阅读说明：本技术 同步电动机驱动器中的电流测量增益误差的检测 (Detection of current measurement gain error in synchronous motor drive ) 是由 P·普拉莫德 V·戈文杜 K·纳姆布利 于 2020-11-27 设计创作，主要内容包括：公开了用于检测电流测量系统中的电流测量增益误差的系统和方法。方法包括：读取输出电压信号；从输出电压信号中提取电流测量增益误差的特征；基于特征检测电流测量增益误差是否存在；以及响应于检测到电流测量增益误差的存在而识别其中存在电流测量增益误差的诊断电压相位。(Systems and methods for detecting current measurement gain errors in current measurement systems are disclosed. The method comprises the following steps: reading an output voltage signal; extracting characteristics of a current measurement gain error from the output voltage signal; detecting whether a current measurement gain error exists based on the characteristics; and identifying a diagnostic voltage phase in which the current measurement gain error is present in response to detecting the presence of the current measurement gain error.)

1. A system for detecting a current measurement gain error in a current measurement system, the system comprising:

a processor; and

a memory containing instructions that, when executed by the processor, cause the processor to:

reading an output voltage signal;

extracting a characteristic of a current measurement gain error from the output voltage signal;

detecting whether the current measurement gain error is present based on the characteristic; and

in response to detecting the presence of the current measurement gain error, identifying a diagnostic voltage phase in which the current measurement gain error is present.

2. The system of claim 1, wherein in response to identifying a phase in which the current measurement gain error exists, the instructions further cause the processor to identify a current sensor causing the current measurement gain error based on the diagnostic voltage phase.

3. The system of claim 2, wherein the instructions further cause the processor to:

determining an operating mode in which the synchronous motor drive is to operate based on information about the current sensor causing the current measurement gain error; and is

Operating the synchronous motor drive in the operating mode.

4. The system of claim 3, wherein the information comprises an inaccurate estimate of shunt resistance, an operational amplifier gain, or some combination thereof.

5. The system of claim 3, wherein the operating mode is a current operating mode.

6. The system of claim 3, wherein the operating mode is a voltage operating mode.

7. The system of claim 1, wherein to detect whether the current measurement gain error is present based on the characteristic, the instructions further cause the processor to determine that a diagnostic voltage amplitude 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 comprising:

reading an output voltage signal;

extracting a characteristic of a current measurement gain error from the output voltage signal;

detecting whether the current measurement gain error is present based on the characteristic; and

in response to detecting the presence of the current measurement gain error, identifying a diagnostic voltage phase in which the current measurement gain error is present.

9. The method of claim 8, further comprising: in response to identifying the diagnostic voltage phase in which the current measurement gain error exists, identifying a current sensor causing the current measurement gain error based on the diagnostic voltage phase.

10. The method of claim 9, further comprising:

determining an operating mode in which the synchronous motor drive is to operate based on information about the current sensor causing the current measurement gain error; and is

Operating the synchronous motor drive in the operating mode.

11. The method of claim 10, wherein the information comprises an inaccurate estimate of shunt resistance, an operational amplifier gain, or some combination thereof.

12. The method of claim 10, wherein the operating mode is a current operating mode.

13. The method of claim 10, wherein the operating mode is a voltage operating mode.

14. The method of claim 8, wherein detecting whether the current measurement gain error is present based on the characteristic further comprises determining that a diagnostic voltage amplitude of the output voltage signal satisfies a threshold.

15. An electronic device, comprising:

a processor; and

a memory containing instructions that, when executed by the processor, cause the processor to:

reading an output voltage signal;

extracting a characteristic of a current measurement gain error from the output voltage signal;

detecting whether the current measurement gain error is present based on the characteristic; and

in response to detecting the presence of the current measurement gain error, identifying a diagnostic voltage phase in which the current measurement gain error is present.

16. The electronic device of claim 15, wherein in response to identifying the diagnostic voltage phase in which the current measurement gain error is present, the instructions further cause the processor to identify a current sensor causing the current measurement gain error based on the diagnostic voltage phase.

