Abstract:An air compensation valve (ACV) based on the piezoelectric bimorph has been introduced in this paper. The piezoelectric ACV is installed in the idle compensation channel of the motorcycle carburetor. Through the on site collection of sensor signal and the control strategy, the ACV is driven by the pulse width modulation (PWM) control by making use of the flow characteristic of piezoelectric valve, thus the emission standard has been up to China stage III. By analyzing the inverse piezoelectric effect and the piezoelectric equations theoretically, the actual displacement and torque of the piezoelectric ACV has been obtained based on the actual size of the bimorph. The testing results showed that the piezoelectric ACV had good stability and consistency on the condition of being driven by 100 V, 15 Hz PWM control waveform. It has satisfied the requirements for the intelligent idle air compensation of the electronic carburetor.