measurement gain error in a current measurement system. The system includes a processor and a memory. The memory includes instructions that, when executed by the processor, cause the processor to: read an output voltage signal; extract a feature of a current measurement gain error from the output voltage signal; detect whether a current measurement gain error exists based on the feature; and identify a phase in which the current measurement gain error exists in response to detecting the presence of the current measurement gain error.

[0005] Another aspect of the disclosed embodiment includes a method for detecting a current measurement gain error in a current measurement system. The method includes: reading an output voltage signal; extracting a feature of the current measurement gain error from the output voltage signal; detecting whether the current measurement gain error exists based on the feature; and identifying a phase in which the current measurement gain error exists in response to detecting the presence of the current measurement gain error.

[0006] Another aspect of the disclosed embodiment includes an electronic device. The electronic device includes a processor and a memory. The memory contains instructions that, when executed by the processor, cause the processor to: read an output voltage signal; extract a feature of a current measurement gain error from the output voltage signal; detect whether a current measurement gain error exists based on the feature; and identify a phase in which the current measurement gain error exists in response to detecting the presence of the current measurement gain error.

[0007] These and other aspects of the disclosure are disclosed in the following detailed description of the embodiments, the appended claims and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not in scale. Instead, the sizes of the various features are arbitrarily expanded or reduced for clarity.

[0009] Figure 1 A current measurement gain error detection and phase identification system according to the principles of the present disclosure is generally shown.

[0010] Figure 2 A block diagram for detecting and identifying current measurement gain errors in accordance with the principles of the present disclosure is generally shown.

[0011] Figure 3 A system in accordance with the principles of the present disclosure is generally shown.

[0012] Figure 4 is a flow chart generally illustrating a method for current measurement gain error detection and phase identification according to the principles of the present disclosure. DETAILED DESCRIPTION

[0013] The following discussion is directed to various embodiments of the disclosed subject matter. Although one or more of these embodiments may be preferred, the disclosed embodiments should not be interpreted or otherwise used to limit the scope of the present disclosure, including the claims. In addition, it will be understood by those skilled in the art that the following description has broad application, and the discussion of any embodiment is intended only as an example of that embodiment, and is not intended to imply that the scope of the present disclosure, including the claims, is limited to that embodiment.

[0014] Certain motion control applications (e.g., vehicles, ships, aircraft, drones, power equipment, field equipment, pumps, compressors, etc.) may include a synchronous motor drive that controls a synchronous motor that operates using closed-loop control. A current measurement system may be included in the closed loop to measure the current output by the synchronous motor. The current measurement system may be affected by current measurement gain errors.

[0015] Current measurement gain error may refer to the difference between a measured current and a true or actual current. The measured current may be measured by a current measurement system, and the commanded or reference current may be input by an operator of the machine or preconfigured for the machine. Example causes of current measurement gain error may include inaccurate estimation of shunt resistance, operational amplifier gain, excessive temperature, or some combination thereof.

[0016] Typically, the current measurement gain error may not be detected. In addition, there may be one or more faulty current sensors that are the cause of the current measurement gain error in the machine. Depending on the cause of the current measurement gain error, the severity of the current measurement gain error, and / or continued use of one or more faulty current sensors, the motor may experience undesirable effects. If not detected and / or uncorrected, such (multiple) current measurement gain errors may result in overall system performance degradation and / or motor failure. In addition, overall system degradation may affect the life of the synchronous motor and / or the attractiveness of a customer to purchase equipment including a synchronous motor. As a result, it is desirable to detect, identify, and mitigate current measurement gain errors.

[0017] Therefore, systems and methods, such as the systems and methods described herein, can be configured to address the above-mentioned problems by providing techniques for detecting and identifying current measurement gain errors and taking preventive measures based on the current measurement gain errors. In some embodiments, the systems and methods described herein can detect, learn, and compensate for the effects of current measurement gain errors on motor drives.

