Self-adaptive excitation permanent magnet generator system

Abstract

An adaptive excitation permanent magnet generator system comprises an internal combustion engine, a permanent magnet generator and an electronic converter. The permanent magnet generator is characterized in that a rotor of the permanent magnet generator consists of a rotor I, a rotor II, a rotor hub and a torque feedback spring type regulator, wherein the rotor I is fixedly connected with the rotor hub, the rotor II and the rotor hub enable the three-point angular contact rolling combination (8) to rotate relatively flexibly, and the rotor can automatically adjust the air-gap magnetic field ofthe permanent magnet generator according to the working condition of the internal combustion engine, so that the output voltage is kept stable, and the output power is matched with the power characteristic of the internal combustion engine. Meanwhile, the permanent magnet generator system is simple and reliable, and is easy to manufacture.

Description

technical field [0001] The invention relates to an adaptive excitation permanent magnet generator system, in particular to a permanent magnet generator set used in a mobile variable frequency power supply system powered by an internal combustion engine. Background technique [0002] Due to the rapid development of power electronics technology, more and more variable frequency power supply units using permanent magnet generators are widely used in military equipment, communication base stations, vehicle power supplies, and various aspects of industry and agriculture. They have the outstanding advantages of small size and high efficiency. In order to be easy to move and not limited by climate and geographical conditions, most of these permanent magnet generator mobile power systems use small, medium and micro diesel engines or gasoline engines as power sources. The system mainly includes steam / diesel engine, generator and electronic converter. The function of a permanent magn...

AI Technical Summary

Problems solved by technology

The function of a permanent magnet generator is to convert mechanical power into electrical power, but this system using existing permanent magnet generators has limitations: because permanent magnets are used for excitation, the magnetic flux is not easy to adjust, and its characteristics are as attached image 3 As shown, the induced potential e is proportional to the speed n, the output voltage u is mainly determined by the speed n, and the output power pe increases in proportion to the square of the speed n, pe=u 2 / R; while the working characteristics of the internal combustion engine are different, such as attached figure 2 , the maximum efficiency point speed n1<the maximum power point speed n2, for example, the speed corresponding to the maximum efficiency speed is 2krpm and the speed corresponding to the maximum power point is 3krpm

If the rated voltage speed of the permanent magnet generator is designed to be the speed n1 corresponding to the highest efficiency of the internal combustion engine, the internal combustion engine speed cannot be further increased to increase the output power, because the output power of the internal combustion engine cannot keep up with the load power of the generator when the speed continues to increase; if the permanent magnet generator The rated voltage speed is designed to correspond to the speed n2 of the highest power of the internal combustion engine, and the output voltage of the generator cannot reach the rated voltage at the speed n1 with the highest efficiency; if the electronic converter is used to adjust the voltage up / down, it will undoubtedly increase the power of the converter. The current and voltage withstand value increases the cost of power components more

Otherwise, it will reduce the reliability of electrical appliances and even cause the internal combustion engine to stall

Images