CN115133682A

CN115133682A - Brushless excitation method of synchronous motor (generator)

Info

Publication number: CN115133682A
Application number: CN202210718151.5A
Authority: CN
Inventors: 范海东
Original assignee: Individual
Current assignee: Individual
Priority date: 2022-06-23
Filing date: 2022-06-23
Publication date: 2022-09-30

Abstract

The present application relates to a brushless excitation technique for a synchronous motor (generator). Brushless excitation of a synchronous motor (generator) is achieved by a simple and reliable structure. The rotor has the relative advantages of cost, performance and reliability, and can replace the rotor of a common excitation, permanent magnet and induction motor (generator) to a certain extent.

Description

Brushless excitation method of synchronous motor (generator)

Technical Field

The application relates to the technical field of motors (generators), in particular to a brushless excitation technology of a synchronous motor (generator).

Background

The motor (generator) is a device for converting electric energy into mechanical energy (converting mechanical energy into electric energy), and comprises a rotor and a stator, and is divided into three major categories, namely induction, permanent magnet and excitation according to different generation modes of a rotor magnetic field (induction generators are rare and are often used in occasions of temporarily generating electricity by induction motors). The induction motor (generator) has the advantages of simple structure and low cost, but has the defects of low efficiency, low-speed torque, low power density and the like, the permanent magnet motor (generator) has high efficiency and power density, but has the defects of high manufacturing cost, high temperature or large torque and the like, the common excitation motor (generator) generally adopts a carbon brush slip ring structure, has high efficiency and low cost, but has short maintenance period due to the existence of the carbon brush slip ring structure, is difficult to realize complete sealing, is easy to generate electric sparks, and has certain interference on radio equipment. The common brushless excitation generator adopts a mode that a rotary armature type generator is used as a special exciter and shares a rotor shaft with a rotary magnetic pole type generator to excite the latter, thereby realizing the brushless excitation of the generator.

Disclosure of Invention

The invention realizes brushless excitation of a synchronous motor (generator) by a simple and reliable structure. The rotor has the relative advantages of cost, performance and reliability, and can replace the rotor of a common excitation, permanent magnet and induction motor (generator) to a certain extent.

Disclosure of Invention

The technical problem that this application mainly solved provides a simple and reliable excitation mode, realizes the brushless excitation of excitation synchronous motor (generator).

In order to achieve the above object, the technical solution adopted by the present application is: two parallel coils are perpendicular to the rotor shaft of the motor (generator), the central line of the rotor shaft passes through the central point of the plane of the coils, one coil (called a follow-up coil) is fixed with the rotor shaft and synchronously rotates with the rotor, and the other coil is fixed relative to the shell of the motor (generator) (called an external coil). When the current in the external coil changes, no matter whether the rotor rotates or not, the changing magnetic field generated by the external coil can induce the changing current in the follow-up coil, and the changing current passes through a rectifying device (called a rotating rectifier) synchronously rotating with the rotor and then is converted into direct current to excite the rotor winding. The external coils can also be arranged in 1 pair, the follow-up coil is placed in the middle, and the rotor shaft penetrates through one of the external coils. The external coil may also be disposed directly on and as part of the housing.

Drawings

Fig. 1 is a schematic structural diagram of the present invention, wherein 1 is a rotor shaft, 2 is a rotor winding, 3 is a rotating rectifier, 4 is a follower coil, and 5 is an external coil. The external coil 5 is driven by a special circuit, generates a magnetic field required to be changed by controlling voltage, current, frequency or duty ratio loaded on the external coil, generates induced current in the follow-up coil 4, and converts the induced current into direct current for the rotor winding 2 to use through the rotary rectifier 3.

Claims

1. A brushless excitation method for synchronous motor (generator) features that the ordinary carbon brush-slip ring structure and the rotary armature type excitation generator and rotary magnetic pole type main generator used by ordinary brushless excitation generator are arranged on a shaft and excited by rotary rectifier.

2. A brushless excitation method of a synchronous motor (generator) according to claim 1, wherein the varying magnetic field is generated by an external coil arranged perpendicular to the rotor shaft and not rotating with the rotor, the rotor has a follow-up coil parallel to the external coil and rotating with the rotor, and the follow-up coil is subjected to the varying magnetic field generated by the external coil to generate a varying current, and the varying current is rectified by a rectifier mounted on the rotor, and the dc current output from the rectifier excites the rotor.

3. The intensity of the exciting magnetic field is indirectly controlled by the voltage, current, frequency, duty ratio and the like of the external coil.