CN111157869A - Motor controller IGBT (insulated Gate Bipolar transistor) open circuit and motor three-phase open circuit detection method - Google Patents

Abstract

The invention discloses a motor controller IGBT (insulated gate bipolar translator) open circuit and motor three-phase open circuit detection method, wherein two IGBTs capable of forming a closed loop with a motor are conducted according to a specific sequence, the rest IGBTs are turned off, the absolute value of current is recorded, and the open circuit fault of the IGBT and the three-phase open circuit fault of the motor are analyzed and judged through six groups of three-phase current data; according to the method for detecting the IGBT breaking and the three-phase breaking of the motor controller, the IGBT breaking fault and the three-phase breaking fault of the motor can be identified through a program without disassembling the motor controller and the motor, so that the method is suitable for carrying out initialization diagnosis and maintenance diagnosis on the faults, and is convenient and rapid; the circuit breaking faults at multiple positions can be detected by one-time detection, and the detection efficiency is high and accurate.

Description

Motor controller IGBT (insulated Gate Bipolar transistor) open circuit and motor three-phase open circuit detection method

Technical Field

The invention relates to the technical field of automobile accessory processing equipment, in particular to a method for detecting IGBT (insulated gate bipolar transistor) open circuit and motor three-phase open circuit of a motor controller.

Background

The motor controller comprises IGBTs (UH, UL, VH, VL, WH and WL), a control circuit, current sensors (A1, A2 and A3) and a bus capacitor (C), wherein the current sensors sample three-phase currents, the control circuit calculates and controls the switching states of the IGBTs, the on and off of the IGBTs realize the current control of the three phases of the motor U, V, W, and if the IGBTs are disconnected or the three phases of the motor are disconnected, a circular running magnetic field cannot be formed to generate faults.

When the motor breaks down, the motor is required to stop working, disassembly and detection are carried out, whether the motor stator breaks is judged through external measurement of three-phase resistance, the detection procedure is troublesome, and the working progress is delayed.

Disclosure of Invention

The technical problem to be solved by the invention is to overcome the existing defects and provide a method for detecting the IGBT open circuit and the motor three-phase open circuit of the motor controller.

In order to achieve the purpose, the invention provides the following technical scheme: a method for detecting IGBT open circuit and motor three-phase open circuit of a motor controller comprises the steps of conducting two IGBTs capable of forming a closed loop with a motor and turning off the rest IGBTs according to a specific sequence, recording an absolute value of current, and analyzing and judging an IGBT open circuit fault and a motor three-phase open circuit fault through six groups of three-phase current data.

Further, by turning on two of the IGBTs capable of forming a closed loop with the motor and turning off the remaining IGBTs in a specific order, the absolute value of the current is recorded, comprising the steps of:

s1, conducting UH and VL for a fixed time t1, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, wherein the absolute values are expressed as IU1, IV1 and IW 1;

s2, turning on VH and WL for a fixed time t2, simultaneously turning off other 4 IGBTs, reading and recording the absolute values of currents in A1, A2 and A3, and expressing the absolute values as IU2, IV2 and IW 2;

s3, turning on WH and UL for a fixed time t3, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, wherein the absolute values are expressed as IU3, IV3 and IW 3;

s4, turning on VH and UL for a fixed time t4, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, and expressing the absolute values as IU4, IV4 and IW 4;

s5, turning on WH and VL for a fixed time t5, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, wherein the absolute values are expressed as IU5, IV5 and IW 5;

and S6, conducting UH and WL for a fixed time t6, simultaneously turning off other 4 IGBTs, reading and recording the absolute values of currents in A1, A2 and A3, and expressing the absolute values as IU6, IV6 and IW 6.

Further, after the data is acquired, the fault judgment condition includes:

p1, if IU1< Ithr, IU6< Ithr, and IU3 ≧ Ithr, or IU4 ≧ Ithr, determining UH open circuit;

p2, if IV2< Ithr, and IV4< Ithr, and (IV1 ≧ Ithr, or IV5 ≧ Ithr), determining VH open circuit;

p3, if IW3< Ithr, IW5< Ithr, and (IW2 ≧ Ithr, or IW6 ≧ Ithr), determining WH open circuit;

p4, if IU3< Ithr, IU4< Ithr, and (IU1 ≧ Ithr, or IU6 ≧ Ithr), determining UL open circuit;

p5, if IV1< Ithr, and IV5< Ithr, and (IV2 ≧ Ithr, or IV4 ≧ Ithr), then VL is considered open-circuited;

p6, if IW2< Ithr, and IW6< Ithr, and (IW3 ≧ Ithr, or IW5 ≧ Ithr), deeming WL open circuit;

p7, if IU1< Ithr, and IU6< Ithr, and IU3< Ithr, and IU4< Ithr, then U phase is deemed open;

p8, if IV2< Ithr, and IV4< Ithr, and IV1< Ithr, and IV5< Ithr, then V phase open is deemed;

p9, if IW3< Ithr, and IW5< Ithr, and IW2< Ithr, and IW6< Ithr, then W phase is deemed open;

wherein Ithr is the current threshold.

