Abstract: A control device for a power conversion device according to an embodiment includes a drive control unit outputting a control signal based on a drive quantity command value, a drive quantity adjustment unit calculating the drive quantity command value based on a torque command for the motor, an estimated value of a stator magnetic flux of the motor, and a reference value of the stator magnetic flux of the motor, a magnetic flux observer calculating the estimated value of the stator magnetic flux of the motor, and a current observer smoothing the estimated value of the stator magnetic flux on the basis of time history data of the calculated estimated value of the stator magnetic flux, and calculating an estimated value of a current flowing through a stator winding of the motor.

Abstract: A control device for a power conversion device according to an embodiment includes a drive control unit controlling a current that is caused to flow through a stator winding of a motor, a drive quantity adjustment unit calculating a drive quantity command value defining a drive quantity of the motor, a magnetic flux observer calculating calculates a first estimated value of a stator magnetic flux of the motor and a first estimated value of a rotor magnetic flux of the motor, a current observer calculating a first estimated value of the current flowing through the stator winding of the motor, and an average correction unit performing calculation on the first estimated values of the stator magnetic flux of the motor. The drive quantity adjustment unit calculates a control quantity defining the drive quantity of the motor on the basis of the first estimated values of the stator magnetic flux of the motor.

Abstract: A control device for a power conversion device according to an embodiment includes a drive control unit controlling a current that is caused to flow through a stator winding of a motor, a drive quantity adjustment unit calculating a drive quantity command value defining a drive quantity of the motor, a magnetic flux observer calculating calculates a first estimated value of a stator magnetic flux of the motor and a first estimated value of a rotor magnetic flux of the motor, a current observer calculating a first estimated value of the current flowing through the stator winding of the motor, and an average correction unit performing calculation on the first estimated values of the stator magnetic flux of the motor. The drive quantity adjustment unit calculates a control quantity defining the drive quantity of the motor on the basis of the first estimated values of the stator magnetic flux of the motor.

Abstract: A control device for a power conversion device according to an embodiment includes a drive control unit outputting a control signal based on a drive quantity command value, a drive quantity adjustment unit calculating the drive quantity command value based on a torque command for the motor, an estimated value of a stator magnetic flux of the motor, and a reference value of the stator magnetic flux of the motor, a magnetic flux observer calculating the estimated value of the stator magnetic flux of the motor, and a current observer smoothing the estimated value of the stator magnetic flux on the basis of time history data of the calculated estimated value of the stator magnetic flux, and calculating an estimated value of a current flowing through a stator winding of the motor.

Abstract: A photovoltaic system includes photovoltaic cells, inverters, a reduced electricity output state determiner which determines whether each of the photovoltaic cells is in a reduced electricity output state, a first command value generator which generates a first command value for decreasing a first power factor of a first inverter determined as in the reduced electricity output state, a second command value generator which generates a second command value for increasing a second power factor of at least one of second inverters so as to compensate for output power of the first inverter, and a controller which controls the inverters.

Abstract: A photovoltaic system includes photovoltaic cells, inverters, a reduced electricity output state determiner which determines whether each of the photovoltaic cells is in a reduced electricity output state, a first command value generator which generates a first command value for decreasing a first power factor of a first inverter determined as in the reduced electricity output state, a second command value generator which generates a second command value for increasing a second power factor of at least one of second inverters so as to compensate for output power of the first inverter, and a controller which controls the inverters.

Abstract: An inverter controller is configured to control inverters connected in parallel. The inverter controller is configured to closes switch of a first inverter and turn on a first switching element provided at the first inverter to charge capacitors of the inverters at the time of starting the inverters, and to close the other switches after the capacitors are charged.

Abstract: An inverter controller is configured to control inverters connected in parallel. The inverter controller is configured to closes switch of a first inverter and turn on a first switching element provided at the first inverter to charge capacitors of the inverters at the time of starting the inverters, and to close the other switches after the capacitors are charged.

Abstract: A system and method for starting and regulating a wound rotor motor especially during the period between inactivity and a speed determined by the voltage ratings of the drive system. In a first embodiment, a starting resistor and a starting bypass contactor are connected between the rotor of the motor and a low voltage source inverter. In an alternative embodiment, the arrangement of the first embodiment is altered by connecting a shorting contactor on one side to the junction of the voltage source inverter, the starting resistor and the starting bypass contactor so as to be short circuited on the opposite side of the shorting contactor.

Abstract: A system and method for starting and regulating a wound rotor motor (120) including a phase-controlled SCR converter (150) and a drive circuit (130, 140) having a voltage source inverter (140) and a voltage source converter (130). The SCR converter (150) regulates power transmitted to the drive circuit from the rotor of the motor (120) so that the ratings of the drive circuit are not exceeded.

Abstract: A system and method for starting and regulating a wound rotor motor (320) including a phase-controlled SCR converter (350) and a drive circuit (330, 340) having a voltage source inverter (340) and a voltage source converter (330). The SCR converter (350) regulates power transmitted to the drive circuit from the rotor of the motor so that the ratings of the drive circuit are not exceeded. A shorting contactor (390) is employed in various embodiments to increase the efficiency of the circuit.

Abstract: A power conversion system for driving a load is provided. The power conversion system comprises a power transformer having at least one primary winding circuit and at least one secondary winding circuit, the primary winding circuit being electrically connectable to an AC power source. The system further comprises at least one power cell, each of the at least one power cell having a power cell input connected to a respective one of the at least one secondary winding circuit. Each power cell also has a single phase output connectable to the load. A power switching arrangement including at least one power switch is connected to the power cell input and a DC bus, and a switch controller is connected to the power switching arrangement and the power cell input. The power cell also has a PWM output stage having a plurality of PWM switches connected to the DC bus and the single phase output. A local modulation controller is connected to the PWM output stage.