WO2020124936A1 - Fault detection method for servo dynamic brake circuit - Google Patents

Fault detection method for servo dynamic brake circuit Download PDF

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WO2020124936A1
WO2020124936A1 PCT/CN2019/086548 CN2019086548W WO2020124936A1 WO 2020124936 A1 WO2020124936 A1 WO 2020124936A1 CN 2019086548 W CN2019086548 W CN 2019086548W WO 2020124936 A1 WO2020124936 A1 WO 2020124936A1
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current
point
circuit
phase
dynamic
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PCT/CN2019/086548
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French (fr)
Chinese (zh)
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姚瑱
余国军
苗茂宇
陈富
朱洪顺
钱巍
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南京埃斯顿自动化股份有限公司
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Publication of WO2020124936A1 publication Critical patent/WO2020124936A1/en

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/34—Testing dynamo-electric machines

Definitions

  • the invention relates to a fault detection method of a servo motor dynamic braking circuit, which belongs to the field of fault detection of a servo driver.
  • the dynamic braking circuit of the motor can effectively reduce the stopping time of the motor and shorten the stopping distance. It is widely used in occasions where the motor needs to be stopped quickly, such as industrial robots. The damage of the dynamic brake circuit will cause the equipment to work abnormally, so the fault detection of the dynamic brake circuit is required.
  • the Chinese invention patent "Motor Drive Device with Dynamic Brake Circuit Fault Detection Function” discloses a dynamic brake circuit and its fault detection method, which requires a dedicated detection control output to the power transistor The signal cannot be dynamically detected and has low real-time performance.
  • the Chinese utility model patent "An AC Servo Drive System” (authorized announcement number CN203675030U) provides a simplified dynamic braking circuit, but does not give a fault detection method for the circuit.
  • the present invention proposes a detection method for the dynamic braking circuit of the motor, which does not require a special detection control signal, and realizes real-time fault detection during the dynamic braking process of the motor, which overcomes the traditional detection method Problems that require additional hardware cost and cannot be detected in real time.
  • the method for diagnosing the fault of a servo dynamic braking circuit proposed by the present invention to achieve the purpose of the invention has the following steps:
  • Servo dynamic brake circuit brake switch K, brake resistor R, diode D1, diode D2, diode D3 and voltage source inverter VSC, motor M and current sensor CT1, current sensor CT2 together form a complete dynamic system Motion circuit.
  • the current sensor CT1 is installed between the point P1 and the point U
  • the current sensor CT2 is installed between the point P2 and the point V.
  • the controller When the rotating motor needs dynamic braking, the controller will turn off the six power tubes T1-T6 of VSC and close the brake switch K.
  • the braking current will flow through two or one of the three reverse diodes of the VSC power tubes T1 to T3, through the braking switch K and braking resistor R, and then through two or one of the diodes D1 to D3. Then a three-phase winding of the motor M forms a closed loop, and the kinetic energy of the motor will be quickly consumed through the braking resistor R. Therefore, when the brake switch K is closed, if the motor speed is not lower than the set speed threshold value n th , a large braking current will be generated in one phase winding of the motor.
  • the method of the invention overcomes the problem that the traditional detection method needs additional hardware cost and cannot be detected in real time.
  • the method of the present invention only requires that the current sensor CT1 is installed between the point P1 and the point U on the hardware circuit, and the current sensor CT2 is installed between the point P2 and the point V, without additional hardware cost.
  • the method automatically completes the detection during the dynamic braking process of the motor, has good real-time performance, and does not require a special detection control signal.
  • the current sensor CT1 is installed between the point P1 and the point U on the hardware circuit, and the current sensor CT2 is installed between the point P2 and the point V. It is used for brake circuit open circuit fault detection, and the motor speed is not lower than n th to detect.
  • the three-phase current is compared with the set threshold current i th . If the three-phase current is less than the threshold current i th , it is considered that the brake circuit has an open circuit fault.
  • the threshold current i th is related to the resistance of the braking resistor R and the motor power.
  • Figure 1 is the topology of an AC motor drive system with dynamic braking and fault detection.
  • Figure 2 is a possible flow path of braking current.
  • the servo dynamic braking circuit includes: a braking switch K, a braking resistor R, a diode D1, a diode D2, and a diode D3. Together with the voltage source inverter VSC, the motor M and the current sensors CT1 and CT2, a complete dynamic braking circuit is formed. Among them, the current sensor CT1 is installed between the point P1 and the point U, and the current sensor CT2 is installed between the point P2 and the point V.
  • the controller when the rotating motor needs dynamic braking, the controller will turn off the six power tubes T1 ⁇ T6 of VSC and close the brake switch K.
  • the braking current will flow through two or one of the three reverse diodes of the VSC power tubes T1 to T3, through the braking switch K and braking resistor R, and then through two or one of the diodes D1 to D3. Then a three-phase winding of the motor M forms a closed loop, and the motor kinetic energy will be quickly consumed by the braking resistor R.
  • the brake switch K when the brake switch K is closed, if the motor speed is not lower than n th , a large braking current will be generated in one phase winding of the motor, and if the brake circuit has an open circuit fault, the braking current will not be generated .

