A method for operating at least two pulse-width-modulated inverters connected to a direct-current supply network. The pulse-width-modulated inverters are each actuated via an actuation signal and operated in an operating point. A phase difference is generated between the actuation signals of the at least two pulse-width-modulated inverters by adapting the actuation signal of at least one of the pulse-width-modulated inverters as a function of operating point information describing the operating points of the pulse-width-modulated inverters.

A power conversion system includes an inverter and a controller configured to: responsive to startup of the system, measure a motor speed of the IPM motor; responsive to the motor speed being less than a threshold, generate the inverter switching control signals to perform high frequency injection (HFI); during the HFI, determine a measured angle of the IPM motor; during the HFI, generate the inverter switching control signals to provide an injected current to the IPM motor; detect acceleration or deceleration of the IPM motor responsive to the injected current; selectively determine an electrical angle as half the measured angle or as 180 degrees plus half the measured angle based on the detected acceleration or deceleration of the IPM motor; and responsive to determining the electrical angle, generate the inverter switching control signals to drive the IPM motor to a reference frequency in a normal operating mode of the inverter.

The present disclosure an include an electrical assembly comprising a power converter having an AC side and a DC side, the AC side for connection to an AC network; at least one power transmission medium connected to the DC side of the power converter; a dynamic braking system operably connected to the or each power transmission medium, the dynamic braking system including a dynamic braking control unit programmed to selectively control activation of the dynamic braking system to carry out a dynamic braking operation; a monitoring unit for monitoring an electrical parameter of the AC network; and a processing unit programmed to determine an operating state of the AC network from the monitored electrical parameter, wherein the dynamic braking control unit is programmed to be responsive to the determined operating state of the AC network by configuring the dynamic braking system to be activatable.

According to the integrated power conversion apparatus and method according to the exemplary embodiment of the present disclosure, the on-board battery charger (OBC), the lower voltage battery charger (LDC), and the traction converter (TC) are integrated to convert the power so that all the functions which need to be performed by the power conversion system of the related art can be performed. Further, the number of switches is reduced to increase a power density and not only the number of switches, but also the number of controllers is reduced to improve feasibility.

An exemplary renewable-energy system including a back end system coupled to an isolated DC power source and a generator powered by a renewable energy source and including first circuitry configured to convert first AC power from the generator to DC power and to provide the DC power to a DC power bus, the first circuitry further configured to initiate operation using power from the isolated DC power source. The example system further includes a front end system comprising an inverter coupled to an isolated DC power source generator. The inverter includes a ground isolation monitor interrupter (IMI) circuit coupled to the DC power bus and configured to receive the DC power and convert the DC power to second AC power for provision to a power grid. The isolated power source generator ground-isolates third AC power of the power grid for conversion to DC power for the isolated DC power source.

In an embodiment, a power module may include: a plurality of first stages, each having an H-bridge to receive an incoming AC voltage at a first frequency and rectify the incoming AC voltage to a DC voltage; a plurality of DC buses, each to receive the DC voltage from one of the plurality of first stages; a plurality of second stages, each coupled to one of the plurality of DC buses to receive the DC voltage and output a second AC voltage at a second frequency; and a hardware configuration system having fixed components and optional components to provide different configurations for the power module.

This power conversion device has: a main breaker and a main electromagnetic contactor connected to a main power supply; a converter body having a switching element; a power supply-side reactor and a device body-side reactor connected to the main electromagnetic contactor; a current detector; a smoothing capacitor; a DC voltage detector that detects a voltage of the smoothing capacitor; a control unit; and accessories. The accessories have: a power-supply phase detection transformer that detects the phase and the amplitude of a power supply voltage; a current limiting resistor that suppresses rush current to the smoothing capacitor at an initial turning-on stage of the main power supply; an electromagnetic contactor which is for turning on current limiting operation and which connects the current limiting resistor and the main power supply; and a filter circuit that removes current ripples caused by switching of the switching element. The main breaker, the main electromagnetic contactor, and an input terminal of the power-supply phase detection transformer in the accessories are connected to one another. The power supply-side reactor, the device body-side reactor, and a filter terminal in the accessories are connected to one another.

A continuous time digital signal processing (CT DSP) token includes a first signal indicating a change has occurred and a second signal indicating a direction of the change. An amplitude generation circuit operates to generate an amplitude value x in response to the token. A power estimation circuit processes the amplitude value x to generate a digital power signal in accordance with the formula: x.sup.2±2x+1.

One embodiment is a system comprising a medium voltage direct current (MVDC) link electrically coupling a first AC-DC converter and a second AC-DC converter. The first AC-DC converter is electrically coupled with a first alternating current (AC) feeder. The second AC-DC converter electrically coupled with a second AC feeder. A battery charger electrically coupled with the MVDC link via a converterless connection. A first electronic controller is operatively coupled with the first AC-DC converter. A second electronic controller is operatively coupled with the second AC-DC converter. During operation of the battery charger to charge a battery the first electronic controller is configured to control power flow between the first AC feeder and the second AC feeder and the second electronic controller is configured to control the voltage of the MVDC link.

There is provided a transformer system (10) for converting a grid voltage (V.sub.grid) to a regulated voltage (V.sub.regulated) and output the regulated voltage (V.sub.regulated) to a power line (30), the transformer system (10) comprising: a first transformer (40) configured to step down the grid voltage (V.sub.grid) to an unregulated voltage (V.sub.unregulated) and provide the unregulated voltage (V.sub.unregulated) at an output of the first transformer (40); a shunt coupling transformer (50) connected in parallel with the output of the first transformer (40) and further connected to power electronics circuitry (60); and a series coupling transformer (70) connected in series with the output of the first transformer (40) and further connected to the power electronics circuitry (60). The power electronics circuitry (60) adds, via the series coupling transformer, a conditioning voltage (V.sub.conditioning) in series to the unregulated voltage (V.sub.unregulated) to generate the regulated voltage (V.sub.regulated). The first transformer, the series coupling transformer and the shunt coupling transformer are housed in a single transformer tank (80), and the power electronics circuitry is housed in a power electronics enclosure (90) separate from the transformer tank. Each of the transformer tank and the power electronics enclosure comprises one or more openings (95) through which electrical connections (97) between the shunt coupling transformer (50), the series coupling transformer (70) and the power electronics circuitry (60) pass.