Research And Design Of Two Way Proportional Driver For Linear Motors

Nowadays,with the rapid development of electro-hydraulic proportional technology,control theory and electronic technology are widely used in it.The electro-hydraulic proportional control technology has become an important development and research direction.The electro-hydraulic proportional driver controls the direction and size of the output power of the electro-hydraulic proportional valve by controlling the current direction and size of the flow over the electrical to mechanical converter.Electro hydraulic proportional actuator is one of the important research directions in electro-hydraulic control.At present,two proportional electromagnets are generally used to drive the valve core to realize the two-way movement of the valve core,so the electro-hydraulic proportional drive is usually a one-way drive.This research has designed a two-way proportional driver,which can realize the bidirectional proportional drive of the linear motor.It has been studied by the single motor control in the electro-hydraulic reversing valve,which has the reference value for the development of the domestic electro-hydraulic proportional technology.After analyzing the structure characteristics and driving mode of several different types of electric mechanical converters,this paper designs a two-way proportional control driver for the moving coil linear motor.According to the design requirement of moving coil linear motor drive,the hardware circuit of the driver is designed.These include: power supply circuit module,given signal generation module,signal superposition circuit module,power amplification module and closed loop control module.The power amplifier module uses high frequency PWM signal driving mode to effectively reduce the working noise of motor and loss of power amplifier tube.According to the change of input,the duty cycle of PWM pulse width modulation signal will change accordingly.The circuit uses the pulse width modulation signal to control the direction and size of the output current of the power amplifier chip LMD18200,and the subsequent sampling current signal is fed by the feedback regulation input,thus stabilizing the output.Through simulation and experiment,it is concluded that the PWM signal can change with the input signal steadily,and the output current can drive the normal operation of the moving coil linear motor,the maximum output power can reach more than 40 W,and the output power of the ordinary drive is about 20 W,with a large output power;the hysteresis of the output force is 4%,and the output power is less than 5% to satisfy the stable output.The design requirements of the force;the driver can achieve the design requirements of bidirectional proportional control.