The Design Of Vehicle Soft Switching Power Supply Based On DSP Intelligent Control System

Soft switch inverter system of the launch vehicle is a kind of equipment whichchanges AC voltage into DC voltage. As a special power source of inverter powersource, because of the special environment and function, it is put forward that ishigher requirements of launch vehicle inverter power than traditional inverter powersupply in the volume, weight, efficiency, stability, dynamic response and reliability.The traditional inverter power supply applied directly to the launch vehicles has twoobvious problems:(1) Hard switching technology is used in inverter unit of traditionalinverter system. Hard switching technology leads to consume of power switch, andaffects the efficiency of inverter power supply.(2) MCU is used in the traditionalinverter power supply system as the control core, because of low speed. This controlmodel of power supply affects the launch vehicle to control the accuracy andefficiency of nonlinear and strong time variation load. The special environment of thelaunch vehicle causes reliability of power system by variation of temperature andelectrical surge. In order to solve the above problems, this paper introduced the softswitching technology into IGBT of the launch vehicle inverter system so that reducethe power system consume. This paper uses DSP to replace MCU, and researches onesoft switch inverter vehicle power based on intelligent control.This paper introduces the soft switch technology, DSP digital control technology,the development and application of intelligent control theory in inverter power supplyrespectively, and analyzes the working principle of soft switching full bridge DC-DCconverter. The simulation research on MATLAB soft was done, and the results showthat the soft switching inverter system can effectively reduce the switch consume.DSPIC30F6010A+CPLD is adopted in the control system as the control core. Thedouble-closed loop control system is designed, which contains outer voltage loop andinner current loop for the constant pressure control on vehicle inverter output voltage.Through simulation based on the MATLAB soft, the performances of control systemare better than the traditional inverter power, so this shows efficiency of this designscheme. This paper focuses on double-loop control system on the vehicle inverter. Thevoltage feedback loop based on fuzzy-PI compound control is as the outer loop andthe current feedback loop with current limit is as the inner loop based on P control. Anew voltage control mode on the vehicle inverter was proposed, which simulationsand experiments showed that this control mode is very good to meet optimal controlrequirements for the emission vehicle inverter power supply for nonlinear, strong timevariation load.The paper also designed the software and hardware of the vehicle power system.The hardware circuits include a minimum DSPIC30F6010A control unit, the CPLDdrive control circuit, voltage and current sampling circuit, power switch tube drivingcircuit, fault protection circuit and other hardware circuit. In the software, the controlsoftware design was realized through mixed programming on C language andassembly language based on integrated development environment provided byMicrochip Company.The experimental results show that the vehicle soft switch inverter system isbetter than the traditional inverter power supply system in switch energy consume,control accuracy and reliability, intelligent and digital control level of the vehicleinverter system have risen greatly. So it would have better application prospects.