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Stopping Of Electric Motors (AREA)

Abstract

A fault diagnosis method for a servo dynamic brake circuit. In a dynamic brake loop of the servo dynamic brake circuit, a current transducer CT1 is mounted between a point P1 and a point U, and a current transducer CT2 is mounted between a point P2 and a point V. When a brake switch K is switched off, U-phase and V-phase currents are directly obtained by means of the current transducers CT1 and CT2, a W-phase current is calculated, and the three-phase current is compared with a set threshold current ith, so as to determine whether the brake loop has an open-circuit fault. According to the fault detection method, only the mounting position of a current transducer is adjusted on hardware, and additional hardware costs do not need to be increased. The method does not require a dedicated detection control signal, and automatically completes the detection of a dynamic brake circuit during a dynamic braking process of an electric motor, and has a good real-time performance.

Description

一种伺服动态制动电路的故障检测方法A fault detection method for servo dynamic braking circuit 技术领域Technical field
本发明涉及一种伺服电机动态制动电路的故障检测方法，属于伺服驱动器故障检测领域。The invention relates to a fault detection method of a servo motor dynamic braking circuit, which belongs to the field of fault detection of a servo driver.
背景技术Background technique
电机动态制动电路可有效减小电机停止时间、缩短停车距离，广泛应用于需要电机快速停止的场合，如工业机器人等。动态制动电路的损坏会造成设备工作异常，因此需要对动态制动电路进行故障检测。The dynamic braking circuit of the motor can effectively reduce the stopping time of the motor and shorten the stopping distance. It is widely used in occasions where the motor needs to be stopped quickly, such as industrial robots. The damage of the dynamic brake circuit will cause the equipment to work abnormally, so the fault detection of the dynamic brake circuit is required.
中国发明专利《具有动态制动电路故障检测功能的电动机驱动装置》(授权公告号为CN101483402B)，公开了一种动态制动电路及其故障检测方法，该法需要向功率晶体管输出专用的检测控制信号，无法实现动态检测，实时性低。The Chinese invention patent "Motor Drive Device with Dynamic Brake Circuit Fault Detection Function" (authorized announcement number CN101483402B) discloses a dynamic brake circuit and its fault detection method, which requires a dedicated detection control output to the power transistor The signal cannot be dynamically detected and has low real-time performance.
中国实用新型专利《一种交流伺服驱动系统》(授权公告号为CN203675030U)，给出了一种简化的动态制动电路，但未给出该电路的故障检测方法。The Chinese utility model patent "An AC Servo Drive System" (authorized announcement number CN203675030U) provides a simplified dynamic braking circuit, but does not give a fault detection method for the circuit.
发明内容Summary of the invention
本发明针对现有技术存在的缺陷和不足，提出了一种电机动态制动电路的检测方法，无需专用的检测控制信号，在电机动态制动过程中实现故障的实时检测，克服了传统检测方法需要额外增加硬件成本、无法实时检测的问题。In view of the defects and deficiencies of the prior art, the present invention proposes a detection method for the dynamic braking circuit of the motor, which does not require a special detection control signal, and realizes real-time fault detection during the dynamic braking process of the motor, which overcomes the traditional detection method Problems that require additional hardware cost and cannot be detected in real time.
本发明为实现发明目的所提出的一种伺服动态制动电路的故障诊断方法，其步骤如下：The method for diagnosing the fault of a servo dynamic braking circuit proposed by the present invention to achieve the purpose of the invention has the following steps:
伺服动态制动电路：制动开关K、制动电阻R、二极管D1、二极管D2、二极管D3与电压源型逆变器VSC、电机M以及电流传感器CT1、电流传感器CT2共同构成一个完整的动态制动回路。其中电流传感器CT1安装在点P1与点U之间，电流传感器CT2安装在点P2与点V之间。Servo dynamic brake circuit: brake switch K, brake resistor R, diode D1, diode D2, diode D3 and voltage source inverter VSC, motor M and current sensor CT1, current sensor CT2 together form a complete dynamic system Motion circuit. Among them, the current sensor CT1 is installed between the point P1 and the point U, and the current sensor CT2 is installed between the point P2 and the point V.
故障检测：Fault detection:
旋转中的电机需要动态制动时，控制器将关断VSC的六个功率管T1～T6、闭合制动开关K。制动电流将流经VSC功率管T1～T3的三个反向二极管中的两个或一个，经过制动开关K、制动电阻R，再流经二极管D1～D3中的两个或一个，然后通过电机M的三相绕组形成一个闭合回路，电机动能将通过制动电阻R快速消耗。因此，当闭合制动开关K时，如果电机转速不低于设定的转速阀值n th，则将在电机某一相绕组中产生较大的制动电流，如果制动回路发生断路故障，将不能产生制动电流。通过电流传感器CT1、CT2可直接获取U相电流i u、V相电流i v，并计算得到W相电流i w＝-(i u+i v)，将三相电流与设置的阀值电流i th进行比较，如果三相电流都小于阀值电流i th，则认定制动回路发生断路故障。 When the rotating motor needs dynamic braking, the controller will turn off the six power tubes T1-T6 of VSC and close the brake switch K. The braking current will flow through two or one of the three reverse diodes of the VSC power tubes T1 to T3, through the braking switch K and braking resistor R, and then through two or one of the diodes D1 to D3. Then a three-phase winding of the motor M forms a closed loop, and the kinetic energy of the motor will be quickly consumed through the braking resistor R. Therefore, when the brake switch K is closed, if the motor speed is not lower than the set speed threshold value n th , a large braking current will be generated in one phase winding of the motor. If the brake circuit has an open circuit fault, No braking current will be generated. The U-phase current i u and V-phase current i v can be directly obtained through the current sensors CT1 and CT2, and the W-phase current i w =-(i u +i v ) is calculated, and the three-phase current and the set threshold current i th comparison, if the phase current is less than the threshold current I th, the determined brake circuit open circuit failures.
