A semiconductor device includes first and second electrodes, a semiconductor part therebetween, and a control electrode between the semiconductor part and the first electrode. The semiconductor part includes first, third and fifth layers of a first conductivity type and second and fourth layers of a second conductivity type. The second layer is provided between the first layer and the first electrode. The third layer is provided between the second layer and the first electrode. The fourth layer and the fifth layer are selectively provided between the first layer and the second electrode. In a method for controlling the semiconductor device, first to third voltages are applied in order to the control electrode while a p-n junction between the first and second layers is biased in a forward direction. The second and third voltages are greater than the first voltage, and the third voltage is less than the second voltage.

Disclosed herein are regulated power supplies. The power source delivers power to a system load and includes battery units. The power source also includes power flow devices coupled to the battery units that are configured to provide power from the battery units to the system load. Each power flow device corresponds to a respective one of the battery units, and includes a one direction current flow device connected in series with a current regulator between the respective battery unit and the system load.

A rotating electrical machine control system that controls an alternating-current rotating electrical machine having two coil sets of an N phase arranged on the same stator core includes a first inverter, a second inverter, and an inverter control device that individually controls the two inverters such that currents of different phases flow through the two coil sets. The inverter control device stops the second inverter and performs switching control of the first inverter to convert electric power between a direct current and an alternating current of an N phase, or performs switching control of the two inverters to convert electric power between a direct current and alternating currents of 2N phases. Switching devices included in the first inverter have a shorter transition time between an off state and an on state and smaller switching loss than switching devices included in the second inverter.

A control device (8) for an inverter (2) that feeds an electric machine (3), wherein the control device (8) is configured to provide pulse-width modulated switching signals (15) for driving switching elements (12) of the inverter (2), wherein the control device (8) is configured to determine a modulation type by means of which the pulse-width modulated switching signals (15) are generated depending on operating point information that describes an operating point defined by at least one operating parameter, and to use a first modulation type in at least one first operating region (21, 28, 30, 31) and a second modulation type in another operating region (32, 32a, 32b).

The invention relates to a method of controlling the on-time of a plurality of energy modules of an energy storage. The energy storage comprising a plurality of series connected energy modules forming an energy module string. A string controller is controlling which of the individual energy modules that is part of a current path through the energy module string, by control of the status of a plurality of switches. The string controller is controlling the frequency of the energy module string voltage according to an electric system reference related to a system to which the energy storage is connected. And wherein the string controller is controlling the switches of the individual energy modules so that each of the individual energy modules that are required to be included in the current path to establish the energy modules string voltage are included in the current path for at least a minimum on-time.

A short circuit protection apparatus for a power conversion apparatus supplying power to a load via a plurality of switches connected to each other in parallel includes Ma current detectors each configured to detect a sum of currents flowing through two or more switches among the plurality of switches so as to output a detection signal indicative of the sum that is detected, wherein Ma is 1 less than M, which is the number of the plurality of switches, and a short circuit determiner configured to determine, based on detection signals obtained from the respective Ma current detectors, occurrence of short circuit failure in the plurality of switches to output a cutoff instruction signal for stopping on-off drive of the plurality of switches.

A power supply includes an inverter configured to direct current (DC) power into alternating current (AC) power, an impedance matching circuit configured to supply the AC power to a load; and a controller configured to adjust disposition of a powering period, in which the AC power is output, and a freewheeling period, in which the AC power is not output, to adjust a power amount of the power supplied to the load through the impedance matching circuit by the inverter.

A power supply includes an inverter configured to direct current (DC) power into alternating current (AC) power, an impedance matching circuit configured to supply the AC power to a load; and a controller configured to adjust disposition of a powering period, in which the AC power is output, and a freewheeling period, in which the AC power is not output, to adjust a power amount of the power supplied to the load through the impedance matching circuit by the inverter.

A power conversion device and a motor system according to the present disclosure comprises an inverter circuit which is connected to a motor, a switch circuit, and a control circuit. The power conversion device and the motor system are characterized in that the inverter circuit and the switch circuit are capable of two-level operation and three-level operation, and the control circuit switches between the two-level operation and the three-level operation on the basis of the motor torque command and the rotational speed command. As a result, it is possible to reduce the total loss in the power conversion device and the motor.

A pulse width-modulated (PWM) driving method is provided for a PWM motor control system with zero-crossing compensation. The PWM driving method includes controlling each carrier generator of first, second and third PWM generators to generate a carrier offset between each of first, second and third carrier signals, at least when a current flowing in a respective phase of an alternating current (AC) motor of the PWM motor control system is between +/− 10 mA, such that a voltage between respective nodes and a reference point of respective half-bridges of the PWM motor control system are offset to obtain a variable common mode voltage each time respective PWM signals are in an off-state, at least when the respective current is crossing zero.