Further, when the conduction time t1, t2, t3, t4, t5 and t6 are determined, the conduction current is ensured to be larger than the current threshold Ithr under the condition that the IGBT and the motor have no fault.

Further, t1, t2, t3, t4, t5 and t6 have the same value.

And further, after the fault is judged, more than two times of detection are carried out, and the result is compared for inspection.

Furthermore, the correctness is automatically detected and verified through a disconnection detection system.

Further, the disconnection detection system includes:

a data acquisition module: the detection device is electrically connected with the motor and used for collecting six groups of three-phase currents of the motor during detection;

an analysis and judgment module: the data acquisition module is connected, the data acquisition module analyzes the acquired three-phase current, judges whether the IGBT is broken or not and whether the three phases of the motor are broken or not according to the breaking judgment condition, and outputs a breaking signal when the judgment result is breaking;

an output display module: the connection analysis and judgment module is used for transmitting the circuit breaking signal to a controller of the motor and displaying the circuit breaking signal through a display device;

an alarm module: and the connection analysis and judgment module is used for alarming when the circuit is broken.

Compared with the prior art, the invention has the beneficial effects that: the IGBT open circuit and motor three-phase open circuit detection method of the motor controller has the following advantages:

1. by switching on and off the IGBTs in the motor controller according to a specific sequence, the IGBT open-circuit fault and the motor three-phase open-circuit fault can be identified, and the detection process is simple and quick.

2. The IGBT open circuit fault and the motor three-phase open circuit fault can be identified through a program without disassembling the motor controller and the motor, and the method is suitable for carrying out initialization diagnosis and maintenance diagnosis on the fault, and is convenient and fast.

3. The circuit breaking faults at multiple positions can be detected by one-time detection, and the detection efficiency is high and accurate.

Drawings

FIG. 1 is a flow chart of the IGBT break and the three-phase break detection of the motor controller in the invention;

fig. 2 is a schematic structural diagram of a motor controller and a permanent magnet synchronous motor according to the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-2, the present invention provides the following technical solutions:

as shown in fig. 2, the motor controller is composed of IGBTs (UH, UL, VH, VL, WH, WL), a control circuit, current sensors (a1, a2, A3), and a bus capacitor (C), wherein the current sensors sample three-phase currents, the control circuit calculates and controls the switching states of the IGBTs, and the three-phase current control of the motor U, V, W is realized by turning on and off the IGBTs.

Example one

As shown in figure 1, the IGBT open circuit of the motor controller and the three-phase open circuit detection method of the motor are characterized in that two IGBTs capable of forming a closed loop with the motor are conducted according to a specific sequence, the rest IGBTs are turned off, the absolute value of current is recorded, and the open circuit fault of the IGBT and the three-phase open circuit fault of the motor are analyzed and judged through six groups of three-phase current data.

The method comprises the following steps of firstly, recording the absolute value of current by switching on two IGBTs which can form a closed loop with a motor and switching off the rest IGBTs according to a specific sequence, wherein the current absolute value is recorded by switching on two IGBTs which can form a closed loop with the motor according to a specific sequence, and the method comprises the following steps:

s1, conducting the UH and the VL for a fixed time t1, and simultaneously turning off other 4 IGBTs, wherein the UH, the U phase of the motor, the V phase of the motor and the VL form a closed loop, current is generated in the loop, and absolute values of the current in A1, A2 and A3 are read and recorded and are expressed as IU1, IV1 and IW 1;

s2, conducting the VH and the WL for a fixed time t2, and simultaneously turning off other 4 IGBTs, wherein the VH, the motor V phase, the motor W phase and the WL form a closed loop, current is generated in the loop, and absolute values of the current in A1, A2 and A3 are read and recorded and are expressed as IU2, IV2 and IW 2;

s3, conducting the WH and the UL for a fixed time t3, and simultaneously turning off other 4 IGBTs, wherein the WH, the W phase of the motor, the U phase of the motor and the UL form a closed loop, current is generated in the loop, and absolute values of the current in A1, A2 and A3 are read and recorded and are expressed as IU3, IV3 and IW 3;

