Research And Design Of The Bi-directional Driver Used In Moving Coil Type Proportional Electromagnet

With the development of modern electronic technology and modern controltheory, the hydraulic control field gets rapid development. Digital controltechnology which is gradually replace the analog control technology hasbecome the development direction of the hydraulic control technology. Inelectro-hydraulic control technology, the proportional valve driver is one of themain direction of current research. Proportional valve driver on the market atpresent is still widely used one-way proportional valve driver. This topic basedon the present situation proposes of a bi-directional driver used in moving coiltype proportional electromagnet.This paper, based on the analysis of the structural characteristics anddrive mode of moving iron proportional electromagnet and moving coilproportional electromagnet, designs the bi-directional driver used in movingcoil type proportional electromagnet on the basis of51microcontroller system,and completes the design of the drive system of hardware and software. Thehardware circuit mainly includes power circuit, flutter circuit, PWM pulse widthmodulation circuit, power amplifier circuit, current feedback circuit, A/Dconversion circuit, D/A conversion circuit, dead time delay circuit and so on. Power amplifier circuit with high frequency PWM drive mode, and the deadtime delay circuit, reduces the loss of the MOSFET power amplifier tube. ThePWM frequency and duty ratio generated by the PWM pulse width modulationcircuit are adjustable, and the duty ratio range can reach more than0%~90%.The software system design mainly includes A/D conversion module, D/Aconversion module, digital PID control algorithm and so on. The systemprogram mainly uses the modular programming ideas, and use the Cprogramming language, which is easy to modify, improve and transplantation.A large number of test show that the hardware system and software systemof the bi-directional driver used in moving coil type proportional electromagnetcan work normally, and satisfy the requirements of the stability and reliability ofthe drive system, and its output current which has the stable gain can satisfy theprecision requirement of the drive system, so the drive system has a certainpopularization valve.