CN101534026A - Switched reluctance motor with bipolar excitation 8/6 structure sectional rotor - Google Patents

Abstract

The invention discloses a segmented rotor switched reluctance motor with bipolar excitation 8/6 structure, belonging to the field of switched reluctance motors. Its structure includes radial stator, stator winding, segmented rotor core blocks and non-magnetic rotor sleeve, among which six segmented rotor core blocks are embedded in the non-magnetic rotor sleeve to form a cylindrical rotor, radial The stator has an eight-tooth and eight-slot structure. The stator windings in the two opposite slots are a wire package, and each wire package is a phase winding, a total of four phase windings, and each phase winding passes through a four-phase H-bridge with bipolar excitation. The topology circuit is connected and current is passed through during the self-inductance rising period of each phase winding, so that one working cycle of the motor is 120°rotor position angle. The invention has small wind (oil) resistance, low iron core loss and simple structure when the motor is at high speed, and the magnetic excitation topology of the motor adopts a modularized H-bridge circuit, which saves costs.

Description

Bipolar excitation 8/6 structure segmented rotor switched reluctance motor

technical field

The invention relates to a bipolar excitation 8/6 segmented rotor switched reluctance motor, which belongs to the field of switched reluctance motors.

Background technique

There are many structural forms of switched reluctance motors, but there are mainly three commonly used structural forms, namely 6/4 structure, 8/6 structure and 12/8 structure.

The switched reluctance motor has the advantages of simple structure, firmness, low cost, reliable operation, flexible control, strong fault tolerance, and high temperature and high speed adaptability. However, the rotor of the salient pole structure of the switched reluctance motor makes the wind resistance at high speed operation large, and the resistance at high speed operation under oil cooling conditions is even greater. In order to reduce the wind (oil) resistance, the rotor slot wedge can be added or filled in the rotor. Although the effect of reducing wind (oil) resistance is obvious, it requires high technology and increases the complexity of the rotor structure. At the same time, in order to improve efficiency and reduce core loss, a short magnetic circuit structure can be used, that is, the magnetic flux passes through the adjacent stator and rotor tooth poles to close, but generally more phases or more stator and rotor poles are required, so that the motor and rotor The cost of the controller increases, and it is not suitable for high-speed operation.

At present, the 12/8 structure and 6/4 structure three-phase segmented rotor switched reluctance motors researched in the world, due to the use of stator windings distributed in full slots and a cylindrical rotor, the wind resistance of the rotor during high-speed operation is greatly reduced. , the unique short magnetic circuit characteristics make the core loss low, and the excitation topology of the above two segmented rotor switched reluctance motors is the same as that of ordinary switched reluctance motors, and can use the classic asymmetrical half-bridge unipolar excitation topology circuit . However, for the four-phase segmented rotor switched reluctance motor with 8/6 structure, due to the magnetic circuit characteristics of the segmented rotor switched reluctance motor with 8/6 structure, if an asymmetrical half-bridge unipolar excitation topology circuit is used, it will It cannot work normally, so there is no research report on the four-phase segmented rotor switched reluctance motor with 8/6 structure.

Contents of the invention

The technical problem to be solved by the present invention is to propose a bipolar excitation 8/6 segmented rotor switched reluctance motor with low wind (oil) resistance and low core loss during high-speed operation.

The segmented rotor switched reluctance motor with bipolar excitation 8/6 structure of the present invention comprises a radial stator, a stator winding, segmented rotor core blocks and a non-magnetic rotor sleeve, wherein: six segmented rotor core blocks are embedded The rotor with a cylindrical structure is formed in the non-magnetic rotor sleeve. The radial stator has an eight-tooth and eight-slot structure. The stator windings in the two opposite slots are a wire package, and each wire package is a phase winding. That is, A, B, C, and D four-phase windings, each phase winding is connected by a four-phase H-bridge topology circuit with bipolar excitation, and a positive or negative current is passed through the self-inductance rising period of each phase winding, so that the motor's A working cycle is 120°rotor position angle.

