| With the continuous development of piezoelectric driven dispensing valve,its requirements for driving power are also increasing.At present,the driving power supply of piezoelectric driven dispensing valve currently researched in China generally has problems such as large volume and small adjustment range of output parameters.Therefore,it is of great theoretical significance and application value to study and design a piezoelectric driven dispensing valve driving power supply with large output power,small volume,large output voltage adjustable range and wide frequency band.The main work of this paper is as follows:(1)The working principle of the piezoelectric-driven dispensing valve is analyzed,and the realization method of the driving power system of the piezoelectric-driven dispensing valve is proposed.(2)The hardware circuit and software system in the drive power system of the piezoelectric drive dispensing valve are designed,the amplitude and frequency of the output drive pulse voltage are analyzed,and the ideal performance parameters are obtained.(3)Build an experimental platform for relevant experimental verification.According to the technical difficulties of the research,this paper solves and optimizes these key problems by using different methods when designing the hardware and software parts.(1)Small volume.Select the appropriate circuit topology and hardware circuit parameters to reduce the circuit size.(2)The output power is large.Select the appropriate boost circuit,optimize the PCB layout,and improve the heat dissipation conditions of the components,so as to improve the output power.(3)The output frequency is high.Through many experiments and optimizing the parameters of PWM control circuit,isolation drive circuit,half-bridge circuit and LC filter circuit,strictly selecting MOS tube parameters and testing waveform,the output frequency is increased.(4)Stable and good output waveform.The circuit structure is added on the hardware to improve the waveform quality,and the ADC sampling program and PID adjustment parameters are optimized on the software to stabilize the output waveform.(5)The serial port screen controls the output parameters.Mainly by writing and improving software programs,users can accurately control the output parameters of the drive power through the serial screen.Through the above research and design,a small piezoelectric-driven dispensing valve driving power supply was fabricated.Experiments show that the driving power supply has good linearity and stability and it can output a rectangular wave driving voltage signal with a frequency of1Hz-500 Hz,a voltage of 0-150 V,and a duty cycle of 40%-70%,and the waveform is good. |
