The present disclosure relates to a control circuit for an electric blanket. The control circuit includes a main control circuit composed of a relatively low voltage power conversion circuit, a heating main loop, a micro control unit (MCU) main control circuit, an active/passive protection circuit and a main power carrier serial port circuit. The control circuit further includes a sub-control circuit. The sub-control circuit is composed of an auxiliary power carrier serial port circuit, a sub-control power extraction circuit, an MCU sub-control circuit, a function key input circuit and a display circuit. The main control circuit and the sub-control circuit exchange operating state information and user control information through the main power carrier serial port circuit and the auxiliary power carrier serial port circuit to implement heating control of the electric blanket in a mutually cooperative control mode.

A transformer device and a control method for the transformer device are provided. The transformer device includes a transformer, an uplink cascade connection port, a downlink cascade connection port, and a controller. The controller is enabled when the transformer receives an input electric power, and the controller determines whether the uplink cascade connection port is connected to an uplink transformer device. When the uplink cascade connection port is connected to the uplink transformer device, the controller detects a downlink external transformer device connected to the downlink cascade connection port, reports a detection result to the uplink transformer device, and obtains a control signal from the uplink cascade connection port. The controller converts the input electric power into an output electric power according to the control signal and the transformer.

A direct AC LED lighting device is provided with a low-pass filter for filtering a threshold time in which a post diode bridge voltage exceeds an LED threshold voltage during a current AC half cycle for the post diode bridge voltage.

A thyristor or triac control circuit includes a first capacitive element that is series-connected with a first diode between a first terminal and a second terminal intended to be coupled to a gate of the thyristor or triac. A second capacitive element is coupled between the second terminal and a third terminal intended to be connected to a conduction terminal of the thyristor or triac on the gate side of the thyristor or triac. A second diode is coupled between the third terminal and a node of connection of the first capacitive element and first diode.

A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

A static synchronous compensator device connected between a source and a load of a three-phase power system, comprising: a main feedback line configured to provide a main feedback signal from lines between the source and the load; a mixer configured to mix the main feedback signal with a balance function to generate a balanced signal; a signal controller configured to convert the balanced signal to a controlled signal; a gain circuit configured to multiply the controlled signal by 1 and to perform proportional gain and integral gain (P & I) processing on the controlled signal to generate an intermediate correction signal; and a pulse width modulator configured to apply a pulse width modulation pattern to modulate the voltage source inverter to generate an AC waveform that is applied to the lines between the source and the load.

The invention relates to a method and to a device for managing the operation of a lighting device (Lp) having capacitive impedance, the lighting device being supplied by an AC electric power supply network, the management device comprising means (SW1, SW2) for varying the duration of the supply of electric power to the lighting device upon each alternation of the electrical signal supplied by the AC electric power supply network, at least one resistor (R1, R2) for discharging the electric power stored by the lighting device, characterized in that the management device (10) comprises means for allowing the electric power stored in the lighting device to be discharged only when electric power is not supplied to the lighting device.

A load control device for controlling the power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting a gate current through a gate of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct the gate current through a first current path to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct the gate current through the first current path again after the firing time, but the gate current is not able to be conducted through the gate from a transition time before the end of the half-cycle until approximately the end of the half-cycle. The load current is able to be conducted through a second current path to the electrical load after the transition time until approximately the end of the half-cycle.

A power converter for heat tracing applications is disclosed. The power converter includes a controller configured to control an input switching stage. The power converter also includes an output filter, the output filter electrically coupled to the input switching stage. Further, the power converter includes a passive cooling element, the passive cooling element coupled to the power converter. The controller is configured to select a peak voltage and set a power converter output voltage based on at least one of the peak voltage and a power converter input voltage. The passive cooling element is configured to decrease a temperature of the power converter and to obviate the need for cooling with moving parts, making the system viable for hazardous areas in addition to non-hazardous areas. The input switching stage includes a plurality of transistors. The power converter output voltage and the power converter input voltage are both alternating current.

A load control device for controlling power delivered from an AC power source to an electrical load includes a thyristor, a gate coupling circuit for conducting current through a gate terminal of the thyristor, a controllable switching circuit coupled between first and second main terminals of the thyristor, and a control circuit for controlling the gate coupling circuit to conduct a pulse of current through the gate terminal to render the thyristor conductive at a firing time during a half cycle. The gate coupling circuit is able to conduct at least one other pulse of current through the gate terminal after the firing time until a transition time before an end of the half-cycle. The control circuit is configured to render the controllable switching circuit conductive to conduct current through the electrical load between approximately the transition time until approximately the end of the half-cycle.