The single current regulator can solve the problem of D-Q axis coupling in the high-speed region of the traditional voltage regulation method for magnetic weakening, and offers the benefits of simple structure and rapid dynamic response, but due to the limitation of the voltage phase angle, the bus voltage cannot be fully utilized after the motor runs into the weak magnetic area, leading to the reduction of the operation efficiency and load capacity of the motor. In this paper, a single current regulator based on voltage vector angle is proposed to control the field weakening, and the relationship between the feedforward link and torque and the D-Q axis current is identified by parameter identification, and the voltage vector angle regulator is structured to limit the D-Q axis current of the motor to the voltage-limit ellipse. Simulation results indicate that the improved SQCR-VVA can run above the voltage-limited ellipse with the d-q axis current during no-load and loading process, which has a greater voltage utilization rate than the SCR-FQV and further improves the load carrying capacity of the motor in the weak magnetic field region.