Composite winding five-phase induction motor frequency conversion power supply circuit based on state machine control

Abstract

The invention relates to a composite winding five-phase induction motor frequency conversion power supply circuit based on state machine control. The power supply circuit is composed of a power supply voltage source, power electronic devices IGBT and diodes, a triangular wave signal generator, a sine wave signal generator, a state machine, a power supply circuit and a composite winding five-phase induction motor. A power supply of the circuit is formed by connecting two direct-current voltage sources E1 and E2 in series, a positive-polarity power circuit and a negative-polarity power circuit are led out, meanwhile, the midpoints of the two direct-current voltage sources are grounded, the positive polarity and the negative polarity led out of the power circuit are connected with an inverter circuit, and the five-phase induction motor composite winding is connected in a star-pentagon mode. A, B, C, D and E phase windings on the star-shaped side are respectively connected with midpoints of corresponding bridge arms of the inverter circuit.

Description

Technical Field

[0001] The invention relates to a variable frequency power supply circuit of a composite winding five-phase induction motor based on state machine control, belonging to the technical field of motor control. Background Art

[0002] Compared with the traditional three-phase induction motor, the five-phase induction motor has a much stronger fault tolerance due to the increase in the number of phases. Even if one or more windings fail, the motor can continue to run and provide a greater load torque. The five-phase induction motor can also distribute the load more evenly, reduce losses, and improve efficiency. However, the increase in the number of phases makes the power supply form of the five-phase induction motor more complicated. The common power supply circuit uses power electronic devices and switches in series to control the flow of current. There are many devices required, and it is easy to cause voltage or current overshoot during the opening and closing of the switch. The use of a state machine to control the opening and closing of power electronic devices can solve the overcharging problem, and the control logic is clear, which can also weaken the introduced high-order harmonics. Summary of the invention

[0003] The object of the present invention is to provide a variable frequency power supply circuit for a five-phase induction motor with a composite winding based on a state machine control, so that the logic of the power supply circuit control method is simple and clear, and at the same time, the high-order harmonics introduced by the switching device are effectively weakened.

[0004] The technical solution for achieving the above-mentioned purpose of the present invention is: a variable frequency power supply circuit for a composite winding five-phase induction motor based on state machine control, which is composed of a DC voltage source, power electronic devices IGBT and diode, a triangle wave signal generator, a sine wave signal generator, a state machine, a power supply line, and a composite winding five-phase induction motor.

[0005] The power supply of the circuit is composed of two DC voltage sources E1 and E2 connected in series, and the positive and negative polarity power supply lines are led out. The midpoint of E1 and E2 is grounded, and the positive and negative polarities of the led-out power supply lines are connected to the inverter circuit. The windings of the corresponding phases of the five-phase induction motor are respectively connected to the midpoints of the corresponding bridge arms, and the connection form of the composite winding of the five-phase induction motor is star-pentagon.

[0006] The five sine wave signal generators SINE1, SINE2, SINE3, SINE4, and SINE5 generate sine wave signals (modulation waves) which are compared with the high-frequency triangle wave signals (carrier waves) generated by the triangle wave signal generator TRIANG. When the sine wave signal value is greater than or equal to or less than or equal to a certain set triangle wave signal value, the state of the state machine is changed (such as STATE1_1 is 1 and STATE1_2 is 0). The change of the state machine state triggers the corresponding IGBT to turn on and off (IGBT1 turns on and IGBT2 turns off).

[0007] The opening and closing of the IGBT on each bridge arm is controlled by the STATE of the corresponding state machine. STATE1_1, STATE1_2, STATE2_3, STATE2_4, STATE3_5, STATE3_6, STATE4_7, STATE4_8, STATE5_9, and STATE5_10 respectively control the opening and closing of IGBT1, IGBT2, IGBT3, IGBT4, IGBT5, IGBT6, IGBT7, IGBT8, IGBT9, and IGBT10.

