PWM Drive Method Considerations for Proportional Pneumo-Hydraulic Solenoid Valves.

The evolution of programmable controllers, PLCs, has allowed the digital approach to hydraulic and pneumatic applications made with proportional devices. Thus, the presence of built-in PWM (Pulse Width Modulation) blocks in most PLCs allows the direct control of the valve coils, using a simple electrical circuit to adapt the digital output of the PLC to the solenoid of the proportional device. This paper presents the calculus of the parameters for PWM drive according to the parameters of the proportional solenoid valve. An original method of increasing the native resolution of the PWM block is also presented. [ABSTRACT FROM AUTHOR]