| 초록 |
Interior permanent-magnet (IPM) motor has been used as a traction motor because of high torque density and high efficiency. Maximum torque per ampere (MTPA) control that minimizes the motor copper loss is widely applied. However, the conventional MTPA control generates torque ripple because of the motor spatial harmonics. To reduce torque ripple, the multi-reference frame control (MRFC) was developed before. The MRFC method has very good performance in reducing torque ripple. However, the MRFC has some disadvantages that current overshoot occurs in the low motor speed. Moreover, reducing torque ripple at various frequencies requires many current maps and microprocessor memories. This paper proposes a novel method based on the MRFC. By suggesting a torque error map with changing the current commands from DC to AC, the current overshoots in the low speed was improved. In addition, the transient response of dq currents was improved by applying a PI controller based on complex vector(CV). The proposed method is verified through computer simulations and experimental results with 45 kW IPM motor embedded in Santa Fe hybrid electric vehicle (HEV) drive system. |
