阅读说明：本技术 一种三相三线制开关磁阻电机驱动系统、控制方法及应用 (Three-phase three-wire system switched reluctance motor driving system, control method and application ) 是由 李惊 于 2020-07-30 设计创作，主要内容包括：本发明属于电力电子与微机控制技术为基础的磁机电一体化技术领域,公开了一种三相三线制开关磁阻电机驱动系统、控制方法及应用,设置开关磁阻电机定子,开关磁阻电机定子有n个定子凸极,每个凸极上绕有独立的凸极线圈；6个开关管组成的三相全桥功率转换电路,三相全桥功率转换电路与直流电源相连；控制器,控制三相全桥功率转换电路中的6个开关管开通或关闭。本发明采用6个开关管组成的三相全桥式功率转换电路拓扑结构,电机绕组按一定磁极顺序以星形型或者三角接法相连接并引出三根接线。与采用12个开关管的结构相比,结构功率元件少了一倍,降低了生产成本；与目前工业通用三相三线的接线方法兼容,极大提高了通用性和易用性。(The invention belongs to the technical field of magnetic-mechanical-electrical integration based on power electronics and microcomputer control technology, and discloses a three-phase three-wire system switched reluctance motor driving system, a control method and application, wherein a switched reluctance motor stator is arranged, the switched reluctance motor stator is provided with n stator salient poles, and each salient pole is wound with an independent salient pole coil; the three-phase full-bridge power conversion circuit consists of 6 switching tubes and is connected with a direct-current power supply; and the controller controls 6 switching tubes in the three-phase full-bridge power conversion circuit to be switched on or switched off. The invention adopts a three-phase full-bridge power conversion circuit topological structure consisting of 6 switching tubes, and motor windings are connected in a star-shaped or triangular connection mode according to a certain magnetic pole sequence and lead out three wires. Compared with the structure adopting 12 switching tubes, the structure has one time less power elements, thereby reducing the production cost; the method is compatible with the current industrial universal three-phase three-wire wiring method, and greatly improves the universality and the usability.)

1. A three-phase three-wire system switched reluctance motor driving system is characterized in that the three-phase three-wire system switched reluctance motor driving system is provided with a switched reluctance motor stator, the switched reluctance motor stator is provided with n stator salient poles, and each salient pole is wound with an independent salient pole coil;

the three-phase full-bridge power conversion circuit consists of 6 switching tubes and is connected with a direct current power supply;

and the controller controls 6 switching tubes in the three-phase full-bridge power conversion circuit to be switched on or switched off.

2. The three-phase three-wire system switched reluctance motor driving system of claim 1, wherein the a-phase winding of the motor is constructed by connecting the ends of 4 salient-pole coils a1, a2, A3, a4, 4 salient-pole coils, which are equally distributed on the circumference of the stator.

3. The three-phase three-wire system switched reluctance motor driving system of claim 2, wherein when a current flows from the positive terminal of the a1 coil into the negative terminal of the a4 coil, the magnetic field generated by the current in the coil causes the magnetic poles of the corresponding 4 salient pole coils a1, a2, A3, a4 to be arranged in N, S, N, S.

4. The three-phase three-wire system switched reluctance motor driving system of claim 2, wherein the ends of 4 salient-pole coils B1, B2, B3, B4 adjacent to each salient-pole coil in the a-phase winding are connected together to constitute a B-phase winding of the motor.

5. The three-phase three-wire system switched reluctance motor driving system of claim 4, wherein when a current flows from the positive terminal of the B1 coil into and out of the negative terminal of the B4 coil, the magnetic field generated by the current in the coil causes the corresponding poles of the 4 salient poles B1, B2, B3, B4 to be arranged in N, S, N, S.

6. The three-phase three-wire system switched reluctance motor driving system of claim 4, wherein 4 salient-pole coils C1, C2, C3, C4 adjacent to each salient-pole coil in the B-phase winding are connected together to constitute a C-phase winding of the motor.

7. The three-phase three-wire system switched reluctance motor driving system of claim 6, wherein when a current flows from the positive terminal of the C1 coil to the negative terminal of the C4 coil, the magnetic field generated by the current in the coil causes the corresponding 4 salient poles C1, C2, C3, C4 to be arranged in N, S, N, S.

