Magnetic encoder compensation system and compensation method thereof

Abstract

A magnetic encoder compensation system includes a permanent magnet motor module, a load motor module, a torque meter, a power meter, and a control module. The control module controls the permanent magnet motor of the permanent magnet motor module to operate in a high-speed range and controls the load motor of the load motor module to dynamically load the permanent magnet motor with maximum torque, thereby detecting torque and voltage information via the torque meter and power meter. The control module determines whether to perform zero-point compensation for the magnetic encoder based on the torque and voltage information, calculates the compensation angle based on the zero-point angle, and burns the magnetic encoder of the permanent magnet motor module based on the compensation angle. The present invention also relates to a magnetic encoder compensation method.

Description

Technical Field

[0001] The present invention relates to a magnetic encoder compensation system and a compensation method thereof, and more particularly to a magnetic encoder compensation system and a compensation method thereof for performing zero point angle fine adjustment and burning correction through dynamic loading. Background Art

[0002] like Figure 1 As shown, a conventional magnetic encoder compensation system 100a includes a permanent magnet motor module 200, a load motor module 1, and a control module 4. The permanent magnet motor module 200 internally includes a permanent magnet motor 202 and a magnetic encoder 204, while the load motor module 1 includes a load motor 12 and a high-precision encoder 18. Because the permanent magnet motor module 200 must meet predetermined specifications before shipment, the angle of the magnetic encoder 204 must be calibrated before shipment. However, conventional techniques often utilize the load motor 12 of the load motor module 1 to drive the permanent magnet motor 202 of the permanent magnet motor module 200 via a coupling 12A. After comparing the signals between the high-precision encoder 18 in the load motor module 1 and the magnetic encoder 204 of the permanent magnet motor 202 under test, the angle of the magnetic encoder 204 is then calibrated and compensated. However, this method only corrects the angle of the magnetic encoder 204 alone. When assembled into a motor drive system, various errors can still lead to insufficient overall output performance. Furthermore, using a high-precision encoder 18 will also increase the construction cost of the magnetic encoder compensation system 100 a.

[0003] Specifically, the concentricity of the magnetic encoder 204 relative to the rotating shaft varies after assembly, leading to signal delays and errors even with the same controller model. Consequently, even with the same process conditions and the same motor controller driving the same batch of permanent magnet motors, slight performance differences can still occur between individual permanent magnet motors.

[0004] Due to these shortcomings, even with identical materials and the same manufacturing process, the output performance of each permanent magnet motor module 200 may not be completely consistent. Some may even fall below specification and fail to meet performance standards, requiring rework or even scrapping of the permanent magnet motor module 200. However, most of these issues are simply due to offset in the position signal from the magnetic encoder 204.

[0005] Therefore, how to collect data under dynamic loading to fine-tune the magnetic encoder angle and burn in corrections to ensure the consistency of permanent magnet motor module performance, thereby reducing rework and labor costs and unnecessary scrap losses, is a major research topic that the inventors of the present disclosure intend to conduct. Summary of the Invention

[0006] To address the aforementioned issues, the present invention provides a magnetic encoder compensation system to overcome the problems of the prior art. Therefore, the magnetic encoder compensation system of the present invention includes a permanent magnet motor module, a load motor module, a torque meter, an wattmeter, and a control module. The permanent magnet motor module includes a permanent magnet motor, a permanent magnet motor driver, and a magnetic encoder, and the load motor module includes a load motor and a load motor driver. The wattmeter is coupled to the permanent magnet motor driver, the torque meter is coupled to the permanent magnet motor, the load motor, and the wattmeter, and the control module is coupled to the permanent magnet motor module, the load motor module, and the wattmeter. The control module controls the permanent magnet motor to operate in a high speed range between the rated speed and the maximum speed through the permanent magnet motor driver, and controls the load motor to operate to dynamically load the permanent magnet motor with maximum torque through the load motor driver. At the same time, the torque meter detects torque information corresponding to the permanent magnet motor in the high speed range, and the wattmeter detects voltage information corresponding to the permanent magnet motor driver in the high speed range through the permanent magnet motor driver. The control module determines whether the permanent magnet motor performance meets the standard by comparing the torque information with the torque standard and the voltage information with the voltage standard. If either the torque information or the voltage information does not meet the standard, the control module reads the zero point angle of the magnetic encoder, calculates the compensation angle corresponding to the zero point angle based on the zero point compensation control, and burns the magnetic encoder according to the compensation angle.

[0007] To solve the above-mentioned problems, the present invention provides a magnetic encoder compensation method to overcome the problems of the prior art. Therefore, the magnetic encoder compensation method of the present invention includes: (a) controlling the permanent magnet motor to operate in a high speed range between the rated speed and the maximum speed. (b) controlling the load motor to operate so as to dynamically load the permanent magnet motor with maximum torque, and simultaneously obtaining torque information corresponding to the permanent magnet motor in the high speed range, and obtaining voltage information corresponding to the permanent magnet motor driver driving the permanent magnet motor in the high speed range. (c) disabling the permanent magnet motor driver. (d) comparing the torque information with the torque standard, and comparing the voltage information with the voltage standard. (e) determining whether the permanent magnet motor performance meets the standard based on the comparison results of step (d), including: (e1) if the torque information meets the torque standard and the voltage information meets the voltage standard, determining that the permanent magnet motor performance meets the standard and is accepted as a good product. (e2) if the torque information does not meet the torque standard and the voltage information also does not meet the voltage standard, determining that the permanent magnet motor performance does not meet the standard and is rejected as a defective product. (e3) If either the torque information or the voltage information does not meet the standard, it is determined that the magnetic encoder assembled with the permanent magnet motor requires zero point compensation. The zero point angle of the magnetic encoder is read, and a compensation angle corresponding to the zero point angle is calculated based on the zero point compensation control. The magnetic encoder is then programmed with the compensation angle. (f) Steps (a) to (e3) are repeated to confirm whether the permanent magnet motor performance meets the standard.