[0018] In some embodiments, the systems and methods described herein can be configured to provide techniques for real-time detection of current measurement gain errors in current measurement systems used in feedback-controlled synchronous motor drives. In addition, the systems and methods described herein can identify a specific phase that is experiencing current measurement gain errors. The systems and methods described herein can identify a specific current sensor that is malfunctioning and causing current measurement gain errors in that phase.

[0019] The systems and methods described herein may be configured to extract characteristics of a current measurement gain error using various mathematical models, detect whether a current measurement gain error exists based on the characteristics, and identify a phase of a synchronous motor where the current measurement gain error exists.

[0020] In some embodiments, the systems and methods described herein can be configured to take preventive measures based on the detected current measurement gain error, the phase identified as having the current measurement gain error, and / or the current sensor identified as causing the current measurement gain error. The preventive measures can include maintaining the synchronous motor drive in the same operating mode as the synchronous motor operation, or changing to an operating mode different from the operating mode in which the synchronous motor drive is currently operating. The systems and methods described herein can be configured to use different operating modes, such as current mode and voltage mode.

[0021] The disclosed embodiments provide at least the following benefits: including diagnostic techniques for detecting (static) gain errors in motor current measurement systems used for synchronous motor drives. The diagnostics are applicable to phase current measurement systems under any conditions and to both low-side current measurement systems and plug-in current measurement systems. The disclosed modeling of current measurement sensor gain errors and the extraction of features of current measurement sensor gain errors enable detection of current measurement sensor gain errors and identification of phases where current measurement sensor gain errors exist to identify faulty current sensors. The disclosed techniques are applicable to any motor drive with an alternating current (AC) motor and any current measurement architecture (both plug-in and low-side). A low-side current measurement system may refer to placing a current sensor between a low switch and ground of a phase bridge arm of a power converter. A plug-in current measurement system may refer to placing a current sensor in series with a motor phase winding so that the current flowing through the motor phase also flows through the current sensor. In addition, the disclosed embodiments may be implemented by a processor for real-time detection, identification and / or correction when operating a synchronous motor. The disclosed embodiments may also be implemented by a processor at the end of a production line (EOL) of a manufacturing plant.

[0022] Figure 1 A current measurement gain error detection and phase identification system 100 (referred to herein as the "system") in accordance with the principles of the present disclosure is generally shown. The system 100 may include a current controller 102, a current measurement gain error detector 104, a pulse width modulator 112, an inverter 114, a synchronous motor 116, a current sensor 118, and a current estimation component 120. It should be noted that fewer components or more components may be included in the system 100 as needed to perform the techniques disclosed herein, and the components depicted are for illustration purposes only. The synchronous motor 116 may generate a rotational force or a linear force for powering a motion control system, such as those described herein. The various components of the system 100 may be used as part of a synchronous motor drive 130 (e.g., the current controller 102, the current measurement gain error detector 104, the pulse width modulator 112, the inverter 114, or some combination thereof). The synchronous motor drive 130 may be an electronic device that utilizes and controls the electrical energy sent to the synchronous motor 116. The synchronous motor drive 130 may involve applying voltage to the synchronous motor 116 in different amounts and at different frequencies, thereby indirectly controlling the speed and / or torque of the synchronous motor 116 .

[0023] The current measurement system 140 may include a current estimation component 120 and a current sensor 118. Any suitable type of current sensor 118 capable of detecting current in a circuit may be used. The current sensor 118 may provide a signal indicative of the current to the current estimation component 120. The current estimation component 120 may be capable of receiving the signal indicative of the current and estimating the amount of current output by the synchronous motor 116.

[0024] The current controller 102 may receive a command current (I*) input by a user using a computing device or pre-programmed by default for the synchronous motor 116. In some embodiments, the current controller 102 is used in a feedback-controlled synchronous motor drive to track the command current with a minimum error. The current controller 102 transmits an output voltage signal to a pulse width modulator 112. The pulse width modulator 112 may control the time proportion when the output voltage signal is high compared to when the output voltage signal is low during a consistent time period. Controlling the time proportion when the output voltage signal is high or low may control the direction of the synchronous motor 116. The inverter 114 may be a voltage source inverter and may vary the frequency of the power supply fed to the synchronous motor 116 to control the speed of the synchronous motor 116. The synchronous motor 116 may receive an output voltage signal (V) as an input. The synchronous motor 116 may use the input to output an amount of current I, which may be equal to or different from the command current.