[0008] The inverter circuit is composed of power electronic devices IGBT and diodes according to a certain connection relationship. IGBT1 and IGBT2, IGBT3 and IGBT4, IGBT5 and IGBT6, IGBT7 and IGBT8, IGBT9 and IGBT10 respectively form the upper bridge arm and lower bridge arm of the first bridge arm, the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm. The emitter of the upper bridge arm is connected to the collector of the lower bridge arm, and a reverse parallel connection is connected at both ends of IGBT1, IGBT2, IGBT3, IGBT4, IGBT5, IGBT6, IGBT7, IGBT8, IGBT9, and IGBT10. The corresponding diodes are D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10. The cathode of the diode is connected to the collector of the corresponding IGBT, and the anode is connected to the emitter. The reverse-parallel diode can improve the switching speed and reliability of the circuit, reduce the reverse leakage current, suppress the back electromotive force, and improve the response speed of the inverter circuit. The collector of the upper bridge arm IGBT1, IGBT3, IGBT5, IGBT7, and IGBT9 is connected to the positive polarity power line, and the emitter of the lower bridge arm IGBT2, IGBT4, IGBT6, IGBT8, and IGBT10 is connected to the negative polarity power line.

[0009] The winding connection form of the composite winding five-phase induction motor is star-pentagon, the star-shaped A-phase winding is connected to the midpoint of IGBT1 and IGBT2, the B-phase winding is connected to the midpoint of IGBT3 and IGBT4, the C-phase winding is connected to the midpoint of IGBT5 and IGBT6, the D-phase winding is connected to the midpoint of IGBT7 and IGBT8, and the E-phase winding is connected to the midpoint of IGBT9 and IGBT10.

[0010] The working principle of the present invention is: a triangle wave signal generator (TRIANG1) and a sine wave signal generator (SINE1, SINE2, SINE3, SINE4, SINE5) generate signals and use them as a carrier signal (triangle wave) and a modulation wave signal (sine wave), respectively. The signal values ​​of the two are compared and compared with the values ​​set in advance. When the set conditions are met, the corresponding state machine changes the current state, and the change of the state machine state triggers the opening or closing of the corresponding IGBT, thereby achieving the purpose of changing the current flow path, and then supplying power to the composite winding five-phase induction motor.

[0011] The present invention has the following beneficial effects:

[0012] 1. The present invention uses a state machine to control the switching and conduction of power electronic devices, and the logic is simple and clear.

[0013] 2. The present invention effectively weakens the high-order harmonics introduced by variable frequency power supply.

[0014] 3. The present invention provides a certain reference for the design of variable frequency power supply circuits for multi-phase motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 For signal generator and state machine

[0016] Figure 2 Circuit connection diagram

[0017] Figure 3 A five-phase induction motor and its winding connection diagram

[0018] Figure 4 The overall connection diagram

[0019] Figure 5 A phase current diagram

[0020] Figure 6 The harmonic spectrum of the A-phase current Fourier decomposition DETAILED DESCRIPTION

[0021] Two DC voltage sources E1 and E2 are connected in series, and the midpoint of the voltage source is grounded. The positive and negative polarity lines are led out, and the led power lines are connected to the inverter circuit. The A, B, C, D, and E phases of the composite winding five-phase motor are connected to the midpoint of each bridge arm of the inverter circuit respectively. The performance of the composite winding five-phase motor is tested, and the current data of each phase of the composite winding five-phase induction motor is obtained. The A phase current is Fourier decomposed, and f 0 is the modulation wave frequency, f 1 is the carrier frequency, and the harmonic spectrum is obtained. The results show that the high-order harmonics are effectively weakened.

Claims

1. A variable frequency power supply circuit for a five-phase induction motor with a composite winding based on state machine control, characterized in that: The power supply circuit is composed of a DC voltage source, power electronic devices IGBT and diode, a triangle wave signal generator, a sine wave signal generator, a state machine, a power supply line, and a composite winding five-phase induction motor.