[0008] The main purpose and technical effect of the present invention is to correct the dynamic error through the maximum torque dynamic loading performance test in the high speed range, slightly correct the compensation amount of the zero point angle of the magnetic encoder and burn it into the magnetic encoder, thereby achieving the technical effect of ensuring that the performance of the permanent magnet motor is fully exerted and consistent with the mass production performance.

[0009] To further understand the techniques, means, and technical effects employed by the present invention to achieve its intended objectives, please refer to the following detailed description of the present invention and the accompanying drawings. It is believed that an in-depth and detailed understanding of the objectives, features, and characteristics of the present invention can be obtained thereby. However, the accompanying drawings are provided for reference and illustration only and are not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a circuit block diagram of an existing magnetic encoder compensation system;

[0011] Figure 2 FIG4 is a circuit block diagram of a magnetic encoder compensation system for calibrating a magnetic encoder according to the present invention;

[0012] Figure 3A This is a vector diagram of the first embodiment of the basic principle of magnetic encoding compensation of the present invention;

[0013] Figure 3B This is a vector diagram of the second embodiment of the basic principle of magnetic encoding compensation of the present invention;

[0014] Figure 3C This is a vector diagram of the third embodiment of the basic principle of magnetic encoding compensation of the present invention;

[0015] Figure 4 Schematic diagram of the torque-to-weight curve of the present invention;

[0016] Figure 5 Flowchart of the magnetic encoder compensation method of the present invention;

[0017] Figure 6 Detailed implementation diagram of the magnetic encoder compensation method of the present invention;

[0018] Figure 7A A torque analysis diagram of the magnetic encoder compensation method of the present invention under test verification; and

[0019] Figure 7B This is a voltage analysis diagram under the test verification of the magnetic encoder compensation method of the present invention.

[0020] Description of reference numerals:

[0021] 100a, 100b…Magnetic encoder compensation system

[0022] 1... Load motor module

[0023] 12…Load motor

[0024] 14…Load motor driver

[0025] 16…Load motor encoder

[0026] 18…High-precision encoder

[0027] 12A, 12B…coupling

[0028] 2…Torque meter

[0029] 3…Electricity meter

[0030] 4…Control module

[0031] 42…Controller

[0032] 44…Writing device

[0033] 46…Switch

[0034] 200...Permanent magnet motor module

[0035] 202…Permanent magnet motor

[0036] 204…Magnetic encoder

[0037] 206…Permanent magnet motor driver

[0038] Pd…Drive power supply

[0039] Ss…Detection signal

[0040] Sc…control signal

[0041] T info ...torque information

[0042] V info ...voltage information

[0043] Spd cmd ...speed command

[0044] Spd MAX ...maximum speed

[0045] Spd rated …rated speed

[0046] T cmd ...torque command

[0047] T real ...actual torque

[0048] T target ...torque threshold

[0049] T coefficient...torque coefficient

[0050] V real ...actual voltage

[0051] V Limit …voltage threshold

[0052] Aw(ZeroOffset write )…Magnetic angle after compensation

[0053] Az(ZeroOffset read )…zero point angle

[0054] Ac(ZeroOffset compensate )…Compensation angle

[0055] Pa…angle parameter

[0056] E…back electromotive force

[0057] I…current

[0058] θ…angle

[0059] Z…Impedance

[0060] Steps (S100) to (S600)

[0061] Curves…Test1~Test3 DETAILED DESCRIPTION

[0062] The technical content and detailed description of the present invention are described as follows with reference to the accompanying drawings:

[0063] See also Figure 2 This is a circuit block diagram of the magnetic encoder compensation system for correcting the magnetic encoder of the present invention, and is also referred to in conjunction with Figure 1The magnetic encoder compensation system 100b includes a permanent magnet motor module 200, a load motor module 1, a torque meter 2, an electric power meter 3, and a control module 4. The magnetic encoder compensation system 100b is used to perform pre-factory calibration and testing on the permanent magnet motor module 200 before it leaves the factory to ensure that the permanent magnet motor module 200 meets the performance specifications before it is accepted. Otherwise, the magnetic encoder 204 needs to be burned to fine-tune the angle of the magnetic encoder 204 so that the performance of the permanent magnet motor 202 meets the standard. If the performance of the permanent magnet motor 202 still fails to meet the standard after several consecutive adjustments, the permanent magnet motor 202 must be rejected. The permanent magnet motor module 200 includes a permanent magnet motor 202, a magnetic encoder 204, and a permanent magnet motor driver 206. The permanent magnet motor driver 206 couples the permanent magnet motor 202 and the magnetic encoder 204. The magnetic encoder 204 and the permanent magnet motor 202 are assembled together. Permanent magnet motor driver 206 drives permanent magnet motor 202 via power supply Pd, and magnetic encoder 204 detects the position of the rotor of permanent magnet motor 202 and provides a detection signal Ss. Permanent magnet motor module 200 primarily utilizes magnetic field weakening technology to control permanent magnet motor 202, enabling it to achieve optimal performance at high speeds.