17. The electronic device of claim 16, wherein the instructions further cause the processor to:

determining an operating mode in which the synchronous motor drive is to operate based on information about the current sensor causing the current measurement gain error; and is

Operating the synchronous motor drive in the operating mode.

18. The electronic device of claim 17, wherein the information comprises an inaccurate estimate of shunt resistance, an operational amplifier gain, or some combination thereof.

19. The electronic device of claim 17, wherein the operating mode is a current operating mode.

20. The electronic device of claim 17, wherein the operating mode is a voltage operating mode.

Technical Field

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

Machines using current measurement systems may be affected by current measurement gain errors. Example causes of current measurement gain error may include inaccurate estimation of shunt resistance, operational amplifier gain, or some combination thereof. Typically, no current measurement gain error may be detected. Furthermore, there may be one or more fault current sensors that are responsible for current measurement gain errors 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.

Disclosure of Invention

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

One aspect of the disclosed embodiments includes a system for detecting 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: reading an output voltage signal; extracting characteristics of a current measurement gain error from the output voltage signal; detecting whether a current measurement gain error exists based on the characteristic; and identifying the phase for which the current measurement gain error exists in response to detecting the existence of the current measurement gain error.

Another aspect of the disclosed embodiments includes a method for detecting a current measurement gain error in a current measurement system. The method comprises the following steps: reading an output voltage signal; extracting characteristics of a current measurement gain error from the output voltage signal; detecting whether a current measurement gain error exists based on the characteristic; and identifying the phase for which the current measurement gain error exists in response to detecting the existence of the current measurement gain error.

Another aspect of the disclosed embodiments 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: reading an output voltage signal; extracting characteristics of a current measurement gain error from the output voltage signal; detecting whether a current measurement gain error exists based on the characteristic; and identifying the phase for which the current measurement gain error exists in response to detecting the existence of the current measurement gain error.

These and other aspects of the disclosure are disclosed in the following detailed description of the embodiments, the appended claims and the accompanying drawings.

Drawings

The disclosure is best understood from the following detailed description when read with the accompanying drawing figures. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.

Fig. 1 generally illustrates a current measurement gain error detection and phase identification system according to principles of the present disclosure.

Fig. 2 generally illustrates a block diagram for detecting and identifying current measurement gain errors in accordance with the principles of the present disclosure.

Fig. 3 generally illustrates a system according to the principles of the present disclosure.

Fig. 4 is a flow chart generally illustrating a method for current measurement gain error detection and phase identification in accordance with the principles of the present disclosure.

Detailed Description

The following discussion is directed to various embodiments of the disclosed subject matter. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.

Certain motion control applications (e.g., vehicles, ships, airplanes, drones, power plants, yard equipment, pumps, compressors, etc.) may include a synchronous motor drive that controls a synchronous motor that operates with closed-loop control. A current measurement system may be included in the closed loop to measure the current output by the synchronous motor. Current measurement systems may be affected by current measurement gain errors.

The current measurement gain error may refer to a difference between the measured current and the true current or the actual current. The measured current may be measured by a current measurement system, and the command current or the reference current may be input by an operator of the machine or pre-configured 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.

Typically, no current measurement gain error may be detected. Furthermore, there may be one or more fault current sensors that are responsible for current measurement gain errors 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. Such current measurement gain error(s) may result in overall system performance degradation and/or motor failure if not detected and/or corrected. Furthermore, overall system degradation may affect the life of the synchronous motor and/or the attractiveness of a customer to purchase a device that includes the synchronous motor. As a result, it is desirable to detect, identify, and mitigate current measurement gain errors.

Accordingly, systems and methods, such as those described herein, may be configured to address the above-described problems by providing techniques for detecting and identifying current measurement gain errors and taking preventative measures based on the current measurement gain errors. In some embodiments, the systems and methods described herein can detect, learn, and compensate for the effect of current measurement gain errors on the motor drive.

In some embodiments, the systems and methods described herein may be configured to provide techniques for detecting current measurement gain errors in a current measurement system used in a feedback controlled synchronous motor drive in real time. Further, the systems and methods described herein can identify a particular phase that is subject to a current measurement gain error. The systems and methods described herein can identify a particular current sensor that is malfunctioning and causing a current measurement gain error in that phase.