2. The variable frequency power supply circuit of a five-phase induction motor with a composite winding based on state machine control according to claim 1 is characterized in that: The power supply of the circuit is composed of two DC voltage sources E1 and E2 connected in series, and the positive and negative polarity power supply lines are led out. The midpoint of E1 and E2 is grounded, and the positive and negative polarities of the led-out power supply lines are connected to the inverter circuit. The windings of the corresponding phases of the five-phase induction motor are respectively connected to the midpoints of the corresponding bridge arms, and the connection form of the composite winding of the five-phase induction motor is star-pentagon.

3. The variable frequency power supply circuit of a five-phase induction motor with a composite winding based on state machine control according to claim 1 is characterized in that: The five sine wave signal generators SINE1, SINE2, SINE3, SINE4, and SINE5 generate sine wave signals (modulation waves) which are compared with the high-frequency triangle wave signals (carrier waves) generated by the triangle wave signal generator TRIANG. When the sine wave signal value is greater than or equal to or less than or equal to a certain set triangle wave signal value, the state of the state machine is changed (such as STATE1_1 is 1 and STATE1_2 is 0). The change of the state machine state triggers the corresponding IGBT to turn on and off (IGBT1 turns on and IGBT2 turns off).

4. The variable frequency power supply circuit of a five-phase induction motor with a composite winding based on state machine control according to claim 1 is characterized in that: The opening and closing of the IGBT on each bridge arm is controlled by the STATE of the corresponding state machine. STATE1_1, STATE1_2, STATE2_3, STATE2_4, STATE3_5, STATE3_6, STATE4_7, STATE4_8, STATE5_9, and STATE5_10 respectively control the opening and closing of IGBT1, IGBT2, IGBT3, IGBT4, IGBT5, IGBT6, IGBT7, IGBT8, IGBT9, and IGBT10.

5. The variable frequency power supply circuit of a five-phase induction motor with a composite winding based on state machine control according to claim 1 is characterized in that: The inverter circuit is composed of power electronic devices IGBT and diodes according to a certain connection relationship. IGBT1 and IGBT2, IGBT3 and IGBT4, IGBT5 and IGBT6, IGBT7 and IGBT8, IGBT9 and IGBT10 respectively form the upper bridge arm and lower bridge arm of the first bridge arm, the second bridge arm, the third bridge arm, the fourth bridge arm, and the fifth bridge arm. The emitter of the upper bridge arm is connected to the collector of the lower bridge arm, and a reverse parallel connection is connected at both ends of IGBT1, IGBT2, IGBT3, IGBT4, IGBT5, IGBT6, IGBT7, IGBT8, IGBT9, and IGBT10. The corresponding diodes are D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10. The cathode of the diode is connected to the collector of the corresponding IGBT, and the anode is connected to the emitter. The reverse-parallel diode can improve the switching speed and reliability of the circuit, reduce the reverse leakage current, suppress the back electromotive force, and improve the response speed of the inverter circuit. The collector of the upper bridge arm IGBT1, IGBT3, IGBT5, IGBT7, and IGBT9 is connected to the positive polarity power line, and the emitter of the lower bridge arm IGBT2, IGBT4, IGBT6, IGBT8, and IGBT10 is connected to the negative polarity power line.

6. The variable frequency power supply circuit of a five-phase induction motor with a composite winding based on state machine control according to claim 1, characterized in that: The winding connection form of the composite winding five-phase induction motor is star-pentagon, the star-shaped A-phase winding is connected to the midpoint of IGBT1 and IGBT2, the B-phase winding is connected to the midpoint of IGBT3 and IGBT4, the C-phase winding is connected to the midpoint of IGBT5 and IGBT6, the D-phase winding is connected to the midpoint of IGBT7 and IGBT8, and the E-phase winding is connected to the midpoint of IGBT9 and IGBT10.

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