Fault-tolerant driving control method of electro-excitation direct-current synchronous motor for electric automobile

Abstract

The invention discloses a fault-tolerant driving control method of an electro-magnetic direct-current synchronous motor for an electric automobile, and relates to the field of electro-magnetic direct-current synchronous motors, the electro-magnetic direct-current synchronous motor is electrically controlled by a normal strategy before a fault occurs, and is switched to a fault electric mode after an excitation fault occurs, and the fault electric mode is switched to a fault electric mode after the fault occurs. Wherein the fault-tolerant control of the main power converter switch tube is considered in the fault electric mode, the operation reliability of the four-phase electro-magnetic direct-current synchronous motor in various environments is improved, and the method is suitable for being applied to the industries of electric automobiles and the like.

Description

Technical Field

[0001] The invention relates to the field of electrically excited direct current synchronous motors, in particular to a fault-tolerant drive control method for electrically excited direct current synchronous motors for electric vehicles. Background Art

[0002] The electrically excited DC synchronous motor is a new type of brushless DC motor developed on the basis of the switched reluctance motor. Its stator is wound with armature winding and excitation winding, and there is no winding on the rotor. It has a simple and reliable structure and flexible control. The four-phase electrically excited DC synchronous motor has the advantages of good fault tolerance and suitability for harsh working conditions. It is very flexible to control and has broad application prospects in electric vehicles, aviation and other fields.

[0003] At present, there are few studies on fault-tolerant control strategies for excitation faults of four-phase electrically excited DC synchronous motors. In the prior art, there is a blank in the electric control fault-tolerant strategy for four-phase electrically excited DC synchronous motors, and there is still a blank in the need for further fault-tolerant control when the main power converter fails during excitation faults. In order to fill this gap, this paper studies a fault-tolerant drive control method for electrically excited DC synchronous motors for electric vehicles. Summary of the invention

[0004] In view of the above problems and technical requirements, the inventors have proposed a fault-tolerant drive control method for an electrically excited DC synchronous motor for electric vehicles, which can realize fault-tolerant control when a switch tube fails in the main power topology under an excitation fault. The technical solution of the present invention is as follows:

[0005] An electric fault-tolerant control strategy for an electrically excited DC synchronous motor includes a fault-tolerant topology, a four-phase electrically excited DC synchronous motor, a position sensor, a load, an energy storage capacitor C, a DC power supply U dc ;

[0006] DC power supply U dc The positive electrode is connected to the collector of the upper switch tube of each bridge arm in the fault-tolerant topology, and the DC power supply U dc The negative electrode is connected to the emitter of the lower switch tube of each bridge arm of the fault-tolerant topology;

[0007] The load is connected in parallel with the load energy storage capacitor and in parallel with the fault-tolerant topology, which consists of an H-bridge converter and four electronic switches.

[0008] The four-phase electrically excited DC synchronous motor is characterized in that the four groups of H-bridge converters have the same structure, each H-bridge converter includes a first bridge arm and a second bridge arm respectively composed of an upper switch tube and a lower switch tube connected in reverse series, and a diode is connected in reverse parallel to both ends of the lower switch tubes in the two bridge arms; at the same time, an electronic switch is connected between the positive end of the A-phase winding and the positive end of the C-phase winding, and an electronic switch is connected between the negative end of the A-phase winding and the negative end of the C-phase winding; an electronic switch is connected between the positive end of the B-phase winding and the positive end of the D-phase winding, and an electronic switch is connected between the negative end of the B-phase winding and the negative end of the D-phase winding;

[0009] The four-phase electrically excited DC synchronous motor is characterized in that the three-phase armature winding includes an A-phase winding, a B-phase winding, a C-phase winding, and a D-phase winding, the first H-bridge converter is connected to the A-phase winding, the second H-bridge converter is connected to the B-phase winding, the third H-bridge converter is connected to the C-phase winding, and the fourth H-bridge converter is connected to the D-phase winding.

