A winding mutual compensation structure of a coupled resonant excitation system for a brushless electrically excited synchronous motor

Abstract

The present invention proposes a brushless electric excitation synchronous motor coupled resonant excitation system winding mutual compensation structure, including a primary circuit and a secondary circuit; the primary circuit includes a first resonant compensation topology, a motor controller and a stator armature winding system; the secondary circuit includes a secondary receiving inductor, a second resonant compensation topology, a high-frequency rectifier unit and a rotor excitation winding; the first resonant compensation topology is connected to the stator armature winding system and is controlled by the motor controller; the secondary receiving inductor, the second resonant compensation topology, the high-frequency rectifier unit and the rotor excitation winding are connected in sequence. The present invention is aimed at a resonant coupled wireless excitation synchronous motor system. On the basis of reusing the stator armature winding as a transmitting inductor, the armature winding is reused again, and it is equally divided as a compensation inductor and a transmitting inductor in the resonant network topology to construct a dual-coupling system to achieve dual transmission and mutual compensation, thereby eliminating the external compensation inductor and reducing the system volume.

Description

Technical Field

[0001] The present invention relates to the fields of an excitation method for an electrically excited synchronous motor and wireless power transmission, and in particular to a winding mutual compensation structure of a coupled resonant excitation system of a brushless electrically excited synchronous motor. Background Art

[0002] In the field of drive motors for electric vehicles and other applications, permanent magnet synchronous motors (PMSMs) have seen rapid growth due to their high power density. However, they suffer from issues such as an unadjustable permanent magnet field, a limited weak magnetic field operating range, a shortage of rare earth resources, and high prices. Electromagnetic synchronous motors (EMSMs) offer greater low-speed torque, a wider high-speed constant power range, and higher efficiency, making them more suitable for the higher speed ratios and lower costs required by electric vehicles. However, a major drawback of EMS motors is the need for slip rings and carbon brushes, resulting in mechanical wear and sparks that reduce system reliability. Brushless excitation has become a technical bottleneck limiting the widespread application of these motors and remains a key scientific issue in the cutting-edge development of motor systems.

[0003] Several brushless excitation technology solutions have been proposed, including exciter-based brushless excitation, harmonic-based brushless excitation, and induction-based brushless excitation. While these approaches replace brushless motors, they often suffer from several drawbacks. For example, the exciter-based approach requires external excitation equipment, which occupies a large space. Harmonic-based approaches typically utilize third-harmonic energy for excitation, but the frequency is too close to the fundamental, resulting in magnetic field distortion and poor power factor. Induction-based approaches typically incorporate an additional winding at each stator and rotor end, limiting the excitation adjustment range and generally resulting in low efficiency. The current resonant-coupled wireless excitation method effectively overcomes these drawbacks, offering superior performance in terms of control flexibility, adjustability, and integration. This method utilizes wireless power transmission to transfer excitation energy under resonant conditions, achieving full-range regulation of the excitation current. Resonant compensation is required at the stator and rotor ends, ensuring energy is transmitted at a constant frequency to reduce harmonic content at other frequency orders, minimizing losses and improving the motor's power factor and efficiency. Since the system reuses the stator armature winding as the transmitting inductor, in order to ensure a constant transmission frequency in the primary-end resonant compensation topology, the compensation inductor and the armature winding inductance must be equal. However, the stator armature winding inductance in the motor is generally large. In addition, adding a compensation inductor will increase the volume, making it difficult to install with the motor, which is not conducive to improving the power density.

[0004] In order to solve the above problems, this patent is proposed: a brushless electric excitation synchronous motor coupled resonant excitation system winding mutual compensation structure, which divides the stator armature winding into equal sections. Each section can be used as a transmitting inductor and achieve mutual compensation. There is no need for additional compensation inductors, and there are no problems such as large size and difficulty in installation in the motor. Summary of the Invention

[0005] Based on the reuse of the stator armature winding as the transmitting inductor, the present invention proposes a winding mutual compensation structure of the coupled resonant excitation system of a brushless electric excitation synchronous motor. The center tap of the stator winding is led out and the stator winding is equally divided into two inductance sections to form a dual-coupled wireless energy transmission system. The two inductance sections serve as the transmitting inductor and the compensation inductor of each other respectively, without the need for external compensation inductors.