[0064] The load motor module 1 includes a load motor 12, a load motor driver 14, and a load motor encoder 16. The load motor driver 14 couples the load motor 12 and the load motor encoder 16. The load motor driver 14 controls and adjusts the drive power Pd (i.e., voltage and current) of the load motor 12 based on a detection signal Ss. The load motor 12 is coupled to the permanent magnet motor 202 to dynamically load the permanent magnet motor 202 with maximum torque. A more practical method is to mechanically couple the load motor 12 to the permanent magnet motor 202 via a coupling 12B. This allows for pre-calibration and testing of the maximum torque dynamic loading of the permanent magnet motor 202 via the coupling 12B.

[0065] The torque meter 2 is coupled to the permanent magnet motor 202, the load motor 12 and the power meter 3, and is used to detect the torque of the permanent magnet motor 202 and provide the actual torque T real The power meter 3 is coupled to the permanent magnet motor driver 206 and is used to detect the voltage on the permanent magnet motor driver 206 for driving the permanent magnet motor 202 and provide an actual voltage V real And the voltage information V is obtained by calculation info , and the actual torque T real Calculated as torque information T infoThe control module 4 is coupled to the permanent magnet motor module 200, the load motor module 1, and the power meter 3, and performs pre-calibration and testing of the permanent magnet motor module 200 by controlling the permanent magnet motor module 200 and the load motor module 1. Specifically, the control module 4 controls the operation of the permanent magnet motor 202 by controlling the permanent magnet motor driver 206, and controls the operation of the load motor 12 by controlling the load motor driver 14. When the permanent magnet motor 202 and the load motor 12 are operating, the control module 4 receives torque information T info With voltage information V info The operating conditions of the permanent magnet motor 202 and the permanent magnet motor driver 206 are known to determine whether the permanent magnet motor module 200 is a good product.

[0066] Furthermore, during assembly of the permanent magnet motor module 200, a DC correction method is typically used to pre-compensate the zero point of the magnetic encoder 204 to correct for static errors in the permanent magnet motor module 200. However, even after static error correction, the permanent magnet motor module 200 may still experience a reference position signal offset due to component dimensional tolerances, material property variations, and assembly variability. This reference position signal offset is typically caused by a delay in signal transmission, representing a dynamic error in the permanent magnet motor module 200. In a permanent magnet motor module 200 controlled using magnetic field weakening technology, this dynamic error can significantly impact the performance of the permanent magnet motor 202 due to the effects of current control, especially at high speeds, where position feedback accuracy is extremely demanding. At higher speeds or deeper magnetic field weakening conditions, the dynamic error is significantly amplified, causing position feedback from the magnetic encoder 204 to be inaccurate. Therefore, the main purpose and technical effect of the present invention is to correct the dynamic error through a high-speed maximum torque dynamic loading performance test (for example, but not limited to, above 3000 rpm), so as to slightly correct the zero point angle Az of the magnetic encoder 204, thereby achieving the technical effect of ensuring that the performance of the permanent magnet motor 202 is fully exerted and consistent with the mass production performance.

[0067] See also Figure 1 The control module 4 controls the permanent magnet motor driver 206 via the control signal Sc to control the permanent magnet motor 202 to operate at the maximum speed. In practice, the signal error can be effectively obtained and dynamic error compensation can be performed even when the operation is fast enough. Therefore, the control module 4 can control the permanent magnet motor 202 to operate in the high speed range between the rated speed and the maximum speed. The control module 4 also controls the load motor driver 14 via the control signal Sc to control the load motor 12, so that the load motor 12 dynamically loads the permanent magnet motor 202 with the maximum torque through the coupling 12B. Then, the torque meter 2 detects the actual torque T of the permanent magnet motor 202 operating in the high speed range. realThe power meter 3 detects the actual voltage V output by the permanent magnet motor driver 206 when the permanent magnet motor 202 is running in the high speed range. real The voltage information V is provided by calculation info , and the actual torque T real Calculated as torque information T info Specifically, the torque meter 2 is disposed between the coupling 12B and the permanent magnet motor 202 and is electrically connected to the dynamometer 3. The torque meter 2 detects the actual torque T of the permanent magnet motor 202. real The actual torque T is provided to the power meter 3. real Calculated as torque information T info , and the power meter 3 sends the torque information T info With voltage information V info Provided to the control module 4.

[0068] The control module 4 receives the torque information T info With voltage information V info , and according to the torque information T info Determine the corresponding actual torque T real Whether the torque standard is met, and according to the voltage information V info Determine the corresponding actual voltage V real Whether the voltage standard is reached. That is, the control module 4 is based on the torque information T info With voltage information V info Determine whether the performance of the permanent magnet motor 202 meets the torque standard and voltage standard respectively to determine whether to adjust (fine-tune) the zero angle Az of the magnetic encoder 204. Specifically, the torque standard is the predetermined torque specification of the permanent magnet motor 202 according to the design, and the torque information T info If the torque is greater than or equal to the predetermined torque standard, it represents the actual torque T real The voltage standard is the predetermined voltage specification of the permanent magnet motor driver 206 according to the design, and the voltage information V info Less than or equal to the predetermined voltage standard represents the actual voltage V real The magnetic encoder compensation system 100b of the present invention is mainly used to adjust and confirm the torque information T info Meet the torque standard and confirm the voltage information V info The voltage standard is achieved to obtain an angle parameter Pa that meets the torque standard and the voltage standard, wherein the angle parameter Pa includes a compensated magnetic encoding angle Aw required for writing into the magnetic encoder 204 .

