Electroplate Power Supply Based On Soft Switching And Current Sharing Technology

Electroplate power supply is a major key equipment in plating industry.The requirement of the plating equipment is mainly low voltage and high current high-power DC power supply, and power is usually from a few kW to dozens of kW. Traditional electroplate power supply is used of silicon-controlled rectifier. The disadvantage of it is that large volume, low efficiency, high noise, big output ripple and slow dynamic response. Now with the development of power electronic device and control technology, switching electroplating power supply is gradually replaced traditional electroplating power supply. The marked advantage of switching electroplating power supply is high efficiency, light weight, small size and so on, which has a very broad application prospect.Switching electroplating power supply worked on high-frequency, which will cause large switching loss, thus soft switching technology is proposed. This article describes the production, principle and development of soft switching technology, analyzing several control methods of full-bridge converter, and finally pointing out the ZVS under switching tube control method in this paper. Low-voltage and high-current power output rectifier often used power diodes, which will cause large rectifier loss, however, synchronous rectification can significantly reduce the rectifier loss of the output side.In this paper, the main control chip is ISL6752.This paper design a DC power supply, whose output is 12V/100A. ISL6752 has six output pulses in total, not only to achieve full-bridge ZVS in the primary side, but also ensure the ZVS synchronous rectification in the secondary side. The application of soft switching technology and synchronous rectification can significantly improve the efficiency. Meanwhile, this paper design over-current and over temperature protection circuit.This paper also compare of several current sharing technology, choosing the maximum flow method of independent current sharing make up the parallel power module system. The paper takes the control chip UC3907 as the core of current sharing control circuit. Power supply module could parallel so that form a more powerful power supply system. By analyzing the shortcomings of conventional redundancy circuit, designing the proposed new redundancy circuit to ensure the reliability of a parallel power supply system.Finally, simulation and experimental test the correctness of systems design and control scheme.