s4, conducting VH and UL for a fixed time t4, and simultaneously turning off other 4 IGBTs, wherein VH, a motor V phase, a motor U phase and UL form a closed loop, current is generated in the loop, and absolute values of the current in A1, A2 and A3 are read and recorded and are expressed as IU4, IV4 and IW 4;

s5, turning on the WH and the VL for a fixed time t5, and turning off other 4 IGBTs at the same time, wherein the WH, the W phase of the motor, the V phase of the motor and the VL form a closed loop, current is generated in the loop, and absolute values of the current in A1, A2 and A3 are read and recorded and are expressed as IU5, IV5 and IW 5;

and S6, conducting the UH and the WL for a fixed time t6, and simultaneously turning off the other 4 IGBTs, wherein the UH, the U phase of the motor, the W phase of the motor and the WL form a closed loop, current is generated in the loop, and absolute values of the current in A1, A2 and A3 are read and recorded and are expressed as IU6, IV6 and IW 6.

The correspondence between the IGBT on and the three-phase current is shown in table 1.

Serial number	Conducting IGBT	Absolute value of three-phase current
			1	UH、VL	IU1、IV1、IW1
2	VH、WL	IU2、IV2、IW2
			3	WH、UL	IU3、IV3、IW3
4	VH、UL	IU4、IV4、IW4
			5	WH、VL	IU5、IV5、IW5
6	UH、WL	IU6、IV6、IW6

TABLE 1

After the data is acquired, the fault judgment condition comprises the following steps:

p1, if IU1< Ithr, IU6< Ithr, and IU3 ≧ Ithr, or IU4 ≧ Ithr, determining UH open circuit;

p2, if IV2< Ithr, and IV4< Ithr, and (IV1 ≧ Ithr, or IV5 ≧ Ithr), determining VH open circuit;

p3, if IW3< Ithr, IW5< Ithr, and (IW2 ≧ Ithr, or IW6 ≧ Ithr), determining WH open circuit;

p4, if IU3< Ithr, IU4< Ithr, and (IU1 ≧ Ithr, or IU6 ≧ Ithr), determining UL open circuit;

p5, if IV1< Ithr, and IV5< Ithr, and (IV2 ≧ Ithr, or IV4 ≧ Ithr), then VL is considered open-circuited;

p6, if IW2< Ithr, and IW6< Ithr, and (IW3 ≧ Ithr, or IW5 ≧ Ithr), deeming WL open circuit;

p7, if IU1< Ithr, and IU6< Ithr, and IU3< Ithr, and IU4< Ithr, then U phase is deemed open;

p8, if IV2< Ithr, and IV4< Ithr, and IV1< Ithr, and IV5< Ithr, then V phase open is deemed;

p9, if IW3< Ithr, and IW5< Ithr, and IW2< Ithr, and IW6< Ithr, then W phase is deemed open.

Wherein Ithr is the current threshold.

The conditions for determining the IGBT open circuit and the three-phase motor open circuit are shown in table 2.

TABLE 2

In order to improve the detection accuracy, when the conduction time t1, t2, t3, t4, t5 and t6 are determined, the conduction current is greater than the current threshold Ithr under the condition that the IGBT and the motor are free of faults; in actual detection, t1, t2, t3, t4, t5 and t6 have the same value.

And after the fault is judged, secondary repeated detection is carried out, the results are compared for inspection, and the fault reason can be determined to be correct if the results of the three times are consistent.

Example two

In this embodiment, the correctness is automatically detected and verified by a disconnection detection system, which includes:

a data acquisition module: the detection device is electrically connected with the motor and used for collecting six groups of three-phase currents of the motor during detection;

an analysis and judgment module: the data acquisition module is connected, the data acquisition module analyzes the acquired three-phase current, judges whether the IGBT is broken or not and whether the three phases of the motor are broken or not according to the breaking judgment condition, and outputs a breaking signal when the judgment result is breaking;

an output display module: the connection analysis and judgment module is used for transmitting the circuit breaking signal to a controller of the motor and displaying the circuit breaking signal through a display device;

an alarm module: and the connection analysis and judgment module is used for alarming when the circuit is broken.