8. The three-phase three-wire system switched reluctance motor driving system of claim 1, wherein an initial angle of a rotor corresponding to the stator of the switched reluctance motor is set to θ = 0 °;

when theta is more than or equal to 0 degree and less than or equal to 15 degrees, the switching tube Q1 and the switching tube Q4 are controlled to be conducted;

when theta is more than or equal to 15 degrees and less than or equal to 30 degrees, the switching tube Q5 and the switching tube Q4 are controlled to be conducted;

when theta is more than or equal to 30 degrees and less than or equal to 45 degrees, the switching tube Q5 and the switching tube Q2 are controlled to be conducted;

when theta is more than or equal to 45 degrees and less than or equal to 60 degrees, the switching tube Q3 and the switching tube Q2 are controlled to be conducted;

when theta is more than or equal to 60 degrees and less than or equal to 75 degrees, the switching tube Q3 and the switching tube Q6 are controlled to be conducted;

when theta is larger than or equal to 75 degrees and smaller than or equal to 90 degrees, the switching tube Q1 and the switching tube Q6 are controlled to be conducted.

9. A control method of a three-phase three-wire system switched reluctance motor driving system according to any one of claims 1 to 8, wherein a control program of the control method of the three-phase three-wire system switched reluctance motor driving system outputs a control waveform with a mechanical angle of 90 ° as one electrical cycle in accordance with the turn-on control sequence, and the high level is on and the low level is off to control the turn-on and turn-off of the corresponding switching tube; forming continuous rotary reluctance torque to enable the motor to run; the control program controls the phase current through the PWM signal, and the purpose of controlling the rotating speed of the motor is achieved.

10. A switched reluctance motor characterized in that the switched reluctance motor is mounted with the three-phase three-wire system switched reluctance motor driving system of claim 9.

Technical Field

The invention belongs to the technical field of magnetic, mechanical and electrical integration based on power electronics and microcomputer control technology, and particularly relates to a three-phase three-wire system switched reluctance motor driving system, a control method and application.

Background

At present, the switched reluctance motor is widely accepted by the industry due to high reliability, good energy-saving effect and relatively low motor cost. For the topology structure of the power conversion circuit of the switched reluctance motor driver, an asymmetric bridge type power conversion circuit is adopted for current conversion at present. The controller needs to use 12 switch tubes to independently control the three-phase windings of the motor. This control method requires more power elements, which increases the manufacturing cost. In this control scheme, the two ends of each phase winding need to be connected to the driver simultaneously, thus requiring the use of six cables. The method is incompatible with the 3-phase 3-wire wiring method generally adopted by the industry at present, and has poor universality. Because the phase winding works under independent control, a large radial force can be generated at the moment of excitation turn-off, so that the noise of the motor is increased.

Through the above analysis, the problems and defects of the prior art are as follows:

(1) the existing power conversion circuit of the switch reluctance motor driver needs to use more power elements, thereby increasing the manufacturing cost

(2) The existing switch reluctance motor driver power conversion circuit is incompatible with the 3-phase 3-wire wiring method generally adopted in the industry at present, and the universality is poor.

(3) Because the phase winding works under independent control, a large radial force can be generated at the moment of excitation turn-off, so that the noise of the motor is increased.

The difficulty in solving the above problems and defects is: because the flux linkage of the switched reluctance motor has highly nonlinear characteristics, the flux linkage characteristics can be greatly changed in different excitation modes, the switched reluctance motor works in the three-wire winding excitation mode, because two-phase windings are excited simultaneously to generate torque, the flux linkage characteristics of the switched reluctance motor are greatly changed compared with a single-phase excitation control mode controlled by 6 wires by analyzing a synthesized flux linkage of the two-phase windings, and the controller software needs to match the flux linkage characteristics to achieve a better working state.

The significance of solving the problems and the defects is as follows: the manufacturing cost of the controller is reduced, the usability is improved, and the noise and the vibration of the motor are improved.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a three-phase three-wire system switched reluctance motor driving system, a control method and application.

