Software Resolver-to-Digital Converter for Compensation of Amplitude Imbalances using D-Q Transformation

Kim, Youn-Hyun;Kim, Sol

  • Received : 2013.02.07
  • Accepted : 2013.04.18
  • Published : 2013.11.01


Resolvers are transducers that are used to sense the angular position of rotational machines. The analog resolver is necessary to use resolver to digital converter. Among the RDC software method, angle tracking observer (ATO) is the most popular method. In an actual resolver-based position sensing system, amplitude imbalance dominantly distorts the estimate position information of ATO. Minority papers have reported position error compensation of resolver's output signal with amplitude imbalance. This paper proposes new ATO algorithm in order to compensate position errors caused by the amplitude imbalance. There is no need premeasured off line data. This is easy, simple, cost-effective, and able to work on line compensation. To verify feasibility of the proposed algorithm, simulation and experiments are carried out.


Resolver-to-Digital converter (RDC);Synchronous demodulation;Angle Tracking Observer (ATO);Amplitude unbalance


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