One cycle control of buck-type, current source inverter-fed, brushless DC motor drive

Traditional BLDC motor drives use voltage source inverters (VSI) that utilize PWM and hysteresis hard switching methods. It leads to generate switching losses and need to use of large heat sinks. VSIs are costly because of low reliability and need to large DC link capacitor. Moreover, common control methods such as hysteresis current control can create variable range of high frequency noises. This paper overcomes the problems of VSIs and reduces the volume and cost, by using current source inverter (CSI) which replaces an inductor instead of DC link capacitors. Also, to solve the problems of hysteresis control method, one-cycle control (OCC) technique has been used for soft switching of the inverter. Moreover, to reduce the difficulties and cost of installing electromechanical sensors in BLDC motors an appropriate method for rotor position estimation has been presented. Simulation results in Matlab/Simulink verify the effectiveness of OCC-based control of CSI-BLDC motor drive comparing to hysteresis-based VSI-BLDC motor drive.