The invention is realized in this way, a three-phase three-wire system switch reluctance motor driving system, set up the stator of the switch reluctance motor, the stator of the switch reluctance motor has n stator salient poles, wind the independent salient pole coil on each salient pole;

the three-phase full-bridge power conversion circuit consists of 6 switching tubes and is connected with a direct current power supply;

and the controller controls 6 switching tubes in the three-phase full-bridge power conversion circuit to be switched on or switched off.

Furthermore, the ends of 4 salient pole coils A1, A2, A3, A4 and 4 salient pole coils which are evenly distributed on the circumference of the stator are connected together to form an A-phase winding of the motor.

Further, when current flows from the positive terminal of the a1 coil to the negative terminal of the a4 coil, the magnetic field generated by the current in the coil causes the corresponding poles of the 4 salient pole coils a1, a2, A3, a4 to be arranged in N, S, N, S.

Further, the ends of 4 salient-pole coils B1, B2, B3, B4 adjacent to the respective salient-pole coils in the a-phase winding are connected together to constitute a B-phase winding of the motor.

Further, when current flows from the positive terminal of the B1 coil to the negative terminal of the B4 coil, the magnetic field generated by the current in the coil causes the corresponding 4 salient poles B1, B2, B3, B4 to be arranged in N, S, N, S.

Further, 4 salient pole coils C1, C2, C3 and C4 adjacent to each salient pole coil in the B-phase winding are connected together to constitute a C-phase winding of the motor.

Further, when current flows from the positive terminal of the C1 coil to the negative terminal of the C4 coil, the magnetic field generated by the current in the coil causes the corresponding 4 salient poles C1, C2, C3, and C4 to be arranged in N, S, N, S.

Further, an initial angle of a rotor corresponding to the switched reluctance motor stator is set to be θ = 0 °;

when theta is more than or equal to 0 degree and less than or equal to 15 degrees, the switching tube Q1 and the switching tube Q4 are controlled to be conducted;

when theta is more than or equal to 15 degrees and less than or equal to 30 degrees, the switching tube Q5 and the switching tube Q4 are controlled to be conducted;

when theta is more than or equal to 30 degrees and less than or equal to 45 degrees, the switching tube Q5 and the switching tube Q2 are controlled to be conducted;

when theta is more than or equal to 45 degrees and less than or equal to 60 degrees, the switching tube Q3 and the switching tube Q2 are controlled to be conducted;

when theta is more than or equal to 60 degrees and less than or equal to 75 degrees, the switching tube Q3 and the switching tube Q6 are controlled to be conducted;

when theta is larger than or equal to 75 degrees and smaller than or equal to 90 degrees, the switching tube Q1 and the switching tube Q6 are controlled to be conducted.

Another object of the present invention is to provide a control method of the three-phase three-wire system switched reluctance motor driving system, in which a control program of the control method of the three-phase three-wire system switched reluctance motor driving system outputs a control waveform with a mechanical angle of 90 ° as one electrical cycle according to the turn-on control sequence, with a high level being on and a low level being off, controlling the turn-on and turn-off of the corresponding switching tubes. The motor is operated by forming a continuous rotating reluctance torque. The control program controls the phase current through the PWM signal, and the purpose of controlling the rotating speed of the motor is achieved.

Another object of the present invention is to provide a switched reluctance motor mounted with the three-phase three-wire system switched reluctance motor driving system.

By combining all the technical schemes, the invention has the advantages and positive effects that:

firstly, the invention adopts a three-phase full-bridge power conversion circuit topological structure consisting of 6 switching tubes, and motor windings are connected in a star-shaped or triangular connection mode according to a certain magnetic pole sequence and lead out three wires. Compared with the structure adopting 12 switching tubes, the power elements of the structure are reduced by one time, and the production cost is reduced.

Secondly, the wiring of the motor is compatible with the current industrial general three-phase three-wire wiring method, and the universality and the usability of the switched reluctance motor are greatly improved.

Thirdly, the winding excitation mode of the invention is two phases of three phases are alternately and simultaneously excited, the excitation mode only turns off one phase of winding when the phases are changed, and the generated instantaneous back electromotive force is negative 1/2 power voltage, while the instantaneous back electromotive force generated when the winding excitation is turned off is negative power voltage under the traditional 6-wire excitation mode, thus relieving the instantaneous sudden change of radial force when the switching tube is turned off and reducing the vibration and noise of the motor.

