An electrical converter is interconnected via a filter with an electrical load or an electrical power source. A method for controlling the converter comprises the steps of: receiving a reference flux (ψ*.sub.i) for the electrical converter; determining output signals (y) comprising currents and/or voltages measured in the filter; determining an estimated flux (ψ.sub.i) from the output signals (y); determining a corrective flux (ψ.sub.i,damp) from the output signals (y) based on a mathematical model of the filter and a quadratic cost function; determining control input signals (u) for the electrical converter based on a sum of the estimated flux (ψ.sub.i) and the corrective flux (ψ.sub.i,damp); controlling the converter with the control input signals (u); and algorithmic filtering of at least one of the output signals (y) by applying a signal filter to the at least one output signal, which is designed for amplifying the at least one output signal at a resonance frequency of the filter, whereby the corrective flux (ψ.sub.i,damp) is determined from the filtered output signals.

An integrated multi-mode, large-scale electric power support system supplies on demand at least 2,500 kW to an electrical grid with low harmonic distortion either from co-located solar or wind renewable energy DC power sources or in combination with, or alternatively, from system stored energy DC power sources via a plurality of DC-to-AC inverters with phase-shifted outputs. The power support system can also inject on demand grid power factor correcting reactive power. An alternative high voltage power support system can supply on demand at least 50 megawatts to the grid.

An object of the invention is to simultaneously solve a miniaturization and an improvement of productivity of a power conversion device, a temperature rise suppression of a smoothing capacitor, and a reduction of motor noises. The power conversion device of the invention includes a smoothing capacitor, a first power conversion unit and a second power conversion unit which are connected in parallel, and a control unit which generates a PWM pulse on the basis of an output voltage vector and a PWM carrier. The control unit includes a correction unit which corrects a predetermined output voltage vector value to two or more different output voltage vector values such that an average value in one period of the PWM carrier becomes the predetermined output voltage vector value. The correction unit corrects a first output voltage vector value in a first period, and corrects a second output voltage vector value in a second period different from the first period.

For operating multi-axis drive assemblies more reliably even in a field weakening range, a current conversion device is proposed which includes a voltage-source DC link, a plurality of inverters having each a DC input side connected to the voltage-source DC link and AC output-side terminals for connection to an electric motor, and a control device configured to short-circuit each of the inverters. A measurement device measures an electrical variable at each of the inverters. The control device determines based on the measured electrical variables independently for each of the inverters directly or indirectly whether a particular inverter is feeding energy into the voltage-source DC link, and short-circuits, when this is the case, the particular inverter independently of the other inverters. A corresponding operating method is also disclosed.

An apparatus for controlling a grid-connected inverter is disclosed. The apparatus according to an exemplary embodiment of the present disclosure is configured to promote an increase in efficiency of grid-connected inverter system and to improve a current THD by generating a voltage command by changing an offset voltage in response to size of DC-link power voltage and size of apparent power.

The present invention provides a pulse-controlled inverter comprising one or multiple semiconductor switches and freewheeling diodes arranged in parallel to each semiconductor switch. The semiconductor switches are triggered only when the current does not flow through a freewheeling diode which is arranged in parallel to the semiconductor switch. This allows the number of triggering processes for the semiconductor switch to be reduced. The reduced number of triggering processes for the semiconductor switches results in lower power losses and an increased service life of the entire system.

An electronic circuit includes: a bus bar connected to a power source having a positive terminal and a negative terminal; and a plurality of object switching elements as driving objects connected to the bus bar, the object switching elements forming a parallel connected circuit. The object switching elements include minimum on-resistance elements having minimum on-resistance compared to other object switching elements in a corresponding current region among mutually different current regions; and connection points between the minimum on-resistance elements and the bus bar are located at different locations to have mutually different inductance of respective conduction paths between the power source to the connection points located at the different locations.

An insulated gate field effect transistor (IGFET) based converter circuit is described that includes a direct current input comprising a high voltage input and a low voltage input, an IGFET gate input, and an equivalent phase leg comprising a plurality of parallel-connected cells. The parallel-connected cells each include: a first wide bandgap IGFET having a first drain electrode connected to the high voltage input, a first gate electrode connected to a first gate control input, and a first source electrode; a second wide bandgap IGFET having a second drain electrode connected to the first source electrode, a second gate electrode connected to a second gate control input, and a second source electrode connected to the low voltage input; and a step-inducing inductor coupled to: the first source electrode of the first wide bandgap IGFET, and an output node. The step-inducing inductor is connected to the output node.

A vehicle power system includes a controller configured to issue commands to open a selected set of switches of an inverter and then to operate the selected set of switches according to a pulse width modulation signal having an increasing duty cycle such that input current to a battery is driven towards zero and a magnitude of d-axis current of the drive system is reduced in response to a fault with an electric drive system.

In a power converter apparatus, a first power converter circuit is configured of first power semiconductor devices, and a second power converter circuit is connected in parallel to the first power converter circuit, and is configured of second power semiconductor devices. A control circuit generates a control signal for controlling each power semiconductor device of the first and second power converter circuits. A timing control signal generator circuit compares a first amount of current flowing through the first power semiconductor devices with a second amount of current flowing through the second power semiconductor devices, and generate a timing control signal for controlling a timing of a rise or a fail of each of the control signals inputted to the first and second power converter circuits, based on a comparison result. A timing correction circuit controls the control signals to correct the timing of the rise or the fall thereof.