Implementation of DTC for IPMSM with FPGA considering field weakening operation

In this paper, a whole design of FPGA (Field-Programmable Gate Array) based control system for IPMSM (Interior Permanent Magnet Synchronous Motor) is presented. The IPMSM is now widespread for traction drive applications of electric vehicles (EVs) because of its high torque per volume ratio. In a DTC (Direct Torque Control) drive, flux linkage and electromagnetic torque are controlled directly and independently of each other by the selection of optimum inverter switching modes. In this contribution a DTC system is proposed to cope with efficiency optimization, limitation of the starting current and field weakening. The proposed DTC system utilizes the maximum-torque-per-flux (MTPF) method for efficiency maximization and a method for limiting the starting currents.