本发明方法，克服了传统检测方法需要额外增加硬件成本、无法实时检测的问题。The method of the invention overcomes the problem that the traditional detection method needs additional hardware cost and cannot be detected in real time.
本发明方法，仅需硬件电路上满足电流传感器CT1安装在点P1与点U之间，电流传感器CT2安装在点P2与点V之间，不需额外增加硬件成本。该方法在电机动态制动过程中自动完成检测，实时性好，且无需专用的检测控制信号。The method of the present invention only requires that the current sensor CT1 is installed between the point P1 and the point U on the hardware circuit, and the current sensor CT2 is installed between the point P2 and the point V, without additional hardware cost. The method automatically completes the detection during the dynamic braking process of the motor, has good real-time performance, and does not require a special detection control signal.
本发明方法，硬件电路上电流传感器CT1安装在点P1与点U之间，电流传感器CT2安装在点P2与点V之间。用于制动回路断路故障检测，电机转速不低于n th才进行检测。三相电流与设置的阀值电流i th进行比较，如果三相电流都小于阀值电流i th，则认定制动回路发生断路故障。阀值电流i th与制动电阻R的阻值、电机功率有关。 In the method of the present invention, the current sensor CT1 is installed between the point P1 and the point U on the hardware circuit, and the current sensor CT2 is installed between the point P2 and the point V. It is used for brake circuit open circuit fault detection, and the motor speed is not lower than n th to detect. The three-phase current is compared with the set threshold current i th . If the three-phase current is less than the threshold current i th , it is considered that the brake circuit has an open circuit fault. The threshold current i th is related to the resistance of the braking resistor R and the motor power.
附图说明BRIEF DESCRIPTION
图1是具有动态制动及其故障检测功能的交流电机拖动系统拓扑。Figure 1 is the topology of an AC motor drive system with dynamic braking and fault detection.
图2是制动电流的一种可能的流通路径。Figure 2 is a possible flow path of braking current.
具体实施方式detailed description
下面结合附图对本发明的实施例作详细设计步骤说明。The following describes the detailed design steps of the embodiments of the present invention with reference to the drawings.
如图1所示，该伺服动态制动电路包括：制动开关K、制动电阻R、二极管D1、二极管D2、二极管D3。与电压源型逆变器VSC、电机M以及电流传感器CT1、电流传感器CT2共同构成一个完整的动态制动回路。其中电流传感器CT1安装在点P1与点U之间，电流传感器CT2安装在点P2与点V之间。As shown in FIG. 1, the servo dynamic braking circuit includes: a braking switch K, a braking resistor R, a diode D1, a diode D2, and a diode D3. Together with the voltage source inverter VSC, the motor M and the current sensors CT1 and CT2, a complete dynamic braking circuit is formed. Among them, the current sensor CT1 is installed between the point P1 and the point U, and the current sensor CT2 is installed between the point P2 and the point V.
故障检测Fault detection
如图2所示，旋转中的电机需要动态制动时，控制器将关断VSC的六个功率管T1～T6、闭合制动开关K。制动电流将流经VSC功率管T1～T3的三个反向二极管中的两个或一个，经过制动开关K、制动电阻R，再流经二极管D1～D3中的两个或一个，然后通过电机M的三相绕组形成一个闭合回路，电机动能将通过制动电阻R快速消耗。因此，当闭合制动开关K时，如果电机转速不低于n th，则将在电机某一相绕组中产生较大的制动电流，如果制动回路发生断路故障，将不能产生制动电流。通过电流传感器CT1、CT2可直接获取U相电流i u、V相电流i v，并计算得到W相电流i w＝-(i u+i v)，将三相电流与设置的阀值电流i th进行比较，如果三相电流都小于阀值电流i th，则认定制动回路发生断路故障。 As shown in Figure 2, when the rotating motor needs dynamic braking, the controller will turn off the six power tubes T1 ~ T6 of VSC and close the brake switch K. The braking current will flow through two or one of the three reverse diodes of the VSC power tubes T1 to T3, through the braking switch K and braking resistor R, and then through two or one of the diodes D1 to D3. Then a three-phase winding of the motor M forms a closed loop, and the motor kinetic energy will be quickly consumed by the braking resistor R. Therefore, when the brake switch K is closed, if the motor speed is not lower than n th , a large braking current will be generated in one phase winding of the motor, and if the brake circuit has an open circuit fault, the braking current will not be generated . The U-phase current i u and V-phase current i v can be directly obtained through the current sensors CT1 and CT2, and the W-phase current i w =-(i u +i v ) is calculated, and the three-phase current and the set threshold current i th comparison, if the phase current is less than the threshold current I th, the determined brake circuit open circuit failures.

