| 摘要 |
PURPOSE:To reduce the copper loss of a phase winding by half by setting the absorption voltage of a counter-electromotive force absorbing circuit to be low voltage till counter-electromotive current flowing at the time of switching the phase winding is reduced into almost zero. CONSTITUTION:When start signal is applied, then from an over-drive signal generator 3 and a pulse train generator 1, output is generated and working is started. By the output of a distributing circuit 2, transistors TR1, TR2 are turned ON/OFF, and current is fed to phase windings L1, L2. When the transistor TR1 is turned OFF, then electromagnetic energy stored in the phase winding L1 is regenerated to a power source E1 via a diode D2, the phase windings L2, L1, a diode D3, and the transistor TR5 of a counter-electromotive force absorbing circuit 10. In this case, the transistor TR6 of an absorption voltage switching circuit 11 is turned ON, and the transistor TR5 is also ON, and so a loss is less at the transistor TR5. Besides, counter-electromotive current is to be of 1/2 of the conventional one, and so a copper loss is reduced. |
