A method and device for generating a driving current of a solenoid valve

Abstract

The invention discloses a method and device for generating driving current of a solenoid valve, which are suitable for an engine fuel injection system. A high-end drive circuit is connected to one end of the solenoid valve through a sampling resistor, and a low-end drive circuit is connected to the other end of the solenoid valve. An electronic control unit Send the peak current holding control pulse signal A11 and the current feedback control pulse signal AF to the signal processing circuit, and send the low-end drive circuit control pulse signal B to the low-end drive circuit, and the signal processing circuit compares the solenoid valve drive current fed back by the sampling resistor with the reference The current corresponding to the voltage is compared, and a control signal C is sent to the high-end drive circuit. Adopting the technical scheme of the present invention can shorten the opening time of the electromagnetic valve, the hardware current feedback control circuit is simple and reliable, the adjustment frequency is high, the anti-interference effect is good during use, and the price is low, and the overall production cost is low.

Description

technical field [0001] The invention relates to the technical field of electronically controlled engine fuel injection, in particular to a method and device for generating a driving current of an electromagnetic valve. Background technique [0002] In the electronically controlled engine fuel injection system, there are very strict requirements on the opening and closing of the solenoid valve. Since the opening and closing of the solenoid valve are closely related to the driving current, it is necessary to precisely control the driving current to realize the solenoid valve action. . [0003] figure 1 Is the schematic diagram of the solenoid valve drive current waveform. like figure 1 As shown, in the engine electromagnetic bypass valve control technology, the driving current is generally required to be in the form of figure 1 The two-stage drive current shown, T1 refers to the current boost stage, T2 current peak hold stage, T3 low current hold stage, the solenoid valve ...

AI Technical Summary

Problems solved by technology

[0008] Furthermore, the reliability is not strong

In the traditional solenoid valve drive circuit, the sampling resistor is often located between the emitter of the low-end power triode and the power ground. This connection method cannot effectively suppress the interference on the power ground line, and the sampling voltage is generally less than 1V, so the sampling voltage is affected by interference. More obvious, weaker control reliability

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