A simple multifunctional converter for small power semi-self-excited switched reluctance motor

Abstract

Disclosed is a simple multifunctional converter of a low-power half-self-excitation switch reluctance motor. The simple multifunctional converter consists of a capacitor, a storage battery and phase winding current conversion main circuits of corresponding phase winding number; the phase winding current conversion main circuits are connected in parallel; the capacitor and the storage battery are connected in series and then connected with each phase winding current conversion main circuit in parallel; through an effect of switching tubes, the power generation voltage, namely the end electric energy of the capacitor, in the exciting stage can be participated in excitation, so that the excitation voltage is flexible and controllable, and power transformation and power generation voltage adopts the same measure; the simple multifunctional converter is flexible and controlled used as a generator, and adopts the same control mode when used as a motor; and therefore, the whole simple multifunctional converter is simple in structure, simple and convenient to control, capable of realizing multiple functions which cannot be realized by the conventional asymmetrical half bridge type converter, and suitable for an integrated current conversion system of various low-power switch reluctance generators / motors.

Description

Technical field [0001] The invention relates to the field of switched reluctance motors, in particular to a simple but multifunctional switch reluctance motor converter with a low-power semi-self-excited structure and a control method thereof. Background technique [0002] The switched reluctance motor has a simple and firm structure, low manufacturing cost, no windings on the rotor, no permanent magnets, and high reliability. The failure of one phase winding does not affect the normal operation of the other phase windings. It has strong fault tolerance and has broad application prospects. [0003] When the switched reluctance motor is used as a wind generator, it has the advantages of low cost and high reliability compared with doubly-fed asynchronous or permanent magnet synchronous wind generators. When used as motors or ordinary generators in various industries, its excellent body structure And operating characteristics, it also has considerable advantages. [0004] A switched re...

AI Technical Summary

Problems solved by technology

[0006] When the switched reluctance generator is running, the existing converter system, in the excitation stage, most of the excitation power supply realizes the self-excitation mode, so that there is no need for manual work of frequent battery replacement or charging in the separate excitation mode, especially in the field of wind power, but many new The structure and control of the self-excited power supply are relatively complicated, and a special controller is required; although the traditional external excitation mode has obvious disadvantages, such as manual maintenance, charging or battery replacement, if the disadvantages can be overcome, or the time of manual participation can be extended. Frequency, and can take advantage of the stable excitation power supply of the separate excitation mode, which is also helpful for reducing torque ripple, and it is also a good mode

[0007] The most typical converter main circuit of the current switched reluctance motor is an asymmetrical half-bridge structure, which has obvious advantages and is widely used in the industry. Poor controllability and insufficient flexibility. If you want to obtain flexible and controllable excitation voltage or strengthen the voltage effect, and change the power generation voltage and other functions, the industry often uses an external circuit on the basis of an asymmetrical half-bridge structure to improve its controllability. Flexibility, but it will inevitably increase the structure, volume, cost, loss, etc.; and it is often accompanied by the increase of magnetic isolation links, which greatly increases the volume weight and cost loss of the converter system.

[0008] At present, quite a lot of new inverter main circuits can not adapt to the situation where more than one phase windings work at the same time, and considering the overall efficiency of the motor, in fact, the magnetic pole overlap coefficient of most of the existing switched reluctance motors is low. is greater than zero, that is to say, when working according to the rotor position information standard, there must be more than one phase winding working conditions at the same time, especially for switched reluctance motors greater than or equal to four-phase windings, multi-phase windings work at the same time, For example, when one phase is excited and the other phase generates power, etc., this point must be taken into account in the design of the converter, which is of great practical significance

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