[0025] The current I output from the synchronous motor 116 can be sensed by the current sensor 118. The current estimation component 120 estimates the current is output to current controller 102. Thus, as depicted, system 100 uses a closed loop for current control.

[0026] The current controller 102 may receive the estimated current and compare the estimated current to the commanded current. If there is any change, the current controller 102 may transmit an output voltage signal (V*) that will cause the measured current to change. matches the command current I*. Thus, if the command current I* is assumed to be constant and the estimated current is equal to the command current I*, then the estimated current In order to maintain a constant measured current, the current controller 102 may pulse the output voltage signal, especially when there is a current measurement error.

[0027] The current measurement gain error detector 104 reads the output voltage signal from the current controller 102. The current measurement gain error controller 104 may include a demodulator 106, an error detector 108, and a phase isolator 110. The demodulator 106 may include a mathematical transformation or mathematical operation depending on the position of the synchronous motor. In some embodiments, the system 100 may include one or more bypass filters. The bypass filter may be configured to perform pre-filtering in a synchronous coordinate system before transformation, or to use an adaptive low-pass filter in a pseudo-steady-state coordinate system tuned (adaptively) according to a pulsation frequency twice the synchronous frequency.

[0028] As will be described, the error detector 108 can use a mathematical model to extract the characteristics of the current measurement gain error (e.g., in the event that a gain error exists). The error detector 108 receives the output voltage signal. The error detector 108 determines whether there is a current measurement gain error based on the output voltage signal. For example, if the error detector 108 determines that the output voltage signal includes only a constant portion and no sinusoidal portion, then the error detector 108 determines that there is no current measurement gain error represented in the output voltage signal. The sinusoidal portion may refer to a pulsating portion of the output voltage signal and may at least represent the characteristics of the current measurement gain error. If the error detector 108 determines that the output voltage signal includes a constant portion and a sinusoidal portion, then the current measurement gain error detector 108 determines that a parameter imbalance is detected because the sinusoidal portion represents the characteristics of the current measurement gain error.

[0029] The error detector 108 can use the mathematical transformation 106 to determine whether a current measurement gain error exists based on the presence of a feature. For example, the error detector 108 can determine the amplitude of the transformed voltage signal from 106 and compare the amplitude of the output voltage signal with a threshold. If the amplitude meets the threshold, the error detector 108 determines that a current measurement gain error exists. In addition, as will be described, the phase isolator 110 determines at least one phase of the synchronous motor in which a current measurement gain error exists. In some embodiments, the phase isolator 110 can determine that more than one phase includes a current measurement gain error. In addition, the phase isolator 110 can use this information to identify a specific current sensor 118 that contains a current measurement gain error.

[0030] The phase isolator 110 can use a mathematical model to identify additional information, where the additional information is related to why a particular current sensor 118 causes a current measurement gain error. The information may be related to an inaccurate estimate of the shunt resistance produced by the current sensor, the operational amplifier gain, or some combination thereof. The error detector 108 can output the magnitude of the current measurement gain error. The phase isolator 110 can output the phase(s) and / or the particular faulty current sensor 118 in which the current measurement gain error exists. A controller or circuit included in the system 100 can take preventive measures, such as changing or maintaining the operating mode of the synchronous motor drive 130, presenting a notification about the faulty current sensor 118 on a display of a computing device, etc.

[0031] The following discussion is related to the mathematical model used by the systems and methods described herein. After performing a reference coordinate system transformation from a static (abc) to a synchronous (dq0) coordinate system application, the systems and methods can utilize a model of the current measurement system. The measured motor phase current with gain error can be expressed as follows:

[0032] I am =(1+ΔK ga )I a

[0033] I bm =(1+ΔK gb )I b

[0034] I cm =(1+ΔK gc )I c

[0035] Equation 1.