[0069] When the control module 4 is based on the torque information T info Determine the actual torque T realReach the torque standard, and according to the voltage information V info Determine the actual voltage V real When the voltage reaches the standard, the control module 4 determines that the performance of the permanent magnet motor 202 of the permanent magnet motor module 200 meets the standard, and thus determines that the permanent magnet motor module 200 is acceptable (ie, the calibration and testing of the magnetic encoder 204 are completed and the pre-shipment test is passed).

[0070] When the control module 4 is based on the torque information T info Determine the actual torque T real The torque standard is not met, or according to the voltage information V info Determine the actual voltage V real When the voltage standard is not reached, if any of the above conditions occurs, it is necessary to calculate the angle parameter Pa to be compensated and adjusted, wherein the angle parameter Pa includes a compensated magnetic encoder angle Aw required to be written into the magnetic encoder 204. Then, the calculated angle parameter Pa is written into the magnetic encoder 204, for example, by burning, to adjust the angle of the magnetic encoder 204 and compensate the performance of the permanent magnet motor 202. Further, the control module 4 includes a controller 42 and a writing device 44. The controller 42 is coupled to the permanent magnet motor module 200, the load motor module 1, the torque meter 2 and the power meter 3, and is used to read the zero point angle Az from the magnetic encoder 204 and the torque information T provided by the power meter 3. info The angle parameter Pa is calculated based on the torque standard. The writing device 44 (such as but not limited to a device with a writing function such as a burner) is coupled to the controller 42 and the magnetic encoder 204, and is used to write the angle parameter Pa to the magnetic encoder 204 to adjust (i.e., fine-tune) the zero angle Az of the magnetic encoder 204 to perform zero compensation. The angle parameter Pa is calculated mainly by detecting the permanent magnet motor module 200 and reading the zero angle Az of the magnetic encoder 204, and the control module 4 adjusts the angle parameter Pa based on the actual torque T. real The torque error from the torque threshold (ie, torque standard) generates a compensation angle Ac, and the sum of the zero angle Az and the compensation angle Ac is calculated as the angle parameter Pa, which is then written into the magnetic encoder 204. In one embodiment, the power meter 3 is coupled to the controller 42 of the control module 4.

[0071] However, in some cases, the permanent magnet motor module 200 may contain defects during assembly, resulting in the permanent magnet motor 202 of the permanent magnet motor module 200 failing to meet performance standards regardless of calibration. Therefore, the control module 4 can pre-set a predetermined number of times to repeat the calibration of the magnetic encoder 204. After repeatedly writing different angle parameters Pa to the magnetic encoder 204 a predetermined number of times, if the performance of the permanent magnet motor 202 of the permanent magnet motor module 200 still fails to meet performance standards, the control module 4 will determine that the permanent magnet motor module 200 is defective (NG) and reject it.

[0072] The control module 4 may optionally further include a switch 46. The switch 46 is coupled between the writing device 44 and the magnetic encoder 204, and when the writing device 44 intends to write the angle parameter Pa into the magnetic encoder 204, the controller 42 controls the switch 46 to be turned on so that the angle parameter Pa can be written into the magnetic encoder 204. When it is not necessary to write the angle parameter Pa into the magnetic encoder 204, the controller 42 controls the switch 46 to be turned off so that the path between the writing device 44 and the magnetic encoder 204 is disconnected. It is worth mentioning that the test platform of the magnetic encoder compensation system 100b of the present invention can simultaneously perform the calibration of the magnetic encoder 204 and the actual torque T of the permanent magnet motor 202. real The actual voltage V of the permanent magnet motor driver 206 real Therefore, only a single platform is needed to complete the testing and calibration of the permanent magnet motor module 200. Figure 1 The conventional magnetic encoder compensation system 100a can only calibrate the magnetic encoder 204, and the voltage and torque test of the permanent magnet motor module 200 needs to be tested again using another platform. Figure 1 Compared with the prior art, the magnetic encoder compensation system 100b of the present invention can achieve the technical effect of saving testing and calibration operation time.

[0073] See also Figures 3A to 3C This is a vector diagram of the basic principle of magnetic encoding compensation of the present invention (first to third embodiments), and is also referred to in conjunction with Figure 2 .exist Figures 3A to 3C In the figure, the vertical axis is the q axis, the horizontal axis is the d axis, and the vectors of the back electromotive force E and the current I of the permanent magnet motor module 200 are respectively as follows: Figures 3A to 3C shown. Figure 3A Assume that the magnetic encoder provides the best origin reference of 70 degrees, and Figures 3B to 3C They are the magnetic encoders after the angle shift respectively. Figure 3AIn the figure, the angle θ between the back electromotive force E and the current I (i.e., the compensation magnetic encoder angle Aw after burning the magnetic encoder 204) is 70 degrees. Since voltage V = E + Z * I (where Z is impedance), the magnitude of the voltage V vector will change with the magnitude of the angle θ when the magnitude of the impedance Z vector remains unchanged. Figure 3B and Figure 3C In the example, it is assumed that the angle θ shifts from 70 degrees to 80 degrees and 60 degrees respectively. Figure 3B As shown in FIG, when the origin reference provided by the magnetic encoder shifts from 70 degrees to 80 degrees, the angle θ between the current I and the back electromotive force E will change. This will cause the required voltage V to decrease, and the maximum speed of the permanent magnet motor 202 to increase. On the contrary, if Figure 3C As shown, when the origin reference provided by the magnetic encoder shifts from 70 degrees to 60 degrees, the required voltage V will increase, causing the maximum speed of the permanent magnet motor 202 to decrease.