Claims (1)

  1. 一种伺服动态制动电路的故障诊断方法，其特征在于：A fault diagnosis method of servo dynamic braking circuit, which is characterized by:
    所述伺服动态制动电路：制动开关K、制动电阻R、二极管D1、二极管D2、二极管D3与电压源型逆变器VSC、电机M以及电流传感器CT1、电流传感器CT2共同构成一个动态制动回路；其中电流传感器CT1安装在点P1与点U之间，电流传感器CT2安装在点P2与点V之间；The servo dynamic brake circuit: the brake switch K, the brake resistor R, the diode D1, the diode D2, the diode D3 and the voltage source inverter VSC, the motor M and the current sensor CT1, the current sensor CT2 form a dynamic system Dynamic circuit; where current sensor CT1 is installed between point P1 and point U, and current sensor CT2 is installed between point P2 and point V;
    故障检测：Fault detection:
    当闭合制动开关K时，通过电流传感器CT1、CT2直接获取U相电流iu、V相电流iv，并计算得到W相电流iw＝-(iu+iv)，将三相电流与设置的阀值电流ith进行比较，如果三相电流都小于阀值电流ith，则认定制动回路发生断路故障。When the brake switch K is closed, the U-phase current iu and V-phase current iv are directly obtained through the current sensors CT1 and CT2, and the W-phase current iw=-(iu+iv) is calculated, and the three-phase current is set to the set threshold Compare the current ith, if the three-phase current is less than the threshold current ith, it is considered that the brake circuit is broken.
PCT/CN2019/086548 2018-12-17 2019-05-13 Fault detection method for servo dynamic brake circuit WO2020124936A1 (en)

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CN111478627B (en) * 2020-04-13 2021-11-05 珠海格力电器股份有限公司 Servo motor dynamic braking circuit and control method thereof
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