[0036] Among them I x and I xm represents the actual current and measured current of phase x, while ΔK gx represents the gain error in the measurement. A reference frame transformation can be applied to Equation 1 to calculate the dq0 current estimate, where the reference frame transformation (e.g., Clarke-Park transformation) is expressed as follows:

[0037] h dq0 =Th abc

[0038]

[0039] Equation 2.

[0040] where h can represent voltage, current or flux connections, and β is the value of the three-phase machine. is a constant, and θ is the electrical position. The inverse Clarke-Park transform is expressed as follows:

[0041] h abc =T i h dq0

[0042]

[0043] Equation 3.

[0044] The Clarke-Park transform in Equation 2 is now applied to the measured motor phase current with gain error represented in Equation 1 to calculate the dq0 current estimate, which is expressed as follows:

[0045]

[0046] Equation 4.

[0047] ΔI gd =ΔK gs I d +ΔK gp (cos(2θ+φ gp )I d +sin(2θ+φ gp )I d )

[0048]

[0049] Equation 5.

[0050] ΔI gq =ΔK gs I q +ΔK gp (sin(2θ+φ gp )I d -cos(2θ+φ gp )I q )

[0051] Equation 6.

[0052]

[0053]

[0054]

[0055] Equation 7.

[0056] Equations 4 to 7 can be expressed in matrix form as follows:

[0057]

[0058] DC component AC component with unique current measurement gain error characteristics

[0059] Equation 8.

[0060] The mathematical model expressed in Equation 8 represents the sensing subsystem and represents what the current measured is when the closed-loop current control of the synchronous motor is not activated. In some embodiments, when the high-bandwidth current controller 102 is employed in a feedback current-controlled synchronous motor drive, the measured current may be approximately equal to or exactly equal to the command current or reference current, which may be expressed as follows:

[0061]

[0062]

[0063] Equation 9.

[0064] where ω d and ω q is the closed-loop bandwidth parameter setting of the current controller. When the bandwidth is high enough, the actual current value can be approximated as follows:

[0065]

[0066] Equation 10.

[0067] in and is the current command value.

[0068] In some embodiments, the commanded or actual motor voltage may then be calculated as follows:

[0069]

[0070] Equation 11.

[0071] By demodulating the dq voltage waveform, the ripple component (sinusoidal part) ΔV, which is unique to the current measurement gain error, can be extracted dq In some embodiments, a mathematical transformation may be applied to a voltage signal having an appropriate frequency of two per electric rotation as follows:

[0072]

[0073] Equation 12.

[0074] In some embodiments, for a non-salient machine, that is, L d =L q =L, the DC part of the transformed voltage signal is expressed as follows:

[0075]

[0076] Equation 13.

[0077] The transformed voltage signal may be further manipulated to determine a diagnostic voltage amplitude and a diagnostic voltage phase as follows:

[0078]

[0079] Equation 14.

[0080] in and

[0081] Using a mathematical model including the equations described herein, current measurement gain errors can be detected by comparing the DC signal to an appropriate predefined threshold.

[0082] Figure 2 A block diagram 200 for detecting and identifying a current measurement gain error in accordance with the principles of the present disclosure is generally shown. The block diagram 200 includes a block 202 for demodulation, a block for a current measurement gain error detector 204, and a fault phase identifier 206. The current measurement gain error detector 204 includes an amplitude and phase calculation block 208 and a gain error detector block 210. Blocks 202, 204, and 206 may be performed by the demodulator 106, the error detector 108, and the phase isolator 110, respectively.

[0083] The demodulation block 202 may receive the final synchronous frame voltage (eg, output voltage signal) from the current controller 102. After performing filtering to extract the diagnostic voltage V u and V u Afterwards, the demodulation block 202 may apply Equation 12 to the final synchronous frame voltage. The amplitude and phase calculation block 208 may calculate the diagnostic voltage amplitude V m , as described in Equation 14, which contains information that there is a current measurement gain error. The gain error detector block 210 can compare the diagnostic voltage amplitude with a predetermined threshold to check whether it exceeds the threshold. The motor speed can also be used using Equation 14 resistance and inductance The estimated value and current command value amplitude For example, when the current command value is above a predetermined current threshold, the diagnostic voltage amplitude may be compared to the threshold. If the diagnostic voltage amplitude meets the threshold, the gain error detector block 210 may output a current measurement gain error indicator U cm , which indicates that there is a current measurement gain error in one or more motor phases.

