A power converter including at least one piezoelectric element in a branch of a bridge of switches, the switches being controlled to alternate phases at substantially constant voltage and at substantially constant charge between the terminals of the piezoelectric element.

A power converter including: a first branch and a second branch of at least two series-connected switches each, coupled in parallel between a first terminal and a second terminal and having the junction points of their switches coupled to two terminals of application of a first voltage; a third branch and a fourth branch of at least two series-connected switches each, coupled in parallel between a third terminal and a fourth terminal, and having the junction points of their switches coupled to two terminals for supplying a second voltage; and at least one piezoelectric element coupling the first terminal to the third terminal.

A voltage sourced converter for converting power from DC to AC features a chain of power electronic modules in between which each AC connection of the converter is made so as to form a series string or arm of the modules on at least one side of that connection to the chain which are controlled so as to produce at this connection an AC voltage waveform.

A system includes a clamp circuit configured to regulate a converter input supply voltage based on control signals. The system also includes a converter configured to the adjust the converter input supply voltage to a converter output supply voltage. The system also includes a controller configured to adjust the control signals for the clamp circuit using a first mode based on the converter output supply voltage and a second mode based on the converter input supply voltage.

A circuit includes a rectifier, a charge pump, and a clamp control circuit. The rectifier has an input configured to be coupled to an alternating current (AC) power source. The rectifier rectifies an AC signal from the AC power source to produce a rectified voltage on a first voltage node. The rectifier includes a first transistor coupled to a ground node and to the input. The first switch has a first control input. The charge pump is coupled to the first voltage node. The charge pump is configured to generate a second voltage on a second voltage node. The voltage regulator is coupled to the second voltage node. The clamp control circuit is coupled to the first and second voltage nodes and has an output node coupled to the first control input.

A system includes a clamp circuit configured to regulate a converter input supply voltage based on control signals. The system also includes a converter configured to the adjust the converter input supply voltage to a converter output supply voltage. The system also includes a controller configured to adjust the control signals for the clamp circuit using a first mode based on the converter output supply voltage and a second mode based on the converter input supply voltage.

A line commutated converter (LCC) for a high voltage direct current power converter, the LCC comprising at least one LCC bridge circuit for connection to at least one terminal of a DC system, each bridge circuit comprising a plurality of arms, each associated with a respective phase of an AC system, each arm comprising: an upper thyristor valve or valves, and lower thyristor valve or valves connected in series; an associated branch extending from between the upper and lower thyristors; and at least one thyristor-based capacitor module for each phase, each module comprising a plurality of module thyristors, the or each capacitor module operable to insert a main capacitor into the respective arm of the bridge circuit by firing at least one or more of said module thyristors.

An integrated circuit for realizing a zero power consumption standby of switching power supply is disclosed, including a zero-power-consumption controller for controlling the switching power supply. The zero-power-consumption controller comprises a charge coupled circuit, a zero-power-consumption microprocessor, and a zero-power-consumption voltage regulation circuit, and an input from an AC power source is sequentially fed into the zero-power-consumption voltage regulation circuit and the zero-power-consumption microprocessor via the charge coupled circuit.

A wireless power transmission system has a wireless power receiving device that can be charged using multiple different types of wireless power transmitting devices. The different types of wireless power transmitting devices have power transmitting coils that exhibit different levels of magnetic coupling with the power receiving coil of the wireless power receiving device. The wireless power receiving device may include capacitors, resistors, and/or other loading circuits that can be independently switched into use depending on the level of magnetic coupling that is detected, on a rectified voltage level, on the size of the output load, and/or on information conveyed during handshaking operations to present a desired impedance adjustment at the power receiving coil so that data signal can be properly conveyed between the power receiving device and the power transmitting device.

A power stealing system having an electrical load, a capacitive element having an input connected to the electrical load. Some power from the electrical load may go through the capacitive element to an input of a rectifier. A voltage regulator may have an input connected to an output of the rectifier to set and control a voltage level of the electrical power from the rectifier, and provide an output of power stolen from the electrical load. An amount of power flowing through the capacitive element may be less than one percent of power flowing through the electrical load.