Research On Sinusoidal-wave Control Of Brushless DC Motor Based On Sector Time Tracing Algorithm

BLDCM have such advantages as simple structure, decent speed-regulating performance and easy mantenance, etc, which ensures its wide use in such fields as electric vehicle, household appliances, aeronautics and astronautics, etc. Along with gradually increasing requirement on the motor torque pulsation and the restriction on the operating noise, the sine wave control strategy based on SVPWM is gradually applied to the brushless DC motor control system. For sine wave control on the BLDCM with hall sensors, as the limited number of installed hall sensors do not have very high spatial resolution and could not accurately reflect the real-time position of the rotor. Therefore, it is necessary to study the technology estimating the position of the rotor of the BLDCM to improve the motor’s operating characteri stics.To address the shortages of rotor position estimation methods such as zero-order estimation and six-step averaging method, this paper proposes a rotor position estimation method based on sector time tracing algorithm. Using several previous hall sector times and combining correlation analysis, this method makes judgment on the accelerating and decelerating status of the motor and then uses sector time compensating method to obtain the estimated value of current sector time and further calculate the rotor’s rotating speed and positions. The simulation result shows that, compared to zero-order estimation and six-step averaging methods, the method this paper proposes could well consider the anti-interference capability of rotor position estimation and the rapidness of rotor position tracing and could provide quite accurate rotor position information for SVPWM control, presenting decent values for practical engineering. On this basis, the proposed method is applied to the study on and development of sine wave controller of BLDCM of electric vehicle to facilitate the presentation of the design scheme of controller of electric vehicle using STM32F103 as the main control chip. The corresponding prototype model is developed with experimental verification. Relevant results show that, by introducing the rotor position estimation method based on sector time tracing algorithm, the electric vehicle controller this paper designs could operate stably with decent performance to satisfy the need of motor control in electric vehicle.