[0084] The fault phase identifier block 206 may receive the diagnostic voltage phase signal from the magnitude and phase calculation block 208 and utilize the diagnostic voltage phase signal to identify the specific motor phase P where the current measurement gain error exists. cm (e.g., A, B, or C in a three-phase synchronous motor). The faulty phase identifier block 206 can identify a particular current sensor 118 containing a current measurement gain error based on the diagnostic voltage phase. When a current measurement gain error is detected by the gain error detector 210, the faulty phase identifier block 206 uses the diagnostic voltage phase φ together with the current angle command value α * And resistor and inductance The estimated value of (as described in Equation 14) is obtained by dividing the gain error phase identifier signal P cm Set to A, B, C, or M to determine whether a single motor phase (of phases A, B, C) contains a gain error or whether multiple phases have gain errors simultaneously, where M indicates simultaneous gain errors in multiple phases. In the event of a single phase imbalance, the faulty phase identifier block 206 identifies the specific phase. The gain error phase identification logic is as follows:

[0085]

[0086] in Represents φ gp The estimated value of And φ w is the phase angle tolerance window for gain error phase identification. Note that the diagnostic voltage phase becomes equal to 0, φ when the imbalance is in phase A, B, and C, respectively. 0 、-φ 0 This can be determined by setting the value of the gain error in any single phase to a non-zero value and setting the other deviations to zero. For example, if the ΔK in Equation 5 is gb Non-zero and ΔK ga and ΔK gc is zero, then the phase angle φ gp becomes φ 0 Similar calculations can be performed for other phases using Equation 5.

[0087] Figure 3A controller system 300 in accordance with the principles of the present disclosure is generally shown. The controller system 300 includes a current measurement gain error detector 104 communicatively coupled to a memory 302. The current measurement gain error detector 104 may include a processor. The processor may include any suitable processor, such as those described herein. The memory 302 may store instructions that, when executed by the current measurement gain error detector 104, cause the current measurement gain error detector 104 to at least perform the techniques disclosed herein. In particular, when executed by the current measurement gain error detector 104, the computer instructions may cause the current measurement gain error detector 104 to perform the operations of the method 400, as described below with reference to Figure 4 As further described, the controller system 300 may be communicatively coupled to a computing device 304 . The computing device 304 may include a processor, a memory, a network interface, and / or a display. In some embodiments, a display of the computing device 304 may present a notification received from the current measurement gain error detector 104 .

[0088] Figure 4 4 is a flow chart generally illustrating a method 400 for current measurement gain error and phase identification according to the principles of the present disclosure. At 402, the method 400 reads an output voltage signal. For example, the current controller 102 may generate an output voltage signal. At 404, the method 400 extracts a feature of the current measurement gain error from the output voltage signal. In some embodiments, the output voltage signal may include only a constant portion, and in some embodiments, the output voltage signal may include a constant portion and a sinusoidal portion. If the output voltage signal includes only a constant portion, then there may be no current measurement gain error because the sinusoidal portion of the output voltage signal represents a pulsation that contains a feature of the current measurement gain error. Therefore, when the output voltage signal includes a constant portion and a sinusoidal portion, the sinusoidal portion is extracted as a feature of the current measurement gain error. The sinusoidal portion may correspond to a pulsating portion of the output voltage signal and may be generated due to the current controller 102 maintaining a measured current and / or an estimated current that contains a current measurement gain error equal to a command current.

[0089] At 406, the method 400 detects whether there is a current measurement gain error from the output voltage signal. That is, if the characteristics of the current measurement gain error are extracted, the method 400 determines the diagnostic voltage amplitude and compares the amplitude with the threshold. In some embodiments, when comparing with the threshold, the method 400 can use Equation 14. If the diagnostic voltage amplitude meets the threshold, the method 400 detects that there is a current measurement gain error. If the diagnostic voltage amplitude does not meet the threshold, the method 400 does not detect that there is a current measurement gain error.

