Design Of The Main Circuit For Three-Phase Intermediate Frequency High-Voltage DC Power Supply Of ESP

The electrostatic precipitator (ESP) plays an important role in many areas, such as reduction of industrial dust emissions, reduction in air pollution, protection of ecological environment, and the protection of human health. The power supply is the most important part of ESP, the power performance determined the effect of ESP. Today, the single-phase power frequency SCR power is used commonly in industry, its performance can not meet market needs. Domestic research of high frequency switch power supply has just begun, the foreign product is expensive. The intermediate frequency power supply not only can meets the urgent needs of environmental protection, but also can be produced in large numbers within a short time, it is a good transition program of electrostatic precipitator power supply. Based on a new power supply research project of Da Lian Automatic Control Equipment Co. Ltd, a three-phase intermediate frequency high-voltage DC power supply for the ESP was studied and the main process of its development was presented.In the paper, the working principle of electrostatic precipitator and electrostatic precipitator power current development situation are introduced. Several kinds of power supplies for electrostatic precipitator in industry are compared. The important components of the three-phase intermediate frequency high-voltage DC power supply is insulated gate bipolar transistor (IGBT).The basic characteristics of IGBT are introduced. The PWM control technology is introduced. The design of the main circuit for three-phase intermediate frequency high-voltage DC power supply includes the full-bridge rectifier circuit, he voltage full-bridge IGBT inverter circuit, and the intermediate frequency transformer with full-bridge rectifier circuit. The main circuit schematic diagram and the installation process chart are completed. The specific model of diode, filter inductor, filter capacitor parameters, IGBT devices and current Hall components are identified by calculating. The work patterns of the switching device in inverter circuit are analyzed in detail. The driver circuit, buffer circuit and cooling equipment of IGBT device are designed. The over-current protection scheme is designed. The installation process of switching devices is explained. The design difficulties of the intermediate frequency transformer are introduced. According to the theoretical analysis, design and calculation, the physical devices are selected to assemble the three-phase intermediate frequency high voltage power supply prototype. The power supply prototype has enough experiments. Based on actual situation, the power supply prototype is improved. According to the experimental results, the theory of design is right, the power supply prototype has high efficiency and achieve the design requirements of the project.