Phase Current Reconstruction Control Strategy of Dual Three-Phase Permanent Magnet Synchronous Motor Based on Single Current Sensor

The traditional dual three-phase permanent magnet synchronous motor (DT-PMSM) phase current sampling requires at least four current sensors. However, as the quantity of sensors rises and hardware costs keep escalating, the reliability and stability of current sampling cannot be effectively guaranteed. Aiming at this problem, this article proposes a phase current reconstruction method suitable for DT-PMSM. This method calculates the current of each phase by extracting the bus current of each effective voltage vector in the sector and reconstructing it with the neutral point equation. In addition, in view of the inevitable entry of the target voltage vector into the reconstruction blind area, this article puts forward a method which involves augmenting the acting time of the forward vector and imposing vector compensation in the reverse direction, thereby enabling the target voltage vector to be driven to evade the reconstruction blind area, to achieve reliable phase current sampling. Compared with the traditional method, this method only needs to use a current sensor to realize six-phase current sampling, which minimizes the use of hardware resources and effectively guarantees the steady-state enablement and reliable operation of the sampling link. Simulation findings indicate that the proposed reconstruction algorithm has the capability to precisely acquire the current of each phase, and enable the motor to exhibit favorable steady-state and transient operational performance.