부산대학교 도서관

This paper proposes the compensation algorithm when two phase currents have the equal current scale-errors through the sensing procedure. The current scale-error causes torque ripple in the controller and inaccurate current control raises dead-time effect. The conventional algorithms have disadvantage which is not available for the equal current scale-errors in two phase currents through the sensing procedure. Specifically, with conventional algorithms, when two scale-errors are compensated by conventional algorithms, a final value comes to . The characteristic of equal scale-errors is drawn by equational analysis and integral term of d-axis current controller is used for the analysis to avoid damage of torque. Basically, the proposed algorithm implements an independent current control on two different q-axis references repeatedly. At the particular velocity, an integral value is obtained and the difference of two obtained integral values has linearity with the equal current scale-errors. In a word, the derivative of and comes to . In a result, the equal current scale-erros at two phase currents can be compensated through making converge into 0. In addition, standard values of two q-axis references and the particular velocity applied to compensator are calculated in equational analysis. Therefore the proposed compensation algorithm of equal current scale-errors helps the precise motor control with accurate current measurement. The proposed compensation algorithm in this paper is verified through experimental results.