[0090] At 408, in response to detecting the presence of a current measurement gain error, method 400 identifies a diagnostic voltage phase in which the current measurement gain error exists. Method 400 can use equation 14 to determine the diagnostic voltage phase, and then use the diagnostic voltage phase to identify a specific current sensor that has a fault. Therefore, method 400 can identify a current sensor 118 containing a current measurement gain error based on the diagnostic voltage phase. For example, various different current sensors 118 can measure various different phases. Method 400 can determine the operating mode in which the synchronous motor drive is to operate based on information related to the current sensor 118 that causes the current measurement gain error. Using one or more of the above equations, method 400 can provide information about the occurrence of a current sensor fault in a low-side current measurement system and a direct current measurement system.

[0091] This information may indicate that there has been an inaccurate shunt resistance estimate, operational amplifier gain, overheat temperature, or some combination thereof. Since some current measurement gain errors do not adversely affect the machine under certain operating conditions, method 400 may choose to continue operating in the same operating mode (e.g., voltage mode or current mode) in which the motor drive is currently operating. However, in some embodiments, method 400 may choose to change the operating mode to an operating mode (e.g., voltage mode or current mode) that is different from the operating mode in which the motor drive is currently operating. In some embodiments, method 400 may present a notification on a computing device used by a user, indicating that the identified current sensor 118 is faulty and instructing the operator to inspect, repair, and / or replace the faulty current sensor 118.

[0092] In some embodiments, a system for detecting a current measurement gain error in a motor drive includes a processor and a memory containing instructions. The instructions, when executed, cause the processor to read an output voltage signal, extract a characteristic of a current measurement gain error from the output voltage signal, detect whether a current measurement gain error exists based on the characteristic, and identify a phase in which the current measurement gain error exists in response to detecting the presence of the current measurement gain error.

[0093] In some embodiments, in response to identifying a phase in which a current measurement gain error exists, the instructions further cause the processor to identify a current sensor that causes the current measurement gain error based on the phase. In some embodiments, the instructions further cause the processor to determine an operating mode in which the synchronous motor drive is to operate based on information related to why the current sensor causes the current measurement gain error, and cause the synchronous motor drive to operate in the operating mode. In some embodiments, the information includes an inaccurate estimate of the shunt resistance, an operational amplifier gain, or some combination thereof. In some embodiments, the operating mode is an operating mode that is the same as the operating mode in which the motor drive is currently operating. In some embodiments, the operating mode is an operating mode that is different from the operating mode in which the motor drive is currently operating. In some embodiments, in order to detect whether a current measurement gain error exists based on a feature, the instructions further cause the processor to determine whether the amplitude of the output voltage signal meets a threshold.

[0094] In some embodiments, a method for detecting a current measurement gain error in a motor drive includes: reading an output voltage signal; extracting a characteristic of the current measurement gain error from the output voltage signal; detecting whether the current measurement gain error exists based on the characteristic; and identifying a phase in which the current measurement gain error exists in response to detecting the presence of the current measurement gain error.

[0095] In some embodiments, in response to identifying a phase in which a current measurement gain error exists, the method further includes identifying a current sensor causing the current measurement gain error based on the phase. In some embodiments, the method further includes determining an operating mode in which the synchronous motor drive is to operate based on information related to why the current sensor causes the current measurement gain error, and operating the synchronous motor drive in the operating mode. In some embodiments, the information includes an inaccurate estimate of the shunt resistance, an operational amplifier gain, or some combination thereof. In some embodiments, the operating mode is the same operating mode as the operating mode in which the motor drive is currently operating. In some embodiments, the operating mode is a different operating mode from the operating mode in which the motor drive is currently operating.

[0096] In some embodiments, an electronic device includes a processor and a memory. The memory includes instructions that, when executed by the processor, cause the processor to read an output voltage signal, extract a characteristic of a current measurement gain error from the output voltage signal, detect whether a current measurement gain error exists based on the characteristic, and identify a phase in which the current measurement gain error exists in response to detecting the existence of the current measurement gain error.

