A Low-Latency MTPA Control Strategy Based on Dual Virtual Signal Injection for IPMSM

Since the existence of low-pass filters (LPF) in the conventional virtual signal injection control, the system suffers from delays and inaccurate maximum-torque-per-ampere (MTPA) trajectories. To tackle the issues of dynamic response lag and MTPA trajectory deviation, this paper proposes a current vector angle determination strategy based on dual virtual signal injection (DVSI). The DVSI method superimposes two sine and cosine waves of identical frequency onto the measured current angle signal. Using the Taylor expansion and superposition principle, the proposed method cancels high-frequency components in the torque derivative to realize direct extraction of the torque derivative signal, thereby avoiding delays and errors introduced by LPF. The experiments conducted on a 3.0 kW interior permanent-magnet synchronous machine (IPMSM) drive platform validated the effectiveness of the proposed approach.