| 摘要 |
PCT No. PCT/SE82/00353 Sec. 371 Date Jun. 9, 1983 Sec. 102(e) Date Jun. 9, 1983 PCT Filed Oct. 26, 1982 PCT Pub. No. WO83/01694 PCT Pub. Date May 11, 1983.The power drawn by a load (RL) from an A.C. network is controlled by an operational amplifier (OP1) and a power transistor (TR2). The operational amplifier makes the transistor leading when the voltage of its inverting input which is derived from said network, is lower than a reference voltage supplied to its non-inverting input. The pulses through the load take a form corresponding to the first and last parts of a sinusoidal half-wave. Their time lengths are shortened according as the voltage of the feeding network increases, and vice versa. FIG. 1. |
