CN-121978523-A - Motor stall detection system and method

Abstract

The invention discloses a motor stall detection system and a motor stall detection method, which relate to the technical field of motor control, wherein the system comprises a preset register set, a detection unit and a control unit, wherein the preset register set is used for storing a preset number of continuous electric half cycles; wherein the preset number of consecutive electrical half-cycles comprises the latest electrical half-cycle; the calculation circuit is connected with the preset register set and is used for calculating to obtain an electrical period detection value according to all electrical half periods in the preset register set; the invention can utilize the electric period detection to compare the counter potential between the rising current quadrant and the falling current quadrant, thereby rapidly and conveniently detecting the stall state of the motor, reducing the detection cost and the operation complexity, and adopting the digital circuit to realize the detection of the stall of the motor, and has small occupied area and low cost.

Inventors

• Shao Jiajin
• ZHAO ZHENG

Assignees

• 杭州瑞盟科技股份有限公司

Dates

Publication Date

20260505

Application Date

20260324

Claims (10)

1. 1. A motor stall detection system, comprising: the device comprises a preset register set, a first storage unit, a second storage unit and a third storage unit, wherein the preset register set is used for storing a preset number of continuous electrical half-cycles, and the preset number of continuous electrical half-cycles comprise the latest electrical half-cycle; the calculation circuit is connected with the preset register set and is used for calculating to obtain an electrical period detection value according to all electrical half periods in the preset register set; And the stall fault judging circuit is connected with the calculating circuit and is used for determining that the running condition of the motor to be detected is a motor stall state when the electric cycle detection value is greater than or equal to a stall threshold value.
2. 2. The motor stall detection system of claim 1, wherein the computing circuit comprises: and the average value calculation unit is connected with the preset register set and is used for calculating the average value of all the electric half cycles in the preset register set and storing the average value as an electric cycle detection value into the electric cycle detection register.
3. 3. The motor stall detection system of claim 1, wherein the set of preset registers is in particular a shift register set for storing the latest of the preset number of electrical half cycles.
4. 4. A motor stall detection system as claimed in claim 3, wherein the shift register bank comprises 4 register banks for storing the latest 4 consecutive electrical half cycles.
5. 5. The motor stall detection system of any of claims 1 to 4, further comprising: And the stall threshold re-detection circuit is connected with the preset register set and is used for calculating the stall threshold according to the electric cycle detection value of the motor to be detected in steady-speed operation and the electric cycle detection value in stall operation.
6. 6. The motor stall detection system of claim 5, further comprising: and the re-detection judging circuit is connected with the preset register set and the stall threshold re-detection circuit and is used for triggering the stall threshold re-detection circuit to start the detection calibration process of the stall threshold when detecting that the change of the electric half period reaches a threshold re-detection condition.
7. 7. The motor stall detection system of claim 6, wherein the re-detection determination circuit comprises: The device comprises a first counter, a first counter and a second counter, wherein the first counter is used for adding 1 to the count value of the first counter when the absolute value of the difference between the current electric half period and the last electric half period is smaller than a change threshold value, and subtracting 1 to the count value of the first counter when the absolute value of the difference between the current electric half period and the last electric half period is not larger than the change threshold value, wherein the current electric half period is the latest electric half period, and the last electric half period is the last electric half period of the current electric half period; And the first comparison unit is connected with the first counter and the stall threshold re-detection circuit and is used for determining that the change of the electric half period reaches the threshold re-detection condition when the count value of the first counter reaches a first count threshold, triggering the stall threshold re-detection circuit to start the stall threshold detection and calibration process and resetting the count value of the first counter.
8. 8. The motor stall detection system of claim 7, wherein the stall threshold re-detection circuit comprises: The second counter is used for increasing the count value of the second counter by 1 if the absolute value of the difference between the current electric half period and the last electric half period is smaller than a first stable threshold value when the motor normally operates, and decreasing the count value of the second counter by 1 if the absolute value of the difference between the current electric half period and the last electric half period is not smaller than the first stable threshold value; The second comparison unit is connected with the second counter and is used for outputting a stable speed record signal to the stable speed result register group when the count value of the second counter reaches a second count threshold value; the speed stabilizing result register set is connected with the second comparison unit and the calculation circuit and is used for storing the current electrical period detection value output by the calculation circuit as the electrical period detection value of the motor to be detected in the speed stabilizing operation according to the speed stabilizing record signal; The third comparison unit is connected with the second counter and the calculation circuit and is used for outputting a stall counting signal to the second counter if the current electrical cycle detection value output by the calculation circuit is smaller than a stall confirmation threshold after controlling the motor to be detected to stall; the second comparison unit is also used for outputting a stall record signal to a stall result register group when the count value of the second counter reaches a third count threshold value; the stall result register set is connected with the second comparison unit and the calculation circuit and is used for storing the current electrical cycle detection value output by the calculation circuit as the electrical cycle detection value of the motor to be detected in steady-speed operation according to the stall record signal; the stall threshold calculation unit is connected with the speed stabilizing result register set and the stall result register set and is used for calculating the average value of the electric cycle detection value of the motor to be detected in the speed stabilizing operation and the electric cycle detection value in the stall operation to obtain the stall threshold; The second counter is further configured to increment a count value of the second counter by 1 if an absolute value of a difference between a current electrical half cycle and a previous electrical half cycle is smaller than a second stable threshold value after the motor to be detected resumes normal operation, decrement the count value of the second counter by 1 if the absolute value of the difference between the current electrical half cycle and the previous electrical half cycle is not smaller than the second stable threshold value, and determine that the stall threshold detection calibration process is completed when the count value of the second counter reaches a fourth count threshold value.
9. 9. The motor stall detection system of claim 8, further comprising: The electric half-period difference value comparison circuit is connected with the first counter, the second counter and the preset register set and is used for calculating the absolute value of the difference between the current electric half period and the last electric half period, outputting the comparison result of the absolute value and the change threshold value to the first counter, and outputting the comparison result of the absolute value and the first stability threshold value or the second stability threshold value to the second counter.
10. 10. A method of detecting motor stall, comprising: Acquiring an electrical half-period of a motor to be detected; Determining an electrical cycle detection value according to a preset number of continuous electrical half cycles, wherein the preset number of continuous electrical half cycles comprises the latest electrical half cycle, and the preset number is a positive integer greater than or equal to 2; And when the electrical cycle detection value is greater than or equal to a stall threshold, determining that the running condition of the motor to be detected is a motor stall state.