[0010] When the four-phase electrically excited DC synchronous motor is working normally: when the current sensor does not detect an excitation fault, the four-phase electrically excited DC synchronous motor operates in a normal strategy state, the controller controls the electronic switches K1, K2, K3, and K4 to be disconnected, and the conduction logic during normal operation is adopted; when an excitation fault is detected in the four-phase electrically excited DC synchronous motor, the excitation circuit is disconnected, and a fault-tolerant strategy is adopted for fault-tolerant control.

[0011] The beneficial technical effects of the present invention are:

[0012] The present application discloses a fault-tolerant drive control method for an electrically excited DC synchronous motor for electric vehicles. Before an excitation fault occurs, the four-phase electrically excited DC synchronous motor turns off K1, K2, K3, and K4 to conduct normal motoring in a manner of "positive electricity is passed through the inductance rising phase and negative electricity is passed through the inductance falling phase". After an excitation fault occurs, the motor switches to a fault-tolerant mode, thereby improving the reliability of the four-phase electrically excited DC synchronous motor in various environments. The motor is suitable for use in the automotive and other industries.

[0013] In addition, the H-bridge converter used in the four-phase electrically excited DC synchronous motor helps to make each phase winding independent, and there is no problem of current gap caused by the change of midpoint potential, and the control strategy is more flexible. The motor power generation process no longer needs to be connected in series with the power consumption phase, which can improve the motor operation efficiency and has good fault tolerance performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a control structure diagram of the four-phase electrically excited DC synchronous motor of the present application.

[0015] Figure 2It is the converter topology conduction diagram when the motor electrical angle of the present application is in the interval of [0°, 90°) and the excitation fault of the four-phase electrically excited DC synchronous motor occurs and the switch tube in the fault-tolerant topology does not fail.

[0016] Figure 3 It is a schematic diagram of fault-tolerant control logic when the excitation fault occurs in the four-phase electrically excited DC synchronous motor of the present application and the switch tube in the fault-tolerant topology does not fail.

[0017] Figure 4 The converter topology conduction diagram of the four-phase electrically excited DC synchronous motor when the motor electrical angle of the present application is in the interval of [90°, 180°) is faulty in excitation and the switch tube S1 in the fault-tolerant topology fails.

[0018] Figure 5 It is a schematic diagram of fault-tolerant control logic when the excitation of the four-phase electrically excited DC synchronous motor of the present application fails and the switch tube S1 in the fault-tolerant topology fails.

[0019] Figure 6 The converter topology conduction diagram of the four-phase electrically excited DC synchronous motor of the present application when the motor electrical angle is in the interval of [0°, 90°) and the excitation fault of the switch tubes S13 and S14 in the fault-tolerant topology fails.

[0020] Figure 7 It is a schematic diagram of fault-tolerant control logic when the excitation of the four-phase electrically excited DC synchronous motor of the present application fails and the switch tubes S13 and S14 in the fault-tolerant topology fail. DETAILED DESCRIPTION

[0021] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0022] The present application discloses a fault-tolerant driving control method for an electrically excited DC synchronous motor for an electric vehicle, characterized in that the electric fault-tolerant control strategy of the electrically excited DC synchronous motor includes a fault-tolerant topology, a four-phase electrically excited DC synchronous motor, a position sensor, a load, an energy storage capacitor C, a DC power supply U dc ;

[0023] DC power supply U dc The positive electrode is connected to the collector of the upper switch tube of each bridge arm in the fault-tolerant topology, and the DC power supply U dc The negative electrode is connected to the emitter of the lower switch tube of each bridge arm of the fault-tolerant topology;

[0024] The load is connected in parallel with the load energy storage capacitor and in parallel with the fault-tolerant topology, which consists of an H-bridge converter and four electronic switches.

[0025] The four-phase electrically excited DC synchronous motor is characterized in that the four groups of H-bridge converters have the same structure, each H-bridge converter includes a first bridge arm and a second bridge arm respectively composed of an upper switch tube and a lower switch tube connected in reverse series, and a diode is connected in reverse parallel to both ends of the lower switch tubes in the two bridge arms; at the same time, an electronic switch is connected between the positive end of the A-phase winding and the positive end of the C-phase winding, and an electronic switch is connected between the negative end of the A-phase winding and the negative end of the C-phase winding; an electronic switch is connected between the positive end of the B-phase winding and the positive end of the D-phase winding, and an electronic switch is connected between the negative end of the B-phase winding and the negative end of the D-phase winding;

[0026] The four-phase electrically excited DC synchronous motor is characterized in that the three-phase armature winding includes an A-phase winding, a B-phase winding, a C-phase winding, and a D-phase winding, the first H-bridge converter is connected to the A-phase winding, the second H-bridge converter is connected to the B-phase winding, the third H-bridge converter is connected to the C-phase winding, and the fourth H-bridge converter is connected to the D-phase winding.

