A soft-landing pwm control method and system for piezoelectric high-speed switching valves

Abstract

The invention discloses a soft landing PWM control method and system for a piezoelectric high-speed switch valve. The method comprises the steps of providing a common PWM control signal, capturing therising edge and the falling edge of the common PWM control signal, and carrying out triggering on the rising edge and generating a first power function control signal, wherein the first power function control signal controls a valve element to reach the valve element largest-opening maintenance stage with the low striking velocity at the valve element opening stage, the first power function control signal lasts on till a closing trigger point; and carrying out triggering on the falling edge and generating a second power function control signal, wherein the second power function control signalcontrols the valve element to reach the valve element largest-closing maintenance stage with the low striking velocity at the valve element closing stage, and the second power function control signallasts on till the start trigger point of the next cycle. According to the soft landing PWM control method and system for a piezoelectric high-speed switch valve, because the common PWM signals serveas the trigger sources, the soft landing characteristics can be adjusted according to the actual requirements of a user, vibration and noise reduction on the high-speed switch valve can be implemented, and the dynamic characteristics of the high-speed switch valve can be well kept as well.

Description

technical field [0001] The invention relates to the control field of piezoelectric high-speed switching valves, in particular to a soft-landing PWM control method and system for piezoelectric high-speed switching valves. Background technique [0002] As a typical digital valve, the high-speed switching valve has the advantages of anti-pollution, good repeatability, low cost and high reliability. It is widely used in the fields of vehicle braking, engine fuel adjustment and aircraft brake lights. A high-speed switching valve is usually driven by a pulse width modulation (Pulse Width Modulation, PWM) digital signal, and outputs a discretized flow rate by adjusting the duty cycle of the PWM signal. At present, high-speed switching valves on the market generally use electromagnets as their electro-mechanical converters, and their operating frequency is usually lower than 50Hz. Compared with electromagnetic high-speed switching valves, applying smart materials to high-speed swit...

AI Technical Summary

Problems solved by technology

After adopting conventional PWM signal control, the opening and closing time of the spool of the piezo-driven high-speed switching valve is generally less than 0.5ms. Speed ​​impact on the valve seat, on the one hand, causes problems such as strong vibration and high noise in the system, on the other hand, due to high-frequency impact, the material on the surface of the valve core and the valve seat is worn away, which further has a significant impact on the output flow characteristics of the high-speed switching valve

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