According to the invention, the IGBT open-circuit fault and the motor three-phase open-circuit fault can be identified through a program without disassembling the motor controller and the motor during open-circuit diagnosis, and the method is suitable for carrying out initialization diagnosis and maintenance diagnosis on the fault, and is convenient and rapid.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims (8)

1. A method for detecting IGBT open circuit and motor three-phase open circuit of a motor controller is characterized in that two IGBTs capable of forming a closed loop with a motor are conducted according to a specific sequence, the rest IGBTs are turned off, the absolute value of current is recorded, and the IGBT open circuit fault and the motor three-phase open circuit fault are analyzed and judged through six groups of three-phase current data.

2. The method for detecting the IGBT breaking and the three-phase breaking of the motor controller according to claim 1, wherein the absolute value of the current is recorded by turning on two of the IGBTs which can form a closed loop with the motor and turning off the rest of the IGBTs in a specific sequence, and the method comprises the following steps:

s1, conducting UH and VL for a fixed time t1, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, wherein the absolute values are expressed as IU1, IV1 and IW 1;

s2, turning on VH and WL for a fixed time t2, simultaneously turning off other 4 IGBTs, reading and recording the absolute values of currents in A1, A2 and A3, and expressing the absolute values as IU2, IV2 and IW 2;

s3, turning on WH and UL for a fixed time t3, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, wherein the absolute values are expressed as IU3, IV3 and IW 3;

s4, turning on VH and UL for a fixed time t4, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, and expressing the absolute values as IU4, IV4 and IW 4;

s5, turning on WH and VL for a fixed time t5, simultaneously turning off other 4 IGBTs, reading and recording absolute values of currents in A1, A2 and A3, wherein the absolute values are expressed as IU5, IV5 and IW 5;

and S6, conducting UH and WL for a fixed time t6, simultaneously turning off other 4 IGBTs, reading and recording the absolute values of currents in A1, A2 and A3, and expressing the absolute values as IU6, IV6 and IW 6.

3. The method as claimed in claim 2, wherein after the data is obtained, the fault determination comprises:

p1, if IU1< Ithr, IU6< Ithr, and IU3 ≧ Ithr, or IU4 ≧ Ithr, determining UH open circuit;

p2, if IV2< Ithr, and IV4< Ithr, and (IV1 ≧ Ithr, or IV5 ≧ Ithr), determining VH open circuit;

p3, if IW3< Ithr, IW5< Ithr, and (IW2 ≧ Ithr, or IW6 ≧ Ithr), determining WH open circuit;

p4, if IU3< Ithr, IU4< Ithr, and (IU1 ≧ Ithr, or IU6 ≧ Ithr), determining UL open circuit;

p5, if IV1< Ithr, and IV5< Ithr, and (IV2 ≧ Ithr, or IV4 ≧ Ithr), then VL is considered open-circuited;

p6, if IW2< Ithr, and IW6< Ithr, and (IW3 ≧ Ithr, or IW5 ≧ Ithr), deeming WL open circuit;

p7, if IU1< Ithr, and IU6< Ithr, and IU3< Ithr, and IU4< Ithr, then U phase is deemed open;

p8, if IV2< Ithr, and IV4< Ithr, and IV1< Ithr, and IV5< Ithr, then V phase open is deemed;

p9, if IW3< Ithr, and IW5< Ithr, and IW2< Ithr, and IW6< Ithr, then W phase is deemed open;

wherein Ithr is the current threshold.

4. The method as claimed in claim 2, wherein the turn-on time t1, t2, t3, t4, t5 and t6 is determined to ensure that the turn-on current is greater than the threshold current ith without the fault condition of the IGBT and the motor.

5. The motor controller IGBT shutdown and motor three-phase shutdown detection method as claimed in claim 4, wherein t1, t2, t3, t4, t5 and t6 are the same in value.

6. The method as claimed in claim 1, wherein the detection of IGBT break and three-phase break of motor controller is performed more than two times after the fault is determined, and the comparison result is used for inspection.

7. The method as claimed in claim 6, wherein the correctness is automatically detected and verified by a trip detection system.

8. The method as claimed in claim 7, wherein the trip detection system comprises:

a data acquisition module: the detection device is electrically connected with the motor and used for collecting six groups of three-phase currents of the motor during detection;

an analysis and judgment module: the data acquisition module is connected, the data acquisition module analyzes the acquired three-phase current, judges whether the IGBT is broken or not and whether the three phases of the motor are broken or not according to the breaking judgment condition, and outputs a breaking signal when the judgment result is breaking;

an output display module: the connection analysis and judgment module is used for transmitting the circuit breaking signal to a controller of the motor and displaying the circuit breaking signal through a display device;

an alarm module: and the connection analysis and judgment module is used for alarming when the circuit is broken.

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