[0027] Combination Figure 1 The structure shown in the figure, the working process of the four-phase electrically excited DC synchronous motor is described as follows:

[0028] When the four-phase electrically excited DC synchronous motor is working normally: when the current sensor does not detect the excitation fault, the four-phase electrically excited DC synchronous motor operates in the normal strategy state, the controller controls the electronic switches K1, K2, K3, and K4 to be disconnected, and when the motor electrical angle is in the interval of [0°, 90°), S9, S2, S5, S14, S4, S11, S7, and S16 are controlled to be turned on; when the motor electrical angle is in the interval of [90°, 180°), S1, S10, S6, S13, S4, S11, S7, and S16 are controlled to be turned on; when the motor electrical angle is in the interval of [180°, 270°), S1, S10, S6, S13, S3, S12, S8, and S15 are controlled to be turned on; when the motor electrical angle is in the interval of [270°, 360°], S9, S2, S5, S14, S3, S12, S8, and S15 are controlled to be turned on.

[0029] When the current sensor detects an excitation fault, the controller disconnects the excitation circuit and switches to fault-tolerant mode. When the four-phase electrically excited DC synchronous motor has an excitation fault and the switch tube in the fault-tolerant topology does not fail, the converter topology conduction diagram and fault-tolerant conduction logic are as follows when the motor electrical angle is in the range of [0°, 90°]. Figure 2 and Figure 3 As shown:

[0030] First, the electronic switches K1, K2, K3, and K4 are controlled to be turned off. When the motor electrical angle is in the interval [0°, 90°), S5, S14, S7, and S16 are controlled to be turned on.

[0031] When the motor electrical angle is in the interval [90°, 180°), control S1, S10, S7, and S16 to be turned on;

[0032] When the motor electrical angle is in the range of [180°, 270°), control S1, S10, S3, and S12 to be turned on;

[0033] When the motor electrical angle is in the range of [270°, 360°], S5, S14, S3, and S12 are controlled to be turned on.

[0034] When the excitation fault of the four-phase electrically excited DC synchronous motor occurs and a single switch tube fault occurs in the fault-tolerant topology (taking S1 fault as an example, the rest of the cases are analogous). When the motor electrical angle is in the interval [90°, 180°), the converter topology conduction diagram and fault-tolerant conduction logic are as follows: Figure 4 and Figure 5 As shown:

[0035] First, the electronic switches K1, K2, K3, and K4 are controlled to be turned off. When the motor electrical angle is in the interval [0°, 90°), S5, S14, S7, and S16 are controlled to be turned on.

[0036] When the motor electrical angle is in the interval [90°, 180°), control S2, S9, S7, and S16 to be turned on;

[0037] When the motor electrical angle is in the range of [180°, 270°), control S2, S9, S3, and S12 to be turned on;

[0038] When the motor electrical angle is in the range of [270°, 360°], S5, S14, S3, and S12 are controlled to be turned on.

[0039] When the excitation fault of the four-phase electrically excited DC synchronous motor is detected and the switch tube in the fault-tolerant topology has a double-tube open circuit fault in the same bridge arm or a two-upper tube open circuit or two-lower tube open circuit fault in the same phase (taking phase C as an example, S13 and S14 are faulty, at this time, the AC winding conducts current in the opposite direction in the inductance rising area, and the rest of the cases are analogous). When the motor electrical angle is in the interval [0°, 90°), the converter topology conduction diagram and fault-tolerant conduction logic are as follows: Figure 6 and Figure 7 As shown:

[0040] First, the electronic switch K2 is controlled to be turned on, and K1, K3, and K4 are turned off. When the motor electrical angle is in the interval [0°, 90°), S6, S9, S7, and S16 are controlled to be turned on;

[0041] When the motor electrical angle is in the interval [90°, 180°), control S1, S10, S7, and S16 to be turned on;

[0042] When the motor electrical angle is in the range of [180°, 270°), control S1, S10, S3, and S12 to be turned on;

[0043] When the motor electrical angle is in the range of [270°, 360°], S6, S9, S3, and S12 are controlled to be turned on.