The systems and methods described herein may be configured to extract a feature of the current measurement gain error using various mathematical models, detect whether the current measurement gain error is present based on the feature, and identify a phase of the synchronous motor in which the current measurement gain error is present.

In some embodiments, the systems and methods described herein may be configured to take precautionary measures based on detected current measurement gain errors, phases identified as having current measurement gain errors, and/or current sensors identified as causing current measurement gain errors. The precautionary measure may include keeping the synchronous motor drive in the same operating mode as the synchronous motor is operating in, or changing to a different operating mode than the operating mode in which the synchronous motor drive is currently operating. The systems and methods described herein may be configured to use different modes of operation, such as current mode and voltage mode.

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 in-line type current measurement systems. The disclosed modeling of the current measurement sensor gain error and extraction of the characteristics of the current measurement sensor gain error enables detection of the current measurement sensor gain error and identification of the phase in which the current measurement sensor gain error exists to identify a faulty current sensor. The disclosed techniques are applicable to any motor drive with an Alternating Current (AC) motor and any current measurement architecture (both direct insertion and low side). A low-side current measurement system may refer to placing a current sensor between a low switch of a phase leg of a power converter and ground. An in-line current measurement system may refer to placing a current sensor in series with the motor phase windings such that current flowing through the motor phase also flows through the current sensor. Further, the disclosed embodiments may be implemented by a processor for real-time detection, identification and/or correction in operating a synchronous motor. The disclosed embodiments may also be implemented by a processor at the end of line (EOL) of a manufacturing facility.

Fig. 1 generally illustrates a current measurement gain error detection and phase identification system 100 (referred to herein as a "system") according to principles of the present disclosure. 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 depicted components are for illustration purposes only. Synchronous motor 116 may generate a rotational force or a linear force, such as those described herein, for powering a motion control system. Various components of the system 100 may be used as part of the 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 voltages to the synchronous motor 116 in different amounts and at different frequencies to indirectly control the speed and/or torque of the synchronous motor 116.

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 the circuit may be used. The current sensor 118 can provide a signal indicative of the current to the current estimation component 120. The current estimation component 120 may be capable of receiving a signal indicative of the current and estimating an amount of current output by the synchronous motor 116.

The current controller 102 may receive a command current (I) input by a user using a computing device or preprogrammed for the synchronous motor 116 by default. In some embodiments, the current controller 102 is used in a feedback controlled synchronous motor drive to track the command current with minimal error. The current controller 102 transmits the output voltage signal to the pulse width modulator 112. The pulse width modulator 112 may control the proportion of time when the output voltage signal is high as compared to when the output voltage signal is low for a consistent period of time. Controlling the proportion of time 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 fed to the synchronous motor 116 to control the speed of the synchronous motor 116. The synchronous motor 116 may receive the 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.

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

The current controller 102 may receive the estimated current and compare the estimated current to the command current. If there is any change, the current controller 102 may deliver an output voltage signal (V) that will cause the current to be measuredMatching the command current I. Thus, if the command current I is assumed to be constant, and the current is estimatedEqual to the command current I, then the current is estimatedIs also constant. To maintain a constant measurement current, the current controller 102 may pulse the output voltage signal, particularly in the presence of current measurement errors.

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 an isolator 110. The demodulator 106 may include a mathematical transform or mathematical operation that depends 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 the synchronous coordinate system prior to transformation, or to use an adaptive low-pass filter in a pseudo-steady-state coordinate system (adaptively) tuned according to a ripple frequency twice the synchronous frequency.

As will be described, the error detector 108 may use a mathematical model to extract characteristics of the current measurement gain error (e.g., in the event of a gain error). 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 no current measurement gain error is represented in the output voltage signal. The sinusoidal portion may refer to a pulsating portion of the output voltage signal and may be at least characteristic of a 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 characterizes the current measurement gain error.