The back electromotive force generated by the winding which is switched off in the phase change of the excitation mode is half of the power supply voltage.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained from the drawings without creative efforts.

Fig. 1 is a schematic diagram of a three-phase three-wire system switched reluctance motor driving system according to an embodiment of the present invention.

Fig. 2 is a schematic circuit structure connection diagram of a three-phase three-wire system switched reluctance motor driving system according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of a logic waveform of a control timing of a switching tube according to an embodiment of the present invention.

Fig. 4 is a schematic view of a rotor mechanical angle and a power-on state according to an embodiment of the present invention.

Fig. 5 is a schematic view of a rotor mechanical angle and a power-on state according to an embodiment of the present invention.

Fig. 6 is a schematic view of a rotor mechanical angle and a power-on state according to an embodiment of the present invention.

Fig. 7 is a schematic view of a rotor mechanical angle and a power-on state according to an embodiment of the present invention.

Fig. 8 is a schematic view of a rotor mechanical angle and a power-on state according to an embodiment of the present invention.

Fig. 9 is a schematic view of a rotor mechanical angle and a power-on state according to an embodiment of the present invention.

In fig. 1 and 2: 1. a phase A winding; 2. a B-phase winding; 3. a C-phase winding; 4. a switching tube; 5. a stator salient-pole coil; 6. stator salient poles; 7. and a switch tube.

Fig. 10 is a diagram illustrating simulation results provided by an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In view of the problems in the prior art, the present invention provides a three-phase three-wire system switched reluctance motor driving system, a control method and an application thereof, and the present invention is described in detail below with reference to the accompanying drawings.

The three-phase three-wire system switched reluctance motor driving system is provided with n stator salient poles of a switched reluctance motor stator, and each salient pole is wound with an independent salient pole coil, wherein n =12 is taken as an example.

The ends of 4 salient pole coils A1, A2, A3 and A4 which are evenly distributed on the circumference of the stator are connected together to form an A-phase winding of the motor. The connection mode of the 4 salient-pole coils A1, A2, A3 and A4 requires that: when current flows from the positive terminal of the A1 coil to the negative terminal of the A4 coil, the magnetic field generated by the current in the coil makes the corresponding 4 salient poles A1, A2, A3 and A4 arranged in N, S, N, S.

The ends of 4 salient pole coils B1, B2, B3 and B4 adjacent to each salient pole coil in the phase a winding are connected together to form a phase B winding of the motor. Furthermore, the connection mode of the 4 salient-pole coils B1, B2, B3 and B4 requires that: when current flows from the positive terminal of the B1 coil to the negative terminal of the B4 coil, the magnetic field generated by the current in the coil makes the magnetic poles of the corresponding 4 salient poles B1, B2, B3 and B4 arranged in N, S, N, S.

The 4 salient pole coils C1, C2, C3 and C4 adjacent to each salient pole coil in the B-phase winding are connected together to form the C-phase winding of the motor. Furthermore, the connection mode of the 4 salient-pole coils C1, C2, C3 and C4 requires that: when current flows from the positive terminal of the C1 coil to the negative terminal of the C4 coil, the magnetic field generated by the current in the coil makes the magnetic poles of the corresponding 4 salient poles C1, C2, C3 and C4 arranged in N, S, N, S.

The negative terminals of the coils a4, B4, C4 are connected together (star connection), or the negative terminals of the coils a4, B4, C4 are connected to the positive terminals of the coils C1, a1, B1, respectively (delta connection).

The three-phase direct-current power conversion circuit is provided with a 3-phase full-bridge power conversion circuit consisting of 6 switching tubes Q1-Q6, and the 3-phase full-bridge power conversion circuit is connected with a direct-current power supply. And respectively connecting the positive terminals of the coils A1, B1 and C1 with the central points of three bridge arms of the three-phase full-bridge power conversion circuit by three motor connecting wires.

The three-phase full bridge power supply is provided with a controller, and the controller controls 6 switching tubes in the three-phase full bridge to be switched on or switched off. The controller is internally provided with a control program which controls the motor winding to be electrified or shut down according to a certain angle and sequence according to the position information of the rotor position sensor.