[0044] When the excitation fault of the four-phase electrically excited DC synchronous motor occurs and three or more switch tubes in the fault-tolerant topology are open (one phase in AC and one phase in BD, two phases open fault), (taking S13, S14; S15, S16 two-phase open fault as an example, and the rest are analogous), the fault-tolerant guidance logic is as follows:

[0045] First, the electronic switches K2 and K4 are controlled to be turned on, and K1 and K3 are turned off. When the motor electrical angle is in the interval [0°, 90°), S6, S9, S8, and S11 are controlled to be turned on;

[0046] When the motor electrical angle is in the interval [90°, 180°), control S1, S10, S8, and S11 to be turned on;

[0047] When the motor electrical angle is in the range of [180°, 270°), control S1, S10, S3, and S12 to be turned on;

[0048] When the motor electrical angle is in the range of [270°, 360°], S6, S9, S3, and S12 are controlled to be turned on.

[0049] In the process of controlling the state of the switching tube and the electronic switch in the fault-tolerant topology, the controller performs PI adjustment on the error between the actual speed and the given speed to obtain the given current, and then performs PI adjustment on the given current and the actual current of the current four-phase winding to obtain the corresponding duty cycle signal, and performs AND operation with the fault-tolerant conduction logic to perform chopping control on the current of the four-phase armature winding to achieve closed-loop control of the speed.

[0050] The above is only a preferred embodiment of the present application, and the present invention is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the protection scope of the present invention.

Claims

1. A fault-tolerant drive control method for an electrically excited DC synchronous motor for an electric vehicle, characterized in that: The electric fault-tolerant control strategy of the electrically excited DC synchronous motor includes a fault-tolerant topology, a four-phase electrically excited DC synchronous motor, a position sensor, a load, an energy storage capacitor C, a DC power supply U dc ; DC power supply U dc The positive electrode is connected to the collector of the upper switch tube of each bridge arm in the fault-tolerant topology, and the DC power supply U dc The negative electrode is connected to the emitter of the lower switch tube of each bridge arm of the fault-tolerant topology; The load is connected in parallel with the load energy storage capacitor and in parallel with the fault-tolerant topology, which consists of an H-bridge converter and four electronic switches.

2. The four-phase electrically excited DC synchronous motor according to claim 1, characterized in that: The structures of the four groups of H-bridge converters are the same. Each H-bridge converter includes a first bridge arm and a second bridge arm respectively composed of an upper switch tube and a lower switch tube connected in reverse series, and a diode is connected in reverse parallel at both ends of the lower switch tubes in the two bridge arms; at the same time, an electronic switch is connected between the positive end of the A-phase winding and the positive end of the C-phase winding, and an electronic switch is connected between the negative end of the A-phase winding and the negative end of the C-phase winding; an electronic switch is connected between the positive end of the B-phase winding and the positive end of the D-phase winding, and an electronic switch is connected between the negative end of the B-phase winding and the negative end of the D-phase winding.