[0006] The present invention is achieved through the following technical solutions:

[0007] A brushless electrically excited synchronous motor coupled resonant excitation system winding mutual compensation structure:

[0008] The compensation structure includes a primary circuit and a secondary circuit;

[0009] The primary circuit includes a first resonant compensation topology, a motor controller and a stator armature winding system;

[0010] The secondary circuit includes a secondary receiving inductor L S , the second resonant compensation topology, high frequency rectification unit and rotor excitation winding;

[0011] The first resonant compensation topology is connected to the stator armature winding system, and the motor controller controls the stator armature winding system;

[0012] The secondary side receiving inductor L S , the second resonant compensation topology, the high-frequency rectification unit and the rotor excitation winding are connected in sequence.

[0013] Furthermore, the stator armature winding system includes n groups of stator armature windings;

[0014] Each of the n groups of stator armature windings has the same structure and the ends are connected to a common neutral point;

[0015] The n groups of stator armature windings are all equally divided by center taps, and the equally divided inductances are used as two sets of primary inductances of the primary circuit respectively;

[0016] The two sets of primary inductors are used as transmitting inductors and secondary receiving inductors L S Mutual inductance, and the two sets of primary inductances serve as each other's compensation inductances.

[0017] Furthermore, the stator armature winding system includes three groups of stator armature windings, namely the first group of stator armature windings L A1 and L A2 , the second set of stator armature winding L B1 and L B2 , the third group of stator armature winding L C1 and L C2 .

[0018] Furthermore, the first resonant compensation topology includes three groups of resonant compensation topology units;

[0019] The first group of resonant compensation topology units includes capacitors C A ;

[0020] The structures of the second group of resonant compensation topology units and the third group of resonant compensation topology units are the same as the structure of the first group of resonant compensation topology units;

[0021] The voltage source U s One end of the capacitor C A One end of the first set of stator armature windings L A2 One end of the

[0022] Voltage source U s The other end of the first set of stator armature winding L A1 One end of the first stator armature winding L is connected to A1 The other end of the first set of stator armature windings L A2 The other end of the capacitor C A The other end is connected.

[0023] Furthermore, the secondary side receiving inductor L S The second resonant compensation topology is connected to the high-frequency rectification unit, and the high-frequency rectification unit is connected to the rotor excitation winding.

[0024] Furthermore, when the second resonant compensation topology is an LCL-S structure;

[0025] The LCL-S structure includes a capacitor C S The high-frequency rectifier unit includes four diodes D1, D2, D3, D4 and a DC side filter capacitor C d , the rotor excitation winding includes an inductor L f and resistor R f ;

[0026] The secondary side receiving inductor L S One end of the capacitor C S One end of the capacitor C S The other end is connected to the positive electrode of diode D1 and the negative electrode of diode D3 respectively, and the negative electrode of diode D1 is connected to the negative electrode of diode D2 and capacitor C d One end and resistor R f One end of the resistor R f The other end of the inductor L f One end of the

[0027] Secondary side receiving inductor LS The other end is connected to the positive electrode of diode D2 and the negative electrode of diode D4, and the positive electrode of diode D3 is connected to the positive electrode of diode D4 and capacitor C d The other end and the inductor L f The other end is connected.

[0028] Beneficial effects of the present invention

[0029] The present invention is based on a resonant coupled wireless excitation synchronous motor system and utilizes wireless power transmission technology to achieve brushless motor excitation. The excitation energy is transferred from the stator end to the rotor end at a constant frequency. By controlling the resonant energy transmission system, the full range of excitation current can be controlled.

[0030] Based on the reuse of the stator armature winding as a transmitting inductor, the present invention leads out the center tap of the stator winding and divides the stator winding into two equal inductor sections to form a dual-coupled wireless energy transmission system. The two inductor sections serve as the transmitting inductor and the compensation inductor for each other respectively, without the need for external compensation inductors. This achieves the reuse of the stator armature winding, reduces the cost and volume investment of the resonant compensation network, and improves the integration of the system. At the same time, the parameters of the equally divided armature windings are more consistent, and the accuracy of mutual transmission compensation is higher. Energy transmission at a constant frequency can be better controlled to reduce the harmonic content of other frequency orders, reduce the loss size, and further improve the power factor and efficiency of motor operation.

[0031] The equally divided stator winding of the present invention is easy and reliable to implement in the motor. Compared with the external compensation inductor, the equally divided stator winding has higher parameter consistency, which enables the motor to more accurately perform wireless transmission of excitation energy at a constant frequency, which is beneficial to improving the power factor and efficiency. The system uses resonant wireless energy transmission to replace the brushes of traditional electrically excited synchronous motors, and can achieve full-range regulation of the excitation current. Compared with inductive and harmonic brushless excitation methods, it expands the magnetic adjustment range, improves the motor power factor and efficiency, and at the same time has a more compact structure and improved reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural diagram of the present invention;

[0033] Figure 2 This is the double-coupled resonant topology diagram in the motor;

[0034] Figure 3 This is the equivalent circuit diagram of the double-coupled resonant topology in the motor;

[0035] Figure 4 This is the topological structure diagram of the double-coupled LCL resonance in the motor;

[0036] Figure 5 This is the equivalent circuit diagram of the double-coupled LCL resonant topology in the motor;

[0037] Figure 6 This is the structural diagram of the resonant coupled wireless excitation synchronous motor system;

[0038] Figure 7 The structural diagram of the brushless excitation system of the LCL-S type double-coupled resonant synchronous motor with mutually compensated winding segments. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0040] Combine Figures 1 to 7 .

