Speed estimation with sliding mode model reference adaptive system for PM generator in direct drive wind conversion system

This paper presents a sliding mode model reference adaptive system (SM-MRAS) to estimate the speed of permanent magnet generator (PMG) in direct drive wind conversion system (DDWCS). Compared with the speed sensor system, the DDWCS with a SM-MRAS features higher reliability. Using the proposed SM-MRAS, a speed sensorless DDWCS is developed, in which the maximum power extraction (MPE) of wind power is realized through a back-to-back controllable full power converter by using SVPWM control method. The simulation and experiment of a speed sensorless DDWCS with a 750W PMG are carried out to verify the correctness and effectiveness of the proposed SM-MRAS.