An Improved Phase Current Reconstruction Algorithm Using Three-Resistor Sampling Technique

In the vector control strategy of permanent magnet synchronous motors, the current closed-loop serves as the core of the dual-loop control system, and reliable, accurate current detection is a prerequisite for high-performance current loop control. To reduce costs, minimize size, and improve efficiency, this paper proposes a motor phase current reconstruction scheme based on a three-resistor current sampling method, leveraging the relationship between phase currents, DC bus current, and inverter switching states. The scheme addresses the challenges of three-phase current reconstruction by dynamically adjusting ADC sampling points and employing a space voltage vector phase-shifting method. Simulation and experimental results demonstrate the effectiveness and correctness of the proposed approach.