Design of Permanent Magnet Submersible Motor Driving System Based on FOC Algorithm

In this paper, a design of permanent magnet synchronous motor (PMSM) drive system based on improved field-oriented control (FOC) algorithm is proposed for the characteristics of downhole high temperature and high pressure environment. Adopting FOC as the motor control strategy. Using Sinusoidal Vector Pulse Width Modulation (SVPWM) algorithm drives inverter to generate sine wave current to drive motor rotation. The system uses a counter-electromotive force-based Sliding Mode Observer (SMO) to estimate the real-time position of the rotor and a proportional-integral (PI) tracking controller speed estimator to obtain speed estimates from the position information, which significantly reduces the cost compared to schemes using sensors. Under the same setting conditions, the response time of the improved FOC algorithm is only 0.02s.