3. The four-phase electrically excited DC synchronous motor according to claim 1, characterized in that: The three-phase armature winding includes an A-phase winding, a B-phase winding, a C-phase winding, and a D-phase winding. The first H-bridge converter is connected to the A-phase winding, the second H-bridge converter is connected to the B-phase winding, the third H-bridge converter is connected to the C-phase winding, and the fourth H-bridge converter is connected to the D-phase winding. When the excitation of the four-phase electrically excited DC synchronous motor is normal, the controller controls the electronic switches K1, K2, K3, and K4 to be disconnected. When the motor electrical angle is in the interval of [0°, 90°), S9, S2, S5, S14, S4, S11, S7, and S16 are controlled to be turned on; when the motor electrical angle is in the interval of [90°, 180°), S1, S10, S6, S13, S4, S11, S7, and S16 are controlled to be turned on; when the motor electrical angle is in the interval of [180°, 270°), S1, S10, S6, S13, S3, S12, S8, and S15 are controlled to be turned on; when the motor electrical angle is in the interval of [270°, 360°], S9, S2, S5, S14, S3, S12, S8, and S15 are controlled to be turned on. When the excitation of the four-phase electrically excited DC synchronous motor fails and the switch tube in the fault-tolerant topology does not fail, the fault-tolerant guidance logic is as follows: First, the electronic switches K1, K2, K3, and K4 are controlled to be turned off. When the motor electrical angle is in the interval [0°, 90°), S5, S14, S7, and S16 are controlled to be turned on. When the motor electrical angle is in the interval [90°, 180°), control S1, S10, S7, and S16 to be turned on; When the motor electrical angle is in the range of [180°, 270°), S1, S10, S3, and S12 are controlled to be turned on; when the motor electrical angle is in the range of [270°, 360°], S5, S14, S3, and S12 are controlled to be turned on. When the excitation fault of the four-phase electrically excited DC synchronous motor occurs and a single switch tube fault occurs in the fault-tolerant topology (taking S1 fault as an example, and the rest of the cases are analogous), the fault-tolerant guidance logic is as follows: First, the electronic switches K1, K2, K3, and K4 are controlled to be turned off. When the motor electrical angle is in the interval [0°, 90°), S5, S14, S7, and S16 are controlled to be turned on. When the motor electrical angle is in the interval [90°, 180°), control S2, S9, S7, and S16 to be turned on; When the motor electrical angle is in the range of [180°, 270°), control S2, S9, S3, and S12 to be turned on; When the motor electrical angle is in the range of [270°, 360°], S5, S14, S3, and S12 are controlled to be turned on. When the excitation fault of the four-phase electrically excited DC synchronous motor occurs and the switch tube in the fault-tolerant topology has a double-tube open circuit fault in the same bridge arm or a switch tube has two upper tubes open circuit or two lower tubes open circuit faults on the same phase (taking phase C as an example, S13 and S14 failure as an example, at this time, the AC winding passes current in the opposite direction in the inductance rising area, and the rest of the cases are analogous), the fault-tolerant conduction logic is as follows: First, the electronic switch K2 is controlled to be turned on, and K1, K3, and K4 are turned off. When the motor electrical angle is in the interval [0°, 90°), S6, S9, S7, and S16 are controlled to be turned on; When the motor electrical angle is in the interval [90°, 180°), control S1, S10, S7, and S16 to be turned on; When the motor electrical angle is in the range of [180°, 270°), control S1, S10, S3, and S12 to be turned on; When the motor electrical angle is in the range of [270°, 360°], S6, S9, S3, and S12 are controlled to be turned on. When the excitation fault of the four-phase electrically excited DC synchronous motor occurs and three or more switch tubes in the fault-tolerant topology are open (one phase in AC and one phase in BD, two phases open fault), (taking S13, S14; S15, S16 two-phase open fault as an example, and the rest are analogous), the fault-tolerant guidance logic is as follows: First, the electronic switches K2 and K4 are controlled to be turned on, and K1 and K3 are turned off. When the motor electrical angle is in the interval [0°, 90°), S6, S9, S8, and S11 are controlled to be turned on; When the motor electrical angle is in the interval [90°, 180°), control S1, S10, S8, and S11 to be turned on; When the motor electrical angle is in the range of [180°, 270°), control S1, S10, S3, and S12 to be turned on; When the motor electrical angle is in the range of [270°, 360°], S6, S9, S3, and S12 are controlled to be turned on.

4. The four-phase electrically excited DC synchronous motor according to claim 1, characterized in that: In the process of controlling the states of the switching tubes and electronic switches in the fault-tolerant topology, the controller performs PI adjustment on the error between the actual speed and the given speed to obtain the given current, and then performs PI adjustment on the given current and the actual current of the current four-phase winding to obtain the corresponding duty cycle signal, and performs AND operation with the fault-tolerant conduction logic to perform chopping control on the current of the four-phase armature winding to achieve closed-loop control of the speed.

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