The bipolar excitation 8/6 structure segmented rotor switched reluctance motor of the present invention adopts a segmented cylindrical structure rotor assembly, which can significantly reduce the wind (oil) resistance at high speed; the adoption of a bipolar excitation scheme can make one motor The duty cycle becomes twice that of the ordinary switched reluctance motor with unipolar excitation 8/6 structure, that is, the basic frequency of the stator core flux density of the bipolar excited 8/6 structure segmented rotor switched reluctance motor is that of ordinary unipolar Half of the excitation 8/6 structure switched reluctance motor, plus the short magnetic circuit characteristics of the segmented rotor switched reluctance motor, the core loss of the bipolar excitation 8/6 structure segmented rotor switched reluctance motor is significantly reduced; The excitation topology uses a modular H-bridge circuit, which can reduce the development cycle and save costs. The entire motor has a simple structure and has broad application prospects in various drive systems. It is even more important to apply it to aerospace and naval vessels. significance.

Description of drawings

Fig. 1 is the bipolar excitation 8/6 structure segmented rotor switched reluctance motor cross-sectional schematic diagram of the present invention, and label name among the figure: 1, radial stator; 2, stator winding; 3, rotor core piece; 4, non-conductive Magnetic rotor sleeve; A, B, C, and D represent A, B, C, and D four-phase windings respectively.

Fig. 2 is the schematic diagram of the four-phase H-bridge topology circuit of the stator winding power converter of the bipolar excitation 8/6 structure segmented rotor switched reluctance motor of the present invention, and the symbol names in the figure: Us is the DC magnetic excitation power supply; C _m are capacitors; T1~T16 are power switch tubes; D1~D16 are diodes; A, B, C, and D respectively represent the connected four-phase windings of A, B, C, and D.

Fig. 3 is a schematic diagram of each phase inductance and each phase current polarity of the bipolar excitation 8/6 structure segmented rotor switched reluctance motor of the present invention.

4(a) to 4(i) are schematic diagrams of the working principle of the bipolar excitation 8/6 structure segmented rotor switched reluctance motor of the present invention.

Detailed ways

Figure 1 is a schematic cross-sectional view of a segmented rotor switched reluctance motor with bipolar excitation 8/6 structure of the present invention, including a radial stator 1, a stator winding 2, a segmented rotor core block 3 and a non-magnetic rotor sleeve 4 , wherein: six segmented rotor core blocks 3 are embedded in a non-magnetic rotor sleeve 4 to form a cylindrical rotor, the radial stator 1 has an eight-tooth and eight-slot structure, and the stator windings 2 in the opposite two slots It is a wire package, and each wire package is a phase winding, a total of four phase windings, that is, A, B, C, D four-phase windings.

The power converter of the stator winding adopts a four-phase H-bridge topology circuit structure, as shown in Figure 2, the positive and negative ends of the DC magnetic excitation power supply U _s are connected in parallel with the capacitor C _m , and each phase of the H-bridge circuit is composed of two identical bridge arms , each bridge arm is connected in series by two power switch tubes and connected to the positive and negative ends of the DC magnetic excitation power supply, and each power switch tube is connected in reverse parallel with a diode. The series points of the two power switch tubes of the first bridge arms of the first, second, third, and four-phase H-bridges are connected to the incoming terminals of the four-phase windings A, B, C, and D in turn, and the first, second, and third , the series points of the two power switch tubes of the second bridge arms of the four-phase H-bridges are sequentially connected to the outlet terminals of the four-phase windings A, B, C, and D, wherein: the first-phase H-bridge is composed of power switch tubes T1 and The first bridge arm composed of T2 and the second bridge arm composed of power switch tubes T3 and T4, the second phase H-bridge is composed of the first bridge arm composed of power switch tubes T5 and T6 and the second bridge arm composed of power switch tubes T7 and T8 The third phase H bridge is composed of the first bridge arm composed of power switch tubes T9 and T10 and the second bridge arm composed of power switch tubes T11 and T12, and the fourth phase H bridge is composed of power switch tubes T13 and T14 The first bridge arm formed and the second bridge arm formed by the power switch tubes T15 and T16 are formed.

Fig. 3 is a schematic diagram of each phase inductance and each phase current polarity of the bipolar excitation 8/6 structure segmented rotor switched reluctance motor of the present invention.

4(a) to 4(i) are schematic diagrams of the working principle of the segmented rotor switched reluctance motor with bipolar excitation 8/6 structure of the present invention. Set the motor to run counterclockwise, and define the current to be positive when the current flows from the incoming and outgoing terminals of the A, B, C, and D four-phase windings, and vice versa.

