Abstract
High performance motor control and fault diagnosis requires high resolution isolated signal measurement. Sigma-delta ADCs (SD-ADC) are ideal for this purpose but cause remarkable measurement latency which can cause performance degradation and stability issues. In this paper, the effects of current measurement latency caused by a sigma-delta filter module (SDFM) and corresponding latency compensation are discussed in detail. First, the effect of SD-ADC on system phase margin and ADC update delay is analyzed in detail. Consequently, a Kalman filter based technique is proposed to compensate the latency caused by the group delay of the digital filter and increase the phase/gain margin of the system. In addition, three PWM update strategies are proposed and their tradeoffs discussed. The proposed algorithm and measurement results are experimentally verified on a PMSM drive. It is shown that with the proposed solution, Sigma-delta ADC can provide much higher resolution than traditional SAR ADCs and also yield superior diagnostics capability and control.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.