[0074] See also Figure 4 This is a curve diagram of the torque ratio of the present invention, please refer to Figures 2-3C The output torque performance of the permanent magnet motor 202 is significantly correlated with the angle θ between the back electromotive force E and the current I, as shown in the following mathematical formula:

[0075] T e =λ E ×I q →T e =λ E ×I×cosθ…(1)

[0076]

[0077] Where T e is the electromagnetic torque, and T r is the reluctance torque, and its total torque T t like Figure 4 It can be clearly seen that when the reference position of the magnetic encoder 204 is offset, the angle θ will change, causing the output torque performance of the permanent magnet motor 202 to vary. Therefore, the actual torque T real The size of the total torque T t size) and the actual voltage V real However, in practice, when the permanent magnet motor 202 is running in the high speed range, the actual voltage V real The voltage specification of the permanent magnet motor module 200 (such as but not limited to the voltage specification of the internal components) cannot be exceeded. If the voltage specification is exceeded, there is a risk of loss of control. Therefore, the control module 4 is in the actual torque T real Reach the torque standard, and the actual voltage Vreal If the voltage standard is also met, the actual voltage V can be lowered by adjusting (fine-tuning) the angle parameter Pa. real (The actual torque T real Thus, the voltage margin of the permanent magnet motor module 200 can be improved. On the other hand, when the control module 4 determines the actual torque T real The torque threshold is not reached, and the actual voltage V real If the voltage threshold is not reached, the permanent magnet motor module 200 can be directly determined to be a defective (NG) product and rejected.

[0078] See also Figure 5 This is a flow chart of the motor operation method of the magnetic encoder compensation method of the present invention, and is also referred to in conjunction with Figures 2-4 . The magnetic encoder compensation method is used to calibrate the magnetic encoder 204 of the permanent magnet motor module 200, and the magnetic encoder compensation method includes, after the permanent magnet motor 202 and the magnetic encoder 204 are assembled, performing a relatively large angle zero point correction (S100) on the magnetic encoder 204. When the permanent magnet motor module 200 is assembled, a DC correction method is usually used to first calibrate the zero point position of the magnetic encoder 204 to correct the static error of the permanent magnet motor module 200. Among them, this step is not a necessary step, and it all depends on the actual requirements when assembling the permanent magnet motor module 200. Then, the permanent magnet motor 202 is docked with the load motor 12. The preferred implementation method is that the load motor 12 is mechanically docked with the permanent magnet motor 202 through the coupling 12B, so as to perform pre-calibration and testing operations of maximum torque dynamic loading by docking the permanent magnet motor 202 through the coupling 12B, which will be described in detail later.

[0079] Then, the permanent magnet motor 202 is controlled to run at the rated speed Spd rated To maximum speed Spd MAX A preferred implementation is that the control module 4 controls the permanent magnet motor 202 to operate at the rated speed Spd by controlling the permanent magnet motor driver 206. rated To maximum speed Spd MAX The high speed range between 100 and 100 makes the permanent magnet motor 202 run fast enough to effectively obtain the signal error and perform dynamic error compensation. Then, the control module 4 controls the load motor driver 14 to control the load motor 14 to dynamically load the permanent magnet motor 202 with the maximum torque. At the same time, when the permanent magnet motor 202 stably runs at a specific speed in the high speed range, the torque information T corresponding to the permanent magnet motor 202 in the high speed range is obtained. info, and when the permanent magnet motor 202 is running in the high speed range, the voltage information V corresponding to the permanent magnet motor driver 206 info (S140). The preferred implementation method is that the control module 4 controls the load motor 12 by controlling the load motor driver 14, so as to dynamically load the permanent magnet motor 202 with the maximum torque through the coupling 12B. Then, the torque meter 2 detects the actual torque T of the permanent magnet motor 202 when it is running in the high speed range. real The actual torque T is provided to the power meter 3. real Calculated as torque information T info The power meter 3 detects the actual voltage V output by the permanent magnet motor driver 206 when the permanent magnet motor 202 is running in the high speed range. real The voltage information V is provided after calculation info Finally, the power meter 3 converts the torque information T info And voltage information V info Provided to controller 42.

[0080] Then, the permanent magnet motor driver 206 is disabled (S160). In a preferred embodiment, power to the permanent magnet motor driver 206 is stopped or control of the permanent magnet motor driver 206 by the control signal Sc is stopped, and the permanent magnet motor driver 206 is confirmed to be powered off, and the permanent magnet motor 202 and the magnetic encoder 204 are confirmed to be stopped. Preferably, the load motor 12 should also be controlled to stop for accurate detection. The purpose of disabling the permanent magnet motor driver 206 is to enable the control module 4 to accurately calculate the angle parameter Pa and write it to the encoder 204, for example, by burning it, thereby correcting the angle of the magnetic encoder 204 and compensating for the performance of the permanent magnet motor 202. The angle parameter Pa includes a compensated magnetic encoder angle Aw required for writing to the magnetic encoder 204.

[0081] Next, according to the torque information T info Compare with the torque standard and according to the voltage information V info The voltage is compared with the voltage standard to determine whether the performance of the permanent magnet motor 202 meets the standard (S200). In a preferred embodiment, when the permanent magnet motor 202 and the load motor 12 are running, the control module 4 receives the actual torque T provided by the torque meter 2 through the power meter 3. real And the calculated torque information T info , and the power meter 3 takes the actual voltage V eral The calculated voltage information V info , according to the torque information T info Determine the corresponding actual torque T real Whether the torque standard is met, and according to the voltage information V info Determine the corresponding actual voltage Vreal Specifically, the torque standard is the predetermined torque specification of the permanent magnet motor 202 according to the design, and the torque information T info If the torque is greater than or equal to the predetermined torque standard, it represents the actual torque T real The voltage standard is that the permanent magnet motor driver 206 is designed according to the predetermined voltage specification, and the voltage information V info Less than or equal to the predetermined voltage standard represents the actual voltage V real is less than or equal to a predetermined voltage threshold.

