Development Of Initial Position Calibration System For Resolver Tarnsformer

In order to accurately control PMSM (Permanent Magnet Synchronous Motor),the real-time detection for angle position of motor rotor precisely is necessary. As oneof several angle measurement sensor, resolver transformer has obtained widespreadapplication in servo control system with its high reliability, strong anti-interference,small size, and the advantages of simple structure. After installation, the rotor ofresolver transformer and the rotor of motor are coaxial. And in most cases, the zeropoint of motor rotor is not coincide with the resolver transformer zero point. There isan angle difference between them. This angle difference is quite important inmeasuring the rotor position of the PMSM, which is so called the Initial PositionCalibration. This paper designed an automatic system of Initial Position Calibrationfor resolver transformer in this background.Firstly, we introduce the principle and method of the Back-EMF zero-crossingdetection. The initial position can be tested through the method of judging from themoment that the PMSM rotor passes the zero position. In addition the principle andmethod of PMSM`s three phase counter electromotive force measuring are alsointroduced in this paper.Second, a PC software was designed to display the data automatically, detectfaults and print reports, which improves the system`s degree of automation and reducethe labor intensity.Finally, this subject designed the circuit and software programming, then test allthe methods in real experiment.