傅里叶变换的行波型中空超声电机的系统效率

Study of the System Efficiency of the Traveling Wave and Hollow Type Ultrasonic Motor Based on Fourier Transform

由于行波型中空超声电机的驱动信号为高压、高频信号,因此,由行波型中空超声电机及其驱动器组成的系统的各级功率与效率不容易获取,这些因素均影响到后续对行波型中空超声电机性能的研究。针对此问题,首先,通过傅里叶变换的方法对超声电机驱动信号进行处理,构建了电机及其驱动系统各级效率的计算方法;然后,通过实验获取了行波型中空超声电机及其驱动器组成的系统的效率,并进一步研究了驱动频率、驱动电压及谐振匹配点对系统效率的影响。实验表明:驱动频率越靠近谐振频率,系统总效率越高;驱动电压越大,系统总效率越高;驱动电路匹配的谐振点远远高于电机机械谐振频率,使得驱动信号频率介于电路谐振频率和机械谐振频率之间时系统的效率最高。

The traveling wave type ultrasonic motor has a high-pressure and high-frequency drive signal.The power and efficiency are difficult to detect at all levels of the system,which affects subsequent study of the performance of the traveling wave and hollow type ultrasonic motor.First,the ultrasonic motor drive signal is processed using the Fourier transform method.Then,the calculation method of all efficiency levels of the motor and drive system is established,and the power and efficiency are detected.Further,the effects of the driving frequency,driving voltage and resonance matching points on the system′s efficiency are studied.Experiments show that the closer the resonance frequency of the driving frequency and the larger the drive voltage,the higher the overall efficiency of the system.Experiments ensured that the resonance point of the driver circuit was much higher than the mechanical resonant frequency,so that the drive signal frequency lay between the circuit resonance frequency and the mechanical resonant frequency.In this case,the efficiency of the system was highest.