[0097] In some embodiments, in response to identifying a phase in which a current measurement gain error exists, the instructions further cause the processor to identify a current sensor that causes the current measurement gain error based on the phase. In some embodiments, the instructions further cause the processor to determine an operating mode in which the synchronous motor drive is to operate based on information related to why the current sensor causes the current measurement gain error, and cause the synchronous motor drive to operate in the operating mode. In some embodiments, the information includes an inaccurate estimate of the shunt resistance, an operational amplifier gain, or some combination thereof. In some embodiments, the operating mode is the same operating mode as the operating mode currently being operated by the motor drive. In some embodiments, the operating mode is a different operating mode than the operating mode currently being operated by the motor drive.

[0098] The above discussion is intended to illustrate the principles and various embodiments of the present invention. Once the above disclosure is fully understood, many changes and modifications will become apparent to those skilled in the art. The following claims are intended to be interpreted as covering all such changes and modifications.

[0099] The word "example" is used herein to mean serving as an example, instance or illustration. Any aspect or design described herein as an "example" is not necessarily to be interpreted as being more preferred or more advantageous than other aspects or designs. Instead, the use of the word "example" is intended to present concepts in a specific way. The term "or" as used in this application is intended to represent an inclusive "or" rather than an exclusive "or". That is, unless otherwise specified or clear from the context, "X includes A or B" is intended to represent any one of the natural inclusive arrangements. That is, if X includes A; X includes B; or X includes both A and B, "X includes A or B" is satisfied in any of the above cases. In addition, unless otherwise specified or clear from the context to refer to the singular form, the articles "one" and "an" as used in this application and the appended claims should generally be interpreted as referring to "one or more". In addition, unless so described, the use of the term "one embodiment" or "one embodiment" throughout the text is not intended to represent the same embodiment or embodiment.

[0100] The embodiments of the systems, algorithms, methods, instructions, etc. described herein may be implemented in hardware, software, or any combination thereof. The hardware may include, for example, a computer, an intellectual property (IP) core, an application specific integrated circuit (ASIC), a programmable logic array, an optical processor, a programmable logic controller, microcode, a microcontroller, a server, a microprocessor, a digital signal processor, or any other suitable circuit. In the claims, the term "processor" should be understood to include any of the aforementioned hardware, alone or in combination. The terms "signal" and "data" are used interchangeably.

[0101] As used herein, the term module may include a packaged functional hardware unit designed for use with other components, an instruction set executable by a controller (e.g., a processor executing software or firmware), a processing circuit configured to perform a specific function, and an independent hardware or software component that interfaces with a larger system. For example, a module may include an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a circuit, a digital logic circuit, an analog circuit, a combined discrete circuit, a gate, and other types of hardware or a combination thereof. In other embodiments, a module may include a memory that stores instructions executable by a controller to implement the features of the module.

[0102] Furthermore, in one aspect, for example, the systems described herein can be implemented using a general purpose computer or general purpose processor with a computer program that, when executed, implements any of the corresponding methods, algorithms, and / or instructions described herein. Additionally or alternatively, for example, a special purpose computer / processor can be utilized that can include other hardware for implementing any of the methods, algorithms, or instructions described herein.

[0103] In addition, all or part of the embodiments of the present disclosure may take the form of a computer program product that is accessible from, for example, a computer usable medium or a computer readable medium. A computer usable medium or a computer readable medium may be any device that, for example, may tangibly contain, store, transfer, or transmit a program for use by or in conjunction with any processor. The medium may, for example, be an electronic, magnetic, optical, electromagnetic, or semiconductor device. Other suitable media are also available.

[0104] The above embodiments, implementations and aspects have been described to allow easy understanding of the invention and are not intended to limit the invention. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which should be given the broadest meaning to cover all such modifications and equivalent schemes as permitted by law.

