The invention relates to the field of dimming and speed regulation related to illumination, motors and electronics, in particular to a motor-driven circuit for dimming or speed regulation control which is suitable for illumination of a silicon-controlled dimmer or adjustment of a silicon-controlled speed regulator and a control method. A detection compensation circuit for maintaining the normal work of the silicon-controlled dimmer consists of a voltage detection circuit, a current detection circuit, a follow current compensation circuit and a power factor compensation circuit; the on-off running state of the silicon-controlled dimmer or speed regulator is detected by a detection method combining output voltage change and current change of the silicon-controlled dimmer or speed regulator;the on-off and trigger running conditions of the silicon-controlled dimmer are provided by adopting a compensation method combining power factor compensation and follow current compensation; a control circuit of a load consists of a datum transformation circuit, an output duty cycle control circuit, an output current control circuit and a drive output circuit and produces a control signal by detecting mains supply AC phase-shedding operation output of the silicon-controlled dimmer or speed regulator; and the output power of the load is controlled by a load output duty cycle and load working current compound control method so as to realize large output power adjustable range of the load and high linearity of the adjusting process.