| 摘要 |
PROBLEM TO BE SOLVED: To drive a load with no trouble by controlling the load such that an output voltage waveform or an output current waveform is set by a false pole position signal generated based on the period of a pole position detection signal in a section of a high load torque. SOLUTION: A microprocessor 18 comprises three pairs of switching transistors 12u1, 12u2, 12v1, 12v2, 12w1, 12w2 connected in series between the terminals of a DC power supply 11 to constitute an inverter wherein the voltage at the joint of each pair of switching transistors is applied to the Y-connected stator windings 13u, 13w, 13w of a DC brushless motor 13. A pole position detection signal is delivered from the output terminal of a zero-cross comparator 17 but it can not be detected accurately if the u-phase current is high and since the u-phase current is disturbed significantly, the pole position is detected based on the voltage at the neutral 13d of the stator windings 13u, 13v, 13w and the voltage at the neutral of Y-connected resistors 14u, 14v, 14w. According to the method, a load can be driven surely. |