Claims

1. A system for detecting a current measurement gain error in a current measurement system, the system include: processor; as well as a memory comprising instructions that, when executed by the processor, cause the processor to: Read the output voltage signal; Using a mathematical model of a closed-loop current control system, wherein the mathematical model includes a current measurement gain error, the current measurement gain error at least including characteristics of a pulsating voltage signal having a frequency of twice per electric revolution; performing a mathematical transformation using the mathematical model to demodulate the output voltage signal to extract characteristics of the current measurement gain error; detecting whether the current measurement gain error exists based on the characteristic; and In response to detecting the presence of the current measurement gain error, a motor phase is identified in which the current measurement gain error exists.

2. The system according to claim 1, in, In response to identifying a motor phase having the current measurement gain error, the instructions further cause the processor to identify a current sensor causing the current measurement gain error based on the motor phase.

3. The system according to claim 2, in, The instructions further cause the processor to: determining an operating mode in which a synchronous motor drive is to operate based on information about the current sensor causing the current measurement gain error; and The synchronous motor drive is operated in the operating mode.

4. The system according to claim 3, in, The information includes an inaccurate estimate of the shunt resistance, the operational amplifier gain, or some combination thereof.

5. The system according to claim 3, in, The operating mode is a current operating mode.

6. The system according to claim 3, in, The operation mode is a voltage operation mode.

7. The system according to claim 1, in, To detect whether the current measurement gain error exists based on the characteristic, the instructions further cause the processor to determine whether a diagnostic voltage magnitude of the output voltage signal satisfies a threshold.

8. A method for detecting a current measurement gain error in a current measurement system, the method include: Read the output voltage signal; Using a mathematical model of a closed-loop current control system, wherein the mathematical model includes a current measurement gain error, the current measurement gain error at least including characteristics of a pulsating voltage signal having a frequency of twice per electric revolution; performing a mathematical transformation using the mathematical model to demodulate the output voltage signal to extract characteristics of the current measurement gain error; detecting whether the current measurement gain error exists based on the characteristic; and In response to detecting the presence of the current measurement gain error, a motor phase is identified in which the current measurement gain error exists.

9. The method according to claim 8, further comprising: include: In response to identifying the motor phase where the current measurement gain error exists, a current sensor causing the current measurement gain error is identified based on the motor phase.

10. The method according to claim 9, further comprising: include: determining an operating mode in which a synchronous motor drive is to operate based on information about the current sensor causing the current measurement gain error; and The synchronous motor drive is operated in the operating mode.

11. The method according to claim 10, in, The information includes an inaccurate estimate of the shunt resistance, the operational amplifier gain, or some combination thereof.

12. The method according to claim 10, in, The operating mode is a current operating mode.

13. The method according to claim 10, in, The operation mode is a voltage operation mode.

14. The method according to claim 8, in, Detecting whether the current measurement gain error exists based on the characteristic further includes determining that a diagnostic voltage magnitude of the output voltage signal satisfies a threshold.

15. An electronic device, include: processor; as well as a memory comprising instructions that, when executed by the processor, cause the processor to: Read the output voltage signal; Using a mathematical model of a closed-loop current control system, wherein the mathematical model includes a current measurement gain error, the current measurement gain error at least including characteristics of a pulsating voltage signal having a frequency of twice per electric revolution; performing a mathematical transformation using the mathematical model to demodulate the output voltage signal to extract characteristics of the current measurement gain error; detecting whether the current measurement gain error exists based on the characteristic; and In response to detecting the presence of the current measurement gain error, a motor phase is identified in which the current measurement gain error exists.

16. The electronic device according to claim 15, in, In response to identifying the motor phase having the current measurement gain error, the instructions further cause the processor to identify a current sensor causing the current measurement gain error based on the motor phase.

17. The electronic device of claim 16, wherein the instructions further cause the processor to: determining an operating mode in which a synchronous motor drive is to operate based on information about the current sensor causing the current measurement gain error; and The synchronous motor drive is operated in the operating mode.

18. The electronic device according to claim 17, in, The information includes an inaccurate estimate of the shunt resistance, the operational amplifier gain, or some combination thereof.

19. The electronic device according to claim 17, in, The operating mode is a current operating mode.

20. The electronic device according to claim 17, in, The operation mode is a voltage operation mode.

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