Electromagnetic valve drive circuit design

Electromagnetic valve drive circuit design machinery plant network admin solenoid valve driver circuit design requirements drive circuit used in the process of the valve core to open the high voltage power supply, to improve the forefront of current rising rate, to speed up the opening of the valve core; With low voltage power supply full open valve core, the valve core to maintain in full open position. The high-low voltage driving circuit design difficulty is how to solve the problem of high voltage side of power tube driver. This study design of electromagnetic valve drive circuit based on IR, input channel by IRl independent low-end and high-end produce different driving voltage to achieve rapid opening and closing of electromagnetic valve. Simply issue in order to reduce the burden of the electronic control unit (ECU), MCU control fuel injection duration of square wave, IR required PWM drive pulse by programmable logic array module ( EPM) To implement. Booster circuit principle of the control system of the car battery power is generally taken from + V, and the electromagnetic valve drive circuit instantaneous power consumption particularly big, therefore, the engine starting moment exist battery voltage drop phenomenon seriously, on the one hand, cause the system not work properly, the electromagnetic valve to open or close, on the other hand, even if the electromagnetic valve can work normally, voltage on its flow characteristic is very big. Considering the system reliability, therefore, must design a set of booster circuit, the circuit during engine starting to provide enough voltage solenoid valve, solenoid valve work normally. Based on the IR driver circuit design by using the principle of booster circuit design based on the IR high voltage suspension electromagnetic valve drive circuit. To drive the two way solenoid valve as an example, based on the IR of the electromagnetic valve drive circuit principle, through CPLD PWM pulse to control the MOSFET, when the fuel injection control pulse to temporarily delay Q conduction, boosting voltage V - H by MOSFET to the solenoid valve or solenoid valve, capacitor C at the same time. Discharge, When electromagnetic valve fully open, by IR high-end produce PWM pulse wave conduction Q, provide electromagnetic valve to maintain voltage, keep the electromagnetic valve opening until the end of the injection pulse valve core, fuel injection. At this time due to the capacitor discharge, boosting voltage V - Continue to reduce the H value, the need for capacitor charging, solenoid valve and the capacitor C, via qq. ( Or Q) With the diode D ( Or I) ) A booster for capacitor charging circuit.