[0082] Then, if the torque information T info Reach the torque standard, and the voltage information V info When the voltage standard is reached, the performance of the permanent magnet motor 202 is determined to be up to standard and the permanent magnet motor 202 and the magnetic encoder 204 assembled therewith are determined to be good products and accepted (S220). info Determine the actual torque T real Reach the torque standard, and according to the voltage information V info Determine the actual voltage V real When the voltage standard is reached, the control module 4 determines that the motor performance of the permanent magnet motor module 200 has reached the standard, and thus the permanent magnet motor module 200 is determined to be good and acceptable (i.e., the calibration and testing of the magnetic encoder 204 have been completed and the pre-shipment test has been passed). In step (S220), the actual torque T real Reach the torque standard, and the actual voltage V real When the voltage standard is met, the actual torque T is reduced by adjusting the angle parameter Pa. real The actual voltage V real In practice, when the permanent magnet motor 202 is running in a high speed range, the actual voltage V real It is low, so it is not easy to exceed the voltage specification of the permanent magnet motor module 200 (for example, but not limited to, the voltage specification of the internal components), which can avoid the risk of loss of control. real Reach the torque standard, and the actual voltage V real If the voltage standard is also met, the actual voltage V is lowered by adjusting (fine-tuning) the angle parameter Pa. real (Actual torque T real It is reduced accordingly), but it still needs to meet the torque standard and voltage standard. In this way, the technical effect of improving the voltage margin of the permanent magnet motor module 200 specification can be achieved, wherein the angle parameter Pa includes a compensated magnetic encoder angle Aw required for writing the magnetic encoder 204.

[0083] Then, if the torque information T info The torque standard is not met, and at the same time the voltage information V info If the voltage standard is not met, the permanent magnet motor 202 is judged to be unqualified and the permanent magnet motor 202 and the magnetic encoder 204 are judged to be defective and rejected (S240). info Determine the actual torque T real The torque threshold is not reached, and at the same time according to the voltage information V info Determine the actual voltage V real If the voltage threshold is not reached, the permanent magnet motor module 200 can be directly determined to be a defective (NG) product and rejected.

[0084] Then, if the torque information T info With voltage information V info When one of the two does not meet the standard, it is determined that the magnetic encoder 204 needs to be compensated for zero point. The control module 4 reads a zero point angle Az of the magnetic encoder 204 and combines it with the torque information T info The compensation angle Ac of the corresponding magnetic encoder 204 is calculated based on the zero point compensation control and the torque standard, and the magnetic encoder 204 is burned according to the compensation angle Ac to achieve zero point compensation of the magnetic encoder 204 (S260). In a preferred embodiment, the control module 4 includes a controller 42 and a writing device 44. The controller 42 calculates the compensation angle Ac of the corresponding magnetic encoder 204 based on the zero point angle Az and the torque information T info The controller 42 calculates the compensation angle Ac based on the zero-point angle Az and the compensation angle Ac, and sends the angle parameter Pa to the writing device 44. The writing device 44 writes the angle parameter Pa to the magnetic encoder 204 by burning or other means to adjust (i.e., fine-tune) the zero-point angle Az of the magnetic encoder 204 to perform zero-point compensation. The angle parameter Pa is preferably calculated by detecting the permanent magnet motor module 200 and reading the zero-point angle Az of the magnetic encoder 204. The control module 4 calculates the angle parameter Pa based on the actual torque T real The torque error calculated from the torque threshold (i.e., the torque standard) generates a compensation angle Ac. The zero-point angle Az and the compensation angle Ac are summed to calculate an angle parameter Pa, where the angle parameter Pa includes a compensated magnetic encoder angle Aw required for writing into the magnetic encoder 204. It should be noted that the compensation angle Ac calculated based on the zero-point compensation in step (S260) is smaller than the adjustment angle based on the zero-point calibration in step (S100). The former is intended to compensate for the performance of the permanent magnet motor 202, while the latter is intended to return the basic angle of the magnetic encoder 204 to zero.

[0085] Then, steps (S120) to (S260) are repeated to fine-tune the angle of the magnetic encoder 204 and confirm whether the performance of the permanent magnet motor 202 meets the standard (S280). In the loop of repeating steps (S120) to (S260) multiple times, if the performance of the permanent magnet motor 202 meets the standard after adjustment, the process ends at step (S220). On the contrary, if the torque information T info With voltage information V info If any of the above parameters still does not meet the standard after the previous adjustment, step (S260) is repeated to reprogram the magnetic encoder 204 to recalibrate the zero angle Az. Finally, after repeating the adjustments from steps (S120) to (S260) a predetermined number of times, if the performance of the permanent magnet motor 202 still does not meet the standard, the permanent magnet motor 202 is determined to be defective and rejected (S300). It should be noted that in some cases, the permanent magnet motor module 200 may have defects during manufacturing or assembly, resulting in the permanent magnet motor module 200 failing to meet the performance standard regardless of any adjustment. Therefore, the control module 4 can pre-set a predetermined number of repeated adjustments to the magnetic encoder 204. If the performance of the permanent magnet motor 202 in the permanent magnet motor module 200 still fails to meet the standard after the control module 4 programs the magnetic encoder 204 for zero point compensation a predetermined number of times, the permanent magnet motor 202 is determined to be defective (NG) and rejected.