Figure 4(a) shows the initial 0° rotor position. At this time, phase A and phase B are in the rising area of their respective inductances. The winding of phase A is fed with positive current, and the winding of phase B is fed with negative current. As shown in Figure 4(a): the magnetic flux generated by the A-phase winding and the B-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. Generate suction to the motor rotor and drive the motor rotor to run counterclockwise.

Figure 4(b) shows the rotor position at 15°. At this time, phase A and phase D are in the rising area of their respective inductances. The winding of phase A is fed with forward current, and the winding of phase D is fed with forward current. The magnetic force lines generated by them are shown in the figure As shown in 4(b): the magnetic flux generated by the A-phase winding and the D-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(c) shows the position of the rotor at 30°. At this time, phase D and phase C are in the rising area of their respective inductances. The winding of phase D is fed with positive current, and the winding of phase C is fed with negative current. The magnetic force lines generated by them are shown in the figure As shown in 4(c): the magnetic flux generated by the D-phase winding and the C-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(d) shows the rotor position at 45°. At this time, phase B and phase C are in the rising area of their respective inductances. The winding of phase B is fed with positive current, and the winding of phase C is fed with negative current. The magnetic force lines generated by them are shown in the figure As shown in 4(d): the magnetic flux generated by the B-phase winding and the C-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(e) shows the rotor position at 60°. At this time, phase A and phase B are in the rising area of their respective inductances. The winding of phase B is fed with positive current, and the winding of phase A is fed with negative current. The magnetic force lines generated by them are shown in the figure 4(e): The magnetic flux generated by the A-phase winding and the B-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(f) shows the rotor position at 75°. At this time, phase A and phase D are in the rising area of their respective inductances. The winding of phase A is fed with negative current, and the winding of phase D is fed with negative current. The magnetic force lines generated by them are shown in the figure As shown in 4(f): the magnetic flux generated by the A-phase winding and the D-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(g) shows the rotor position at 90°. At this time, phase D and phase C are in the rising area of their respective inductances. The winding of phase C is fed with positive current, and the winding of phase D is fed with negative current. The magnetic force lines generated by them are shown in the figure As shown in 4(g): the magnetic flux generated by the D-phase winding and the C-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(h) shows the rotor position at 105°. At this time, phase C and phase B are in the rising area of their respective inductances. The winding of phase C is fed with positive current, and the winding of phase B is fed with negative current. The magnetic force lines generated by them are shown in the figure As shown in 4(h): the magnetic flux generated by the C-phase winding and the B-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Figure 4(i) shows the position of the rotor at 120°. At this time, phase A and phase B are in the rising area of their respective inductances. The winding of phase A is fed with positive current, and the winding of phase B is fed with negative current. The magnetic force lines generated by them are shown in the figure As shown in 4(i): the magnetic flux generated by the A-phase winding and the B-phase winding passes through the two adjacent stator teeth of the respective windings and the stator yoke in between, passes through the air gap between the stator and the rotor, and enters the rotor to form a closed loop. The motor rotor generates suction and drives the motor rotor to run counterclockwise.

Fig. 4 (a) and Fig. 4 (i) working state are identical, and Fig. 4 (a) to Fig. 4 (i) have completed a duty cycle, and promptly 120 ° of rotor mechanical position angles are bipolar excitation 8/ of the present invention A working cycle of a 6-structure segmented rotor switched reluctance motor is twice the working cycle (60°) of a common unipolar excitation 8/6 structure switched reluctance motor, so the bipolar excitation 8/6 structure is divided into The basic frequency of the stator core flux density of the segment rotor switched reluctance motor is half of that of the common unipolar excitation 8/6 structure switched reluctance motor.

According to the above method, power is circulated to each phase winding of the bipolar excitation 8/6 structure segmented rotor switched reluctance motor of the present invention, so that the motor continuously runs counterclockwise.

Claims (1)

1. A segmented rotor switched reluctance motor with bipolar excitation 8/6 structure, comprising a radial stator (1), stator windings (2), segmented rotor core blocks (3) and a non-magnetic rotor sleeve ( 4), characterized in that: the segmented rotor core blocks (3) are six segmented rotor core blocks, which are embedded in the non-magnetic rotor sleeve (4) to form a cylindrical rotor, and the radial stator (1) It is an eight-tooth and eight-slot structure. The stator windings in the two opposite slots (2) are a wire package, and each wire package is a phase winding, a total of four phase windings, and each phase winding is excited by bipolar The four-phase topological circuit is connected so that one duty cycle of the motor is 120° rotor position angle.

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