[0041] This invention, for a resonantly coupled wireless excitation synchronous motor system, reuses the stator armature winding as a transmitting inductor. This reuse further divides the armature winding into equal parts, serving as a compensation inductor and a transmitting inductor within a resonant network topology. This creates a dual-coupled system that achieves dual transmission and mutual compensation. This highly reused structure improves the overall system's power density.

[0042] A brushless electrically excited synchronous motor coupled resonant excitation system winding mutual compensation structure:

[0043] The compensation structure includes a primary circuit and a secondary circuit;

[0044] The primary circuit includes a first resonant compensation topology, a motor controller and a stator armature winding system;

[0045] The secondary circuit includes a secondary receiving inductor L S , the second resonant compensation topology, high frequency rectification unit and rotor excitation winding;

[0046] The first resonant compensation topology is connected to the stator armature winding system, and the motor controller controls the stator armature winding system;

[0047] The secondary side receiving inductor L S , the second resonant compensation topology, the high-frequency rectification unit and the rotor excitation winding are connected in sequence.

[0048] The stator armature winding system includes n groups of stator armature windings;

[0049] Each of the n groups of stator armature windings has the same structure and the ends are connected to a common neutral point;

[0050] The n groups of stator armature windings are all equally divided by center taps, and the equally divided inductances are used as two sets of primary inductances of the primary circuit respectively;

[0051] The two sets of primary inductors are used as transmitting inductors and secondary receiving inductors L S Mutual inductance, and the two sets of primary inductances serve as each other's compensation inductances.

[0052] The two primary inductors are used as transmitting inductors and secondary receiving inductors L S Mutual inductance, and the two primary inductances compensate each other to form a dual-coupled wireless energy transmission system. The corresponding structure diagram is as follows Figure 1 shown.

[0053] The stator armature winding system includes three groups of stator armature windings, namely the first group of stator armature windings L A1 and L A2 , the second set of stator armature winding L B1 and L B2 , the third group of stator armature winding L C1 and L C2 .

[0054] The primary-end LCL resonant compensation structure is selected for explanation. The double-coupled LCL resonant topology and equivalent circuit diagram of one phase of the stator three-phase winding (the other two phases are consistent with it) are shown in the figure below. Figure 2 、 3 shown.

[0055] The first resonant compensation topology includes three groups of resonant compensation topology units;

[0056] The first group of resonant compensation topology units includes capacitors C A ;

[0057] The structures of the second group of resonant compensation topology units and the third group of resonant compensation topology units are the same as the structure of the first group of resonant compensation topology units;

[0058] The voltage source U s One end of the capacitor C A One end of the first set of stator armature windings L A2 One end of the

[0059] Voltage source U s The other end of the first set of stator armature winding L A1 One end of the first stator armature winding L is connected to A1 The other end of the first set of stator armature windings L A2 The other end of the capacitor C A The other end is connected.

[0060] The secondary side receiving inductor LS The second resonant compensation topology is connected to the high-frequency rectification unit, and the high-frequency rectification unit is connected to the rotor excitation winding.

[0061] When the second resonant compensation topology is an S structure coordinated with the primary end LCL, as Figure 4 ;

[0062] The LCL-S structure includes a capacitor C S The high-frequency rectifier unit includes four diodes D1, D2, D3, D4 and a DC side filter capacitor C d , the rotor excitation winding includes an inductor L f and resistor R f ;

[0063] The secondary side receiving inductor L S One end of the capacitor C S One end of the capacitor C S The other end is connected to the positive electrode of diode D1 and the negative electrode of diode D3 respectively, and the negative electrode of diode D1 is connected to the negative electrode of diode D2 and capacitor C d One end and resistor R f One end of the resistor R f The other end of the inductor L f One end of the

[0064] Secondary side receiving inductor L S The other end is connected to the anode of diode D2 and the cathode of diode D4 respectively, and the anode of diode D3 is connected to the anode of diode D4 and the cathode of capacitor C d The other end and the inductor L f The other end is connected.