[0086] See also Figure 6 The details of the magnetic encoder compensation method of the present invention are shown in FIG. 2 to FIG. 5 , and refer to FIG. Figure 5 In step (S400), the magnetic encoder compensation system 100b performs a maximum torque dynamic loading test. Figure 5 The control module 4 controls the permanent magnet motor driver 206 to provide a speed command Spd cmd The permanent magnet motor 202 is driven to the rated speed Spd rated To maximum speed Spd MAX and performs maximum torque dynamic loading when the permanent magnet motor 202 stably operates at a specific speed in the high speed range, and at the same time enables the permanent magnet motor driver 206 to provide a torque command T cmd Control the torque output of the permanent magnet motor 202 to 100%. In step (S420), the Figure 5 Step (S200) to determine the actual torque T real Is it greater than or equal to the predetermined torque threshold T? target , actual voltage V real Is it less than or equal to the predetermined voltage threshold V LimitIn step (S440), the performance of the permanent magnet motor 202 is determined to be good and acceptable. In step (S460), the actual torque T real The actual voltage V real Since the actual torque T real The actual voltage V real One of them does not meet the standard, so the correction steps of steps (S500) to (S560) are continued.

[0087] In step (S500), the controller 42 receives the actual torque T provided by the torque meter 2 through the power meter 3. real , and the actual torque T real Calculated as torque information T info The torque information T provided by the power meter 3 to the controller 42 info , voltage information V info , and the zero angle ZeroOffset provided by the magnetic encoder 204 read (Az) to prepare for the subsequent calculation of the angle parameter Pa. In step (S520), the controller 42 calculates the compensation angle of the magnetic encoder 204 to be compensated, which can be expressed as: ZeroOffset compensate (Ac)=(T real -T target )T coefficient Among them, T coefficient is the torque coefficient, and the torque coefficient T coefficient It can be obtained through simulation analysis of the controller 42. In step (S540), the controller 42 calculates the compensated magnetic encoder angle Aw to be written into the magnetic encoder 204, which can be expressed as: ZeroOffset write (Aw)=ZeroOffset read (Az)-ZeroOffset compensate .

[0088] In step (S560), the control module 4 adjusts the compensation angle ZeroOffset compensateThe calculation is then performed, and the corresponding angle parameter Pa is written into the magnetic encoder 204 via the writing device 44 to adjust (i.e., fine-tune) the angle of the magnetic encoder 204 and compensate for the performance of the permanent magnet motor 202. After step (S560) is completed, the process proceeds to step (S580) to determine whether the angle parameter Pa has been written into the magnetic encoder 204 a predetermined number of times. If so, the permanent magnet motor module 200 is determined to be defective (NG) and rejected (S600). If not, the process returns to step (S400), where the angle parameter Pa includes a compensated magnetic encoder angle Aw required for writing into the magnetic encoder 204.

[0089] See also Figure 7A This is a torque analysis diagram under the test verification of the magnetic encoder compensation method of the present invention, Figure 7B This is the voltage analysis diagram under the test verification of the magnetic encoder compensation method of the present invention, please refer to Figures 2 to 6 , and refer back to Figure 7A 、 7B .exist Figure 7A In the experimental test of the permanent magnet motor 202 in the high speed range (9000rpm), the torque output specification that meets the specification must be >6Nm. It is necessary to confirm that if the torque meets the standard in the high speed range, it can be ensured that the performance can still meet the standard when the permanent magnet motor 202 speed is lower than 9000rpm. Figure 7B In the specification, it is defined that the voltage output specification that meets the specification must be <35V to ensure that the permanent magnet motor driver 206 does not cause system loss of control due to excessive voltage when running at various speeds.

[0090] exist Figure 7A and 7B For example, curve Test1 shows the test results when the permanent magnet motor 202 is running at 9000 rpm. Because the voltage meets the performance specification, but the torque does not meet the performance specification (e.g., torque: 5.58 Nm, voltage: 31.28 V), the zero-point angle Az must be adjusted through zero-point compensation to correct the performance of the permanent magnet motor module 200. Curve Test2 shows the test results when the torque meets the performance specification, but the voltage exceeds the performance specification (torque: 6.5 Nm, voltage: 35.1 V). Therefore, the zero-point angle Az must be adjusted through zero-point compensation to correct the performance of the permanent magnet motor module 200. Curve Test3 shows the test results after zero-point compensation and zero-point angle Az adjustment. Both torque and voltage meet the performance specifications (torque: 6.3 Nm, voltage: 34.217 V), which proves that the compensation mechanism of the present invention can effectively improve the performance of the permanent magnet motor module 200.

[0091] According to the magnetic encoder compensation system and magnetic encoder compensation method proposed in the present invention, dynamic error correction is performed through the maximum torque dynamic loading performance test in the high speed range, so as to slightly correct the compensation amount of the zero point angle of the magnetic encoder and burn it into the magnetic encoder, thereby achieving the technical effect of ensuring that the performance of the permanent magnet motor is fully exerted and consistent with the mass production performance.

[0092] However, the above description is only a detailed description and drawings of the preferred specific embodiments of the present invention, and the features of the present invention are not limited thereto and are not intended to limit the present invention. The full scope of the present invention should be based on the claims. All embodiments that are consistent with the concepts of the claims of the present invention and similar variations thereof should be included in the scope of the present invention. Any changes or modifications that can be easily thought of by any person skilled in the art within the field of the present invention can be covered by the claims of this disclosure.

