A power controller circuit comprises a controller and a bi-directional switching assembly coupled to a sensor configured to sense at least one energy parameter of an energy flowing through the bi-directional switching assembly. The bi-directional switching assembly comprises a controllable switch. The controller is configured to control the controllable switch into a conduction mode during a first portion of an energy cycle of electrical energy supplied to the bi-directional switching assembly to cause the energy to flow through the bi-directional switching assembly. Via the sensor, the controller monitors the at least one energy parameter of the energy flowing through the bi-directional switching assembly. The controller controls the first controllable switch into a non-conduction mode based on an amount of the at least one energy parameter of the energy flowing through the bi-directional switching assembly during the first portion.

A power conversion device 1 includes a matrix converter circuit 10 including a plurality of switching elements and being configured to perform bidirectional power conversion between alternating current power on a primary side and alternating current power on a secondary side, a power conversion control unit 114 configured to switch on and off the plurality of switching elements in unison with a carrier wave to cause an alternating current on the secondary side to follow a control command, and a carrier wave changing unit 116 configured to change, based on a nearness level between a frequency on the primary side and a frequency on the secondary side, a frequency of the carrier wave.

A power-control device comprises an energy-import portion and an energy-export portion. The power-control device may additionally include a general processing and power supply circuit providing linear control of the power-control device's production of power to the load. The energy-import portion is coupled between a V.sub.LINE terminal and a load terminal, and is capable of importing energy to the load terminal during a first portion and a third portion of an alternating voltage V.sub.AC waveform. The energy-export portion is coupled between the load terminal and a NEU terminal, and is capable of exporting energy from the load terminal during a second portion and a fourth portion of the alternating voltage V.sub.AC waveform. The first, second, third and fourth portions of the alternating voltage V.sub.AC waveform are equal to a period of the alternating voltage V.sub.AC waveform and respectively are consecutive during the period of the alternating voltage V.sub.AC waveform. The power-control device provides variable power control to the load terminal in response to a variable on/off time of a PWM control signal.

The present invention provides a multi-load control apparatus, a slave circuit and a control method thereof. The multi-load control apparatus includes a master circuit and at least one slave circuit. The master circuit generates at least one pulse width modulation (PWM) signal according to an input signal. The slave circuit controls a power switch according to a corresponding PWM signal. The slave circuit has a primary side circuit and a secondary side circuit. The primary side circuit generates an AC PWM signal according to the corresponding PWM signal. The power switch has a control terminal which is driven according to a floating ground level which is not a constant voltage level. The power switch has a current inflow terminal and a current outflow terminal, which are connected to a corresponding load circuit in series, wherein the series circuit of the power switch and the load circuit receives an AC voltage.

A power controller circuit comprises a controller and a bi-directional switching assembly coupled to a sensor configured to sense at least one energy parameter of an energy flowing through the bi-directional switching assembly. The bi-directional switching assembly comprises a controllable switch. The controller is configured to control the controllable switch into a conduction mode during a first portion of an energy cycle of electrical energy supplied to the bi-directional switching assembly to cause the energy to flow through the bi-directional switching assembly. Via the sensor, the controller monitors the at least one energy parameter of the energy flowing through the bi-directional switching assembly. The controller controls the first controllable switch into a non-conduction mode based on an amount of the at least one energy parameter of the energy flowing through the bi-directional switching assembly during the first portion.

A power management apparatus 20 comprises a first energy harvesting input channel 21; a first energy storage element connection 25; an inductor connection 27; and a switching circuit 28. A controller 30 is configured to operate the switching circuit 28 to transfer energy between the first energy harvesting input channel 21 and the first energy storage element connection 25 by a sequence of energy transfer cycles. Each of the energy transfer cycles comprises an energise phase in which energy is transferred from the first energy harvesting input channel 21 to the inductor connection 25 for an energise time (tE) and a de-energise phase. The first energy harvesting input channel 21 is capable of receiving an AC electrical signal and a DC electrical signal. The controller 30 is configured to determine a type of an electrical signal received at the first energy harvesting input channel 21, where the type is one of an AC electrical signal and a DC electrical signal, and determine an energise time (tE) and a harvesting cycle period (tP) for the switching circuit 28 based on the determined type.

A power supply control device according to one or more embodiments may be provided to: control a power conversion device that has a configuration in which a resonant circuit is provided on an output side of a matrix converter including switching circuits having snubber elements, and that performs AC-AC conversion of output from a multi-phase AC power supply. The power supply control device performs control such that: the output current, which has a phase difference caused by the resonant circuit, is negative during a period in which an absolute value of a positive-going output voltage that is output from the power conversion device increases while the output current is positive during a period in which the absolute value of a negative-going output voltage increases; and a polarity of the output current does not change within a period in which the snubber element is discharged.

An AC-AC power converter, such as a motor soft starter, includes an input connectable to an AC source with a disconnect switch, an output connectable to an AC load, and phase lines connecting the input and output to transmit power. In-line solid-state switching blocks are connected between line terminals and load terminals of the AC source and AC load, respectively, such that each phase line includes a solid-state switching block connected thereto. Free-wheeling solid-state switching blocks are connected to the load terminals at one end and together at a common connection at another end, such that each phase line includes a free-wheeling solid-state switching block connected thereto. Each of the in-line and free-wheeling solid-state switching blocks comprises a bi-directional switching block that selectively controls current and withstands voltage in both directions. The switching blocks also provide soft-starter functions, variable speed control, and integrated circuit breaker protection capability.

A power-control device comprises an energy-import portion and an energy-export portion. The power-control device may additionally include a general processing and power supply circuit providing linear control of the power-control device's production of power to the load. The energy-import portion is coupled between a V.sub.LINE terminal and a load terminal, and is capable of importing energy to the load terminal during a first portion and a third portion of an alternating voltage V.sub.AC waveform. The energy-export portion is coupled between the load terminal and a NEU terminal, and is capable of exporting energy from the load terminal during a second portion and a fourth portion of the alternating voltage V.sub.AC waveform. The first, second, third and fourth portions of the alternating voltage V.sub.AC waveform are equal to a period of the alternating voltage V.sub.AC waveform and respectively are consecutive during the period of the alternating voltage V.sub.AC waveform. The power-control device provides variable power control to the load terminal in response to a variable on/off time of a PWM control signal.

Methods and circuits are provided for controlling an electronic switch such that it may be controlled by an external control signal, such as a PWM signal, or be set to operate in an active-diode mode, wherein current is allowed to flow through the switch in only one direction. The described circuits are configured to autonomously control the electronic switch, such that no external control signal is required when the active-diode mode is used. The provided techniques allow electronic switches to be efficiently used as part of a power stage or part of an active rectifier, so as to support bi-directional switched-mode power supplies, motor/generator drivers, and related electric circuits that require bi-directional power flow. By reusing electronic switches thusly and implementing an active-diode mode, the circuitry is minimized while maintaining good power efficiency.