The error detector 108 may use the mathematical transform 106 to determine whether a current measurement gain error is present based on the presence characteristic. For example, the error detector 108 may determine the amplitude of the transformed voltage signal from 106 and compare the amplitude of the output voltage signal to a threshold. If the magnitude satisfies 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 for which a current measurement gain error exists. In some embodiments, the phase isolator 110 may determine that more than one phase includes a current measurement gain error. In addition, the phase isolator 110 can use this information to identify the particular current sensor 118 that contains the current measurement gain error.

The phase isolator 110 may use a mathematical model to identify other information related to why a particular current sensor 118 caused a current measurement gain error. This information may involve the current sensor producing an inaccurate estimate of the shunt resistance, the operational amplifier gain, or some combination thereof. The error detector 108 may output a magnitude of the current measurement gain error. The phase isolator 110 may output the phase(s) and/or the particular fault current sensor 118 in the presence of current measurement gain error. The controller or circuitry included in the system 100 may take precautionary measures, such as changing or leaving the operating mode of the synchronous motor drive 130 unchanged, presenting a notification on the display of the computing device regarding the fault current sensor 118, and so forth.

The following discussion relates to mathematical models used by the systems and methods described herein. After performing the reference frame transformation applied from the static (abc) to the synchronous (dq0) frame, the system and method may utilize a model of the current measurement system. The measured motor phase current with gain error can be expressed as follows:

I_am＝(1+ΔK_ga)I_a

I_bm＝(1+ΔK_gb)I_b

I_cm＝(1+ΔK_gc)I_c

equation 1.

Wherein I_xAnd I_xmRepresenting the actual and measured currents of phase x, while Δ K_gxIndicating the gain error in the measurement. A reference coordinate system transformation (e.g., Clarke-Park transformation) may be applied to equation 1 to calculate dq0 current estimates, where the reference coordinate system transformation is expressed as follows:

h_dq0＝Th_abc

equation 2.

Where h may represent voltage, current or flux turns, and β is equal to that of a three-phase machineAnd θ is the electrical position. The inverse Clarke-Park transform is represented as follows:

h_abc＝T_ih_dq0

equation 3.

The Clarke-Park transformation in equation 2 is applied to the measured motor phase current with gain error represented in equation 1 below to calculate the dq0 current estimate, which is represented as follows:

equation 4.

ΔI_gd＝ΔK_gsI_d+ΔK_gp(cos(2θ+φ_gp)I_d+sin(2θ+φ_gp)I_d)

Equation 5.

ΔI_gq＝ΔK_gsI_q+ΔK_gp(sin(2θ+φ_gp)I_d-cos(2θ+φ_gp)I_q)

Equation 6.

Equation 7.

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

AC component with DC component having unique current measurement gain error characteristics

Equation 8.

The mathematical model represented in equation 8 represents the sensing subsystem and represents what the current measured when the closed loop current control of the synchronous motor is not active. 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 the reference current, which may be expressed as follows:

equation 9.

Wherein ω is_dAnd ω_qIs the closed loop bandwidth parameter setting of the current controller. When the bandwidth is sufficiently high, the actual current value may be approximated as follows:

equation 10.

WhereinAndis the current command value.

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

equation 11.

By demodulating the dq voltage waveform, a pulsating component (sinusoidal component) Δ V 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 motoring revolution, as follows:

equation 12.

In some embodiments, for non-salient machines, i.e. L_d＝L_qThe DC part of the transformed voltage signal is represented as follows:

equation 13.

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

equation 14.

WhereinAnd is

Using a mathematical model comprising the equations described herein, a current measurement gain error can be detected by comparing the DC signal to an appropriate predefined threshold.

Fig. 2 generally illustrates a block diagram 200 for detecting and identifying current measurement gain errors in accordance with the principles of the present disclosure. The block diagram 200 includes a block 202 for demodulation, a block for a current measurement gain error detector 204, and a faulted 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 demodulator 106, error detector 108, and phase isolator 110, respectively.