[0065] Equivalent circuit analysis such as Figure 5 , where M1 is L A1 With L S Mutual inductance, M2 is L A2 With L S The mutual inductance is ω, and the resonant frequency is ω. At this time, there are two resonant energy transfer paths in the system.

[0066] And according to different splitting methods, the stator armature winding can also be split into any reasonable number of sections, and can form various resonant networks such as LCL compensation, LCC compensation, CLC compensation, LLC compensation, etc. with the resonant capacitor. The rotor secondary end receiving winding can also form various compensation methods such as series (S) compensation, parallel (P) compensation, LCL compensation, etc. with the resonant capacitor. It can be applied to various motor structures such as salient pole motors, hidden pole motors, hybrid excitation motors, etc., which are all regarded as expanded applications of the present invention.

[0067] Taking the LCL-S compensation network as an example, its specific structure is as follows Figure 7 As shown. A1 (L B1 / L C1 ), L A2 (L B2 / L C2 ) are both L S Coupling occurs, both act as transmitting inductors and each other's compensation inductors, C A 、C B 、C C They are the resonant capacitor of the primary compensation network, C S The system only uses the equally divided armature windings (the two Ls that form the source-side LCL) to wirelessly transmit excitation energy, eliminating the need for an external compensation inductor at the stator end.

[0068] The above is a detailed introduction to the winding mutual compensation structure of the coupled resonant excitation system of the brushless electric excitation synchronous motor proposed in the present invention, and the principles and implementation methods of the present invention are explained. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for general technical personnel in this field, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A brushless electrically excited synchronous motor coupled resonant excitation system winding mutual compensation structure, characterized by: The compensation structure includes a primary circuit and a secondary circuit; The primary circuit includes a first resonant compensation topology, a motor controller and a stator armature winding system; The secondary circuit includes a secondary receiving inductor L S , the second resonant compensation topology, high frequency rectification unit and rotor excitation winding; The first resonant compensation topology is connected to the stator armature winding system, and the motor controller controls the stator armature winding system; The secondary side receiving inductor L S , a second resonant compensation topology, a high-frequency rectifier unit and a rotor excitation winding are connected in sequence; The stator armature winding system includes n groups of stator armature windings; Each of the n groups of stator armature windings has the same structure and the ends are connected to a common neutral point; The n groups of stator armature windings are all equally divided by center taps, and the equally divided inductances are used as two sets of primary inductances of the primary circuit respectively; The two sets of primary inductors are used as transmitting inductors and secondary receiving inductors L S Mutual inductance, and the two sets of primary inductances serve as each other's compensation inductances.

2. The compensation structure according to claim 1, characterized in that: The stator armature winding system includes three groups of stator armature windings, namely the first group of stator armature windings L A1 and L A2 , the second set of stator armature winding L B1 and L B2 , the third group of stator armature winding L C1 and L C2 .

3. The compensation structure according to claim 2, characterized in that: The first resonant compensation topology includes three groups of resonant compensation topology units; The first group of resonant compensation topology units includes capacitors C A ; The structures of the second group of resonant compensation topology units and the third group of resonant compensation topology units are the same as the structure of the first group of resonant compensation topology units; Voltage source U s One end of the capacitor C A One end of the first set of stator armature windings L A2 One end of the Voltage source U s The other end of the first set of stator armature winding L A1 One end of the first stator armature winding L is connected to A1 The other end of the first set of stator armature windings L A2 The other end of the capacitor C A The other end is connected.

4. The compensation structure according to claim 3, characterized in that: The secondary side receiving inductor L S The second resonant compensation topology is connected to the high-frequency rectification unit, and the high-frequency rectification unit is connected to the rotor excitation winding.

5. The compensation structure according to claim 4, characterized in that: When the second resonant compensation topology is an LCL-S structure; The LCL-S structure includes a capacitor C S The high-frequency rectifier unit includes four diodes D1, D2, D3, D4 and a DC side filter capacitor C d , the rotor excitation winding includes an inductor L f and resistor R f ; The secondary side receiving inductor L S One end of the capacitor C S One end of the capacitor C S The other end is connected to the positive electrode of diode D1 and the negative electrode of diode D3 respectively, and the negative electrode of diode D1 is connected to the negative electrode of diode D2 and capacitor C d One end and resistor R f One end of the resistor R f The other end of the inductor L f One end of the Secondary side receiving inductor L S The other end is connected to the anode of diode D2 and the cathode of diode D4 respectively, and the anode of diode D3 is connected to the anode of diode D4 and the cathode of capacitor C d The other end and the inductor L f The other end is connected.

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