Claims

1. A magnetic encoder compensation system, comprising: A permanent magnet motor module, comprising a permanent magnet motor, a permanent magnet motor driver and a magnetic encoder; a load motor module, comprising a load motor and a load motor driver; an electric power meter coupled to the permanent magnet motor driver; a torque meter coupled to the permanent magnet motor, the load motor, and the power meter; and a control module coupled to the permanent magnet motor module, the load motor module and the power meter; The control module controls the permanent magnet motor to operate in a high speed range between the rated speed and the maximum speed through the permanent magnet motor driver, and controls the load motor to operate to dynamically load the permanent magnet motor with a maximum torque through the load motor driver. The control module also detects torque information corresponding to the permanent magnet motor in the high speed range through the torque meter, and detects voltage information corresponding to the permanent magnet motor driver in the high speed range through the power meter. The control module determines whether the permanent magnet motor performance meets the standard by comparing the torque information with a torque standard and the voltage information with a voltage standard. If either the torque information or the voltage information does not meet the standard, the control module reads a zero point angle of the magnetic encoder, calculates a compensation angle corresponding to the zero point angle based on zero point compensation control, and burns the magnetic encoder according to the compensation angle.

2. The magnetic encoder compensation system of claim 1 , wherein the torque meter detects an actual torque of the permanent magnet motor when operating in the high speed range and calculates and provides the torque information; the power meter detects an actual voltage of the permanent magnet motor driver when the permanent magnet motor operates in the high speed range and calculates and provides the voltage information; and the control module determines whether the torque information meets the torque standard based on whether the actual torque is greater than or equal to a torque threshold, and determines whether the voltage information meets the voltage standard based on whether the actual voltage is less than or equal to a voltage threshold.

3. The magnetic encoder compensation system of claim 2 , wherein when the performance of the permanent magnet motor does not meet the standard, the control module calculates the compensation angle based on a torque error between the actual torque and the torque threshold, and burns the sum of the zero angle and the compensation angle into an angle parameter of the magnetic encoder. 4 . The magnetic encoder compensation system as claimed in claim 1 , wherein the load motor and the permanent magnet motor are connected via a coupling, the torque meter is disposed between the coupling and the permanent magnet motor, and the torque meter is electrically connected to the dynamometer.

5. The magnetic encoder compensation system of claim 1 , wherein the control module comprises: a controller coupled to the permanent magnet motor module, the load motor module, and the power meter, for calculating the compensation angle according to the zero-point angle, the torque information, and the torque standard; and A writing device is coupled to the controller and the magnetic encoder, and is used for programming the magnetic encoder according to the compensation angle.

6. A magnetic encoder compensation method, comprising: (a) controlling a permanent magnet motor to operate in a high speed range between a rated speed and a maximum speed; (b) controlling a load motor to dynamically load the permanent magnet motor with a maximum torque, and simultaneously obtaining torque information corresponding to the permanent magnet motor in the high speed range, and obtaining voltage information corresponding to a permanent magnet motor driver driving the permanent magnet motor in the high speed range; (c) disabling the permanent magnet motor drive; (d) comparing the torque information with a torque standard, and comparing the voltage information with a voltage standard; (e) determining whether the performance of the permanent magnet motor meets the standard based on the comparison result of step (d), including: (e1) If the torque information meets the torque standard and the voltage information meets the voltage standard, the permanent magnet motor is judged to meet the performance standard and is accepted as a good product; (e2) if the torque information does not meet the torque standard and the voltage information also does not meet the voltage standard, the permanent magnet motor is determined to be substandard and is rejected as a defective product; and (e3) if either the torque information or the voltage information does not meet the requirements, determining that a magnetic encoder assembled with the permanent magnet motor requires zero point compensation, by reading a zero point angle of the magnetic encoder, calculating a compensation angle corresponding to the zero point angle based on zero point compensation control, and programming the magnetic encoder according to the compensation angle; and (f) Repeat steps (a) to (e3) to confirm whether the performance of the permanent magnet motor meets the requirements.

7. The magnetic encoder compensation method according to claim 6, further comprising, before step (a): Perform zero point calibration on the magnetic encoder.

8. The magnetic encoder compensation method of claim 6, wherein step (d) comprises: (d1) detecting an actual torque of the permanent magnet motor in the high speed range and calculating and providing the torque information, and determining whether the torque information meets the torque standard based on whether the actual torque is greater than or equal to a torque threshold; and (d2) detecting an actual voltage output by the permanent magnet motor driver when the permanent magnet motor is operating in the high speed range, calculating and providing the voltage information, and determining whether the voltage information meets the voltage standard based on whether the actual voltage is less than or equal to a voltage threshold.

9. The magnetic encoder compensation method according to claim 8, wherein step (e1) further comprises: The actual torque and the actual voltage are reduced by adjusting an angle parameter, wherein the angle parameter is calculated based on the sum of the zero angle and the compensation angle.

10. The magnetic encoder compensation method according to claim 8, wherein step (e3) comprises: (e31) reading the zero angle of the magnetic encoder by detecting the permanent magnet motor module; (e32) calculating the compensation angle according to a torque error between the actual torque and the torque threshold; and (e33) Calculating an angle parameter burned into the magnetic encoder based on the sum of the zero point angle and the compensation angle.

11. The magnetic encoder compensation method according to claim 6, further comprising: (g) After step (e3) is repeated a predetermined number of times and the performance of the permanent magnet motor still does not meet the standard, the permanent magnet motor is determined to be a defective product and is rejected.

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