The demodulation block 202 may receive the final synchronous frame voltage (e.g., output voltage signal) from the current controller 102. In performing filtering to extract the diagnostic voltage V_uAnd V_uThe demodulation block 202 may then apply equation 12 to the final synchronous coordinate system voltage. The magnitude and phase calculation block 208 may calculate a diagnostic voltage magnitude V_mIt contains information that there is a current measurement gain error, as described in equation 14. The gain error detector block 210 may compare the diagnostic voltage amplitude to a predetermined threshold to check if the threshold is exceeded. The motor speed can also be used using equation 14Resistance (RC)And an inductorEstimated value of (d) and current command value amplitudeTo perform the comparison. 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 satisfies the threshold, then the gainThe error detector block 210 may output a current measurement gain error indicator U_cmIndicating that there is a current measurement gain error in one or more motor phases.

The faulted phase identifier block 206 may receive the diagnostic voltage phase signal from the amplitude and phase calculation block 208 and use the diagnostic voltage phase signal to identify the particular motor phase P for which there is a current measurement gain error_cm(e.g., A, B or C in a three-phase synchronous motor). The fault phase identifier block 206 may identify the particular current sensor 118 that contains the current measurement gain error based on the diagnostic voltage phase. Upon detection of a current measurement gain error by gain error detector 210, fault phase identifier block 206 utilizes diagnostic voltage phase phi along with current angle command value alpha^*And a resistorAnd an inductorBy identifying the gain error phase of the signal P as described in equation 14_cmSet to A, B, C or M to determine if a single motor phase (in phase A, B, C) contains gain error or if multiple phases have gain error at the same time, where M indicates the gain error in multiple phases at the same time. In the case of a single phase imbalance, the faulted phase identifier block 206 identifies a particular phase. The gain error phase identification logic is as follows:

whereinIs indicative of phi_gpIs determined by the estimated value of (c),and phi_wIs a phase angle tolerance window for gain error phase identification. Note that when the imbalances are respectively atWhile in phase A, B, C, the diagnostic voltage phase becomes equal to 0, φ₀、-φ₀. This may be determined by setting the value of the gain error in any single phase to a non-zero value and setting the other offsets to zero. For example, if Δ K in equation 5 is due to gain error in phase B_gbIs nonzero and Δ K_gaAnd Δ K_gcZero, then the resulting phase angle phi_gpBecomes phi₀. Similar calculations can be performed for the other phases using equation 5.

Fig. 3 generally illustrates a controller system 300 according to the principles of the present disclosure. The controller system 300 includes a current measurement gain error controller 104 communicatively coupled to a memory 302. The current measurement gain error detector 104 may include a processor. The processor may comprise 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 perform at least the techniques disclosed herein. In particular, the computer instructions, when executed by the current measurement gain error detector 104, may cause the current measurement gain error detector 104 to perform the operations of the method 400, as further described below with reference to fig. 4. The controller system 300 may be communicatively coupled to a computing device 304. The computing device 304 may include a processor, 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.

Fig. 4 is a flow chart generally illustrating a method 400 for current measurement gain error and phase identification in accordance with 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, method 400 extracts a characteristic 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 contains only a constant portion, there may be no current measurement gain error because the sinusoidal portion of the output voltage signal represents a ripple that includes the characteristics of the current measurement gain error. Thus, 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 result from the current controller 102 maintaining a measured current and/or an estimated current containing a current measurement gain error equal to the commanded current.

At 406, the method 400 detects whether a current measurement gain error is present from the output voltage signal. That is, if the current measurement gain error is characterized, the method 400 determines a diagnostic voltage magnitude and compares the magnitude to a threshold. In some embodiments, method 400 may use equation 14 when comparing to a threshold. If the diagnostic voltage amplitude satisfies the threshold, then the method 400 detects that a current measurement gain error exists. If the diagnostic voltage amplitude does not satisfy the threshold, then the method 400 does not detect the presence of a current measurement gain error.

At 408, in response to detecting the presence of the current measurement gain error, the method 400 identifies a diagnostic voltage phase in which the current measurement gain error is present. Method 400 may use equation 14 to determine a diagnostic voltage phase and then use the diagnostic voltage phase to identify the particular current sensor that is faulty. Accordingly, the method 400 may identify the current sensor 118 that contains the current measurement gain error based on the diagnostic voltage phase. For example, each different current sensor 118 may measure each different phase. The method 400 may determine the operating mode in which the synchronous motor drive is to operate based on information about the current sensor 118 that caused the current measurement gain error. Using one or more of the equations above, the method 400 may provide information regarding the occurrence of current sensor faults for both the low-side current measurement system and the in-line current measurement system.