Description

Motor stall detection system and method Technical Field The invention relates to the technical field of motor control, in particular to a motor stall detection system and a motor stall detection method. Background Currently, it is known that motor current, counter potential and torque load have a relationship in which the counter potential is 90 ° out of phase with the motor current when empty (i.e., torque load is 0), and is smaller from the phase difference as the torque load increases gradually, and is almost in phase with the motor current when full (maximum load). Therefore, in the related art, whether the motor stalls is detected by detecting the phase shift of the counter potential and the motor current. However, detecting the counter potential requires an external analog circuit, is relatively area-consuming, is costly, and requires relatively high detection requirements. Therefore, how to detect the motor stall rapidly and conveniently, and reduce the cost and the operation complexity is an urgent problem to be solved nowadays. Disclosure of Invention The invention aims to provide a motor stall detection system and a motor stall detection method, so that motor stall can be detected rapidly and conveniently, and cost and operation complexity are reduced. In order to solve the technical problem, the present invention provides a motor stall detection system, which is characterized by comprising: the device comprises a preset register set, a first storage unit, a second storage unit and a third storage unit, wherein the preset register set is used for storing a preset number of continuous electrical half-cycles, and the preset number of continuous electrical half-cycles comprise the latest electrical half-cycle; the calculation circuit is connected with the preset register set and is used for calculating to obtain an electrical period detection value according to all electrical half periods in the preset register set; And the stall fault judging circuit is connected with the calculating circuit and is used for determining that the running condition of the motor to be detected is a motor stall state when the electric cycle detection value is greater than or equal to a stall threshold value. In another aspect, the computing circuit includes: and the average value calculation unit is connected with the preset register set and is used for calculating the average value of all the electric half cycles in the preset register set and storing the average value as an electric cycle detection value into the electric cycle detection register. In another aspect, the preset register set is specifically a shift register set, for storing the latest preset number of electrical half cycles. In another aspect, the shift register set includes 4 register sets for storing the latest 4 consecutive electrical half cycles. In another aspect, the system further comprises: And the stall threshold re-detection circuit is connected with the preset register set and is used for calculating the stall threshold according to the electric cycle detection value of the motor to be detected in steady-speed operation and the electric cycle detection value in stall operation. In another aspect, the system further comprises: and the re-detection judging circuit is connected with the preset register set and the stall threshold re-detection circuit and is used for triggering the stall threshold re-detection circuit to start the detection calibration process of the stall threshold when detecting that the change of the electric half period reaches a threshold re-detection condition. In another aspect, the re-detection judging circuit includes: The device comprises a first counter, a first counter and a second counter, wherein the first counter is used for adding 1 to the count value of the first counter when the absolute value of the difference between the current electric half period and the last electric half period is smaller than a change threshold value, and subtracting 1 to the count value of the first counter when the absolute value of the difference between the current electric half period and the last electric half period is not larger than the change threshold value, wherein the current electric half period is the latest electric half period, and the last electric half period is the last electric half period of the current electric half period; And the first comparison unit is connected with the first counter and the stall threshold re-detection circuit and is used for determining that the change of the electric half period reaches the threshold re-detection condition when the count value of the first counter reaches a first count threshold, triggering the stall threshold re-detection circuit to start the stall threshold detection and calibration process and resetting the count value of the first counter. In another aspect, the stall threshold re-detection circuit comprises: The second counter is used for increasing the count value of t