| Summary: | 碩士 === 國立臺北科技大學 === 電機工程系 === 107 === The main objective of this thesis is to develop the high-bandwidth servo drives. In the servo drives, the current loop bandwidth is limited by the delay time of current loop, and the bandwidth will decrease as the delay time increase. The speed loop bandwidth is limited by the delay time, which is caused by the computation time of speed loop and the current loop delay time. The position loop bandwidth is limited by the delay time, which is caused by the computation time of position loop and the inner loop delay time. In the application of serve drives, the precision and robustness of motor current is more important. As a result, delta-sigma modulator is widely used for research. In order to obtain motor current from delta-sigma modulator, Sinc filter is added to demodulate the current signal. However, Sinc filter will induce time delay in the current control loop and the current bandwidth is limited.
The thesis uses the current observer and speed observer to compensate the delay of servo drives and increase the bandwidth of servo control loop. The experimental system includes the digital signal processer TI DSP TMS320F28377D and FPGA Xilinx Inc. Artix®-7 XC7A35T. As switching frequency is 30 kHz. The bandwidth improvement results of servo drives are shown in time domain and frequency domain. The bandwidth of current control loop is improved from 3450 Hz to 5670 Hz, the bandwidth of speed control loop is improved from 308 Hz to 1340 Hz, and the bandwidth of position control loop is improved from 64.6 Hz to 420 Hz.
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