| 摘要 |
PURPOSE:To obtain a noise-resistant highly reliable commutation margin angle control means by sensing the commutation margin angle of the commutatorless motor in a digital value and controlling the commutation margin angle by digital feedback. CONSTITUTION:The output of a voltage converter 71 which converts the interphase voltage sensing signal of the motor 3, the output of current converter 72 which converts the current sensing signal from a current transformer 6 into a logic signal, and the output of a digital operation unit 10 are subjected to the logical operation in an operation circuit 76 via filter-waveshaping circuits 73-75. The pulses from a pulse oscillator 5 are counted in the operation circuit 76. The difference between the output signal from a commutation margin angle digital sensor 7 comprising above mentioned circuits and the signal from a commutation margin angle setting unit 8 via an A/D converter 9 is obtained. A digital operation unit 10, to which said difference and the outputs of a position sensor 4 and the pulse oscillator 5 are inputted, controls the firing angle of a cycloconverter 2 by digital operation. |