Taking a 12-8 pole motor as an example:

1) the rotor angle at this time is set to an initial angle of θ = 0 °, setting the adjacent two salient poles of the rotor to be aligned with the stator A, C phase winding salient poles. As shown in fig. 4: when theta is larger than or equal to 0 degree and smaller than or equal to 15 degrees, the switching tubes Q1 and Q4 are controlled to be conducted, current flows in from the A-phase winding and flows out from the B-phase winding, and the conducting direction is A-B. At this time, A, B two-phase windings are excited, and the rotor generates counterclockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the stator salient poles of A, B two phases and the flux linkage reluctance is minimum.

2) As shown in FIG. 5, when theta is larger than or equal to 15 degrees and smaller than or equal to 30 degrees, the switching tubes Q5 and Q4 are controlled to be conducted, current flows in from the C-phase winding, and flows out from the B-phase winding, and the conducting direction is C-B. At this time, C, B two-phase windings are excited, and the rotor generates counterclockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the stator salient poles of C, B two phases and the flux linkage reluctance is minimum.

3) As shown in fig. 6: when theta is larger than or equal to 30 degrees and smaller than or equal to 45 degrees, the switching tubes Q5 and Q2 are controlled to be conducted, current flows in from the C-phase winding, and flows out from the A-phase winding, and the conducting direction is C-A. At this time, C, A two-phase windings are excited, and the rotor generates counterclockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the stator salient poles of C, A two phases and the flux linkage reluctance is minimum.

4) As shown in fig. 7: when theta is larger than or equal to 45 degrees and smaller than or equal to 60 degrees, the switching tubes Q3 and Q2 are controlled to be conducted, current flows in from the winding of the phase B, and flows out from the winding of the phase A, and the conduction direction is B-A. At this time, B, A two-phase windings are excited, and the rotor generates counterclockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the stator salient poles of B, A two phases and the flux linkage reluctance is minimum.

5) As shown in fig. 8: when theta is larger than or equal to 60 degrees and smaller than or equal to 75 degrees, the switching tubes Q3 and Q6 are controlled to be conducted, current flows in from the winding of the phase B, and flows out from the winding of the phase C, and the conducting direction is B-C. At this time, B, C two-phase windings are excited, and the rotor generates counterclockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the stator salient poles of B, C two phases and the flux linkage reluctance is minimum.

6) As shown in fig. 9: when theta is larger than or equal to 75 degrees and smaller than or equal to 90 degrees, the switching tubes Q1 and Q6 are controlled to be conducted, current flows in from the A-phase winding, and flows out from the C-phase winding, and the conducting direction is A-C. At this time, A, C two-phase windings are excited, and the rotor generates counterclockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the stator salient poles of A, C two phases and the flux linkage reluctance is minimum.

The above steps are only one case of the control logic, and the same purpose can be achieved by adjusting the angle of the initial position according to actual application.

As shown in fig. 3: and the control program outputs a control waveform by taking a mechanical angle of 90 degrees as an electrical cycle according to the conduction control sequence, wherein the high level is on, and the low level is off, so that the corresponding switching tube is controlled to be switched on and off. The motor is operated by forming a continuous rotating reluctance torque. The control program controls the phase current through the PWM signal, and the purpose of controlling the rotating speed of the motor is achieved.

The technical effects of the present invention will be described in detail with reference to simulations.

Simulation results as shown in fig. 10, indicate an operating principle of A, B phase winding excitation: the current flows in from the A-phase winding and flows out from the B-phase winding, and the conduction direction is A-B. At this time A, B the two-phase winding is excited and the flux is always closed along the path of least reluctance. Therefore, when the salient poles of the rotor and the salient poles of the stator are not overlapped, reluctance force acts on the rotor and generates torque to lead the rotor to tend to a position with the minimum reluctance, and the rotor generates anticlockwise reluctance torque because two adjacent salient poles of the rotor are aligned with the salient poles of the stator with two phases of A, B and the reluctance of the flux linkage is minimum.

In the description of the present invention, "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

The above description is only for the purpose of illustrating the present invention and the appended claims are not to be construed as limiting the scope of the invention, which is intended to cover all modifications, equivalents and improvements that are within the spirit and scope of the invention as defined by the appended claims.