| Abstract |
An improvement of characteristics for a small size and hand-held type, Brushless DC Motor (BLM) with a permanent magnet rotor, which is controlled in constant speed over a wide rotative speed range, is studied in this paper. The optimal feedback control is applied to the BLM to construct a control system with robustness. A control method adopting variable gain to the compensating element to construct the control system which has excellent transient responses at each reference speed is proposed. To construct the variable compansating gain control, the weight on the optimal feedback control is examined and the relation between the weight and a transient response is clarified. The weight of each reference speed is determined by using their relationship. The optimal feedback gain of each reference speed is calculated from the characteristics of weight versus speed. It is cleared that the analytical and numerical results of the BLM system applying optimal feedback control with variable gain show the characteristics of excellent transient response over a wide operating range. Then, a Digital Signale Processor is using in the experimental circuit. The good characteristics of the BLM system is confirmed by the experiment results. |