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, the 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, the method 400 may select to change the mode of operation to a different mode of operation (e.g., voltage mode or current mode) than the mode of operation in which the motor drive is currently operating. In some embodiments, the method 400 may present a notification on a computing device used by a user indicating that the identified current sensor 118 is faulty and instruct an operator to check, repair, and/or replace the faulty current sensor 118.

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 the output voltage signal, extract a characteristic of the current measurement gain error from the output voltage signal, detect whether the current measurement gain error is present based on the characteristic, and identify a phase in which the current measurement gain error is present in response to detecting the presence of the current measurement gain error.

In some embodiments, in response to identifying a phase for which a current measurement gain error exists, the instructions further cause the processor to identify a current sensor causing 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 the information about why the current sensor caused 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, the 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 than the operating mode in which the motor drive is currently operating. In some embodiments, to detect whether a current measurement gain error is present based on the characteristic, the instructions further cause the processor to determine that the amplitude of the output voltage signal satisfies a threshold.

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

In some embodiments, in response to identifying a phase for which a current measurement gain error exists, the method further comprises identifying a current sensor causing the current measurement gain error based on the phase. In some embodiments, the method further comprises determining an operating mode in which the synchronous motor drive is to operate based on information about why the current sensor caused the current measurement gain error, causing the synchronous motor drive to operate in the operating mode. In some embodiments, the information includes an inaccurate estimate of the shunt resistance, the 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 than the operating mode in which the motor drive is currently operating.

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 the output voltage signal, extract a characteristic of the current measurement gain error from the output voltage signal, detect whether the current measurement gain error is present based on the characteristic, and identify a phase in which the current measurement gain error is present in response to detecting the presence of the current measurement gain error.

In some embodiments, in response to identifying a phase for which a current measurement gain error exists, the instructions further cause the processor to identify a current sensor causing 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 the information about why the current sensor caused 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, the 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 than the operating mode in which the motor drive is currently operating.

The above discussion is meant to be illustrative of the principles and various embodiments of the present invention. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications.

The term "example" is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word "example" is intended to present concepts in a concrete fashion. The term "or" as used in this application is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless specified otherwise or clear from context, "X comprises a or B" is intended to mean any of the natural inclusive permutations. That is, if X comprises A; x comprises B; or X includes both A and B, then "X includes A or B" is satisfied under any of the above circumstances. In addition, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form. Furthermore, unless so described, the use of the term "one embodiment" or "an embodiment" throughout is not intended to refer to the same embodiment or implementation.

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 circuitry. In the claims, the term "processor" should be understood to include any of the foregoing hardware, either alone or in combination. The terms "signal" and "data" are used interchangeably.

As used herein, the term module may include a packaged functional hardware unit designed for use with other components, a set of instructions executable by a controller (e.g., a processor executing software or firmware), a processing circuit configured to perform a specific function, and a separate hardware or software component that interfaces with a larger system. For example, a module may include, or be a combination of, 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. In other embodiments, a module may include a memory that stores instructions executable by a controller to implement features of the module.

Further, in one aspect, for example, the systems described herein may be implemented using a general purpose computer or a general purpose processor with a computer program that, when executed, implements any of the respective methods, algorithms, and/or instructions described herein. Additionally or alternatively, for example, a special purpose computer/processor may be utilized which may contain other hardware for carrying out any of the methods, algorithms, or instructions described herein.

Furthermore, all or portions of embodiments of the present disclosure may take the form of a computer program product accessible from, for example, a computer usable or computer readable medium. A computer-usable or computer-readable medium may be any apparatus that can, for example, tangibly embody, store, communicate, or transport the program for use by or in connection with any processor. The medium may be, for example, an electronic, magnetic, optical, electromagnetic or semiconductor device. Other suitable media are also available.

The above-described embodiments, embodiments and aspects have been described in order to allow easy understanding of the present invention, and do not limit the present invention. On the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest meaning so as to encompass all such modifications and equivalent arrangements as is permitted under the law.