Mitsubishi Electric Corporation

Ryotaro Harada

Tetsuya Takahashi

Takeshi Tanaka

Masato Achihara

Mitsuhiro Takada

Kota Takagaki

A control device includes a target voltage outputter that outputs a target voltage that is a target value of output voltage of a power conversion circuit and an element controller that controls a switching element in accordance with the target voltage. Upon acquisition of an operation command that provides an instruction for startup of the power conversion circuit, the target voltage outputter raises the target voltage to a startup voltage that is below a rated voltage range of the power conversion circuit. In a case where at least one of the load devices has started up after acquisition of the operation command, the target voltage outputter raises the target voltage to an operating voltage that is greater than the startup voltage and is within the rated voltage range of the power conversion circuit.

Control device, power conversion device, and control method

A range calculator () calculates an operation value range, which is range of an operation value tor controlling a duty cycle of a chopper circuit () based on an input voltage and output voltage command value of the chopper circuit (). A chopper circuit control device () controls the duty cycle of the chopper circuit () by using an upper limit value of the operation value range when an operation value is greater than or equal to the upper limit value of the operation value range, by using the operation value when the operation value is within the operation value range, and by using a lower limit value of the operation value range when the operation value is less than or equal to the lower limit value of the operation value range.

Chopper circuit control device for controlling a duty cycle of a chopper circuit in accordance with limits of an operation value range

The resonant inverter circuit includes two or more switch elements. A detector detects an output current of the switch elements. A resonance frequency determiner determines that the resonance frequency of the resonant inverter circuit is abnormal when a number of times an absolute value of a current detected by the detector at turn-off of the switch elements is equal to or greater than a threshold is equal to or greater than a predetermined number of times that is two or more during a predetermined period that is equal to or longer than two switching periods of the switch elements. A controller causes the resonant inverter circuit to stop a switching operation when the resonance frequency determiner determines that the resonance frequency of the resonant inverter circuit is abnormal.

Power conversion device

An auxiliary power source device for a vehicle is incorporated in an electric vehicle and includes a three-phase inverter that converts an input DC voltage into a desired three-phase AC voltage and applies the three-phase AC voltage to a load. The auxiliary power source device further includes a filter reactor that is connected to respective output terminals of a three-phase inverter, a filter capacitor that is connected in a Y-shape at an end on a load side of the filter reactor and is not grounded at a neutral point, and a three-phase transformer that includes primary windings that are connected in a Y-shape at the end on the load side of the filter reactor and is grounded at a neutral point and secondary windings that are connected in a delta shape.

Auxiliary power source device for vehicle

A vehicle auxiliary power supply device includes a resonant inverter circuit that converts DC input into a desired AC voltage and outputs the AC voltage and a control unit. The control unit includes a resonance-time managing unit managing resonance time of current flowing in the resonant inverter circuit, a gate-off-command generating unit detecting overcurrent flowing in the resonant inverter circuit based on detected current of a current detector, and, when the overcurrent is detected, generating, based on detected current of the current detector and resonance time managed by the resonance-time managing unit, a gate-off command to turn off switching elements included in the resonant inverter circuit after the elapse of time after which current flowing in the switching elements becomes zero for the first time, and a gate-signal generating unit generating a gate signal that controls the switching elements to be turned off when the gate-off command is input.

Vehicle auxiliary power supply device and overcurrent protection method thereof

A power converter is installed in a casing attached beneath the floor of an electric vehicle. The power converter includes a capacitor unit and a power semiconductor module housed in a hermetically sealed part of the casing closed by a cover for closing an access port, and a cooler installed in an exposed part, the cooler cooling heat generated from the power semiconductor module. The power converter includes a bus bar that electrically connects the power semiconductor module and the capacitor unit, and a conductive bar that electrically connects the capacitor unit and the bus bar. The conductive bar is drawn from the upper surface of the capacitor unit, and is bent into a crank.

Power converter

A brake control device for an electric vehicle includes an instruction controller, a pattern generator, and comparators. The instruction controller generates an instruction signal for instructing a motor about electric brake force. The pattern generator generates a first pattern signal for changing over electric brake force to machine brake force and a second pattern signal obtained by shifting the first pattern signal by a predetermined frequency. One of the comparators outputs, as an electric-brake force pattern, smaller one of the instruction signal and the first pattern signal. The other of the comparators outputs, as a notification signal, a signal output when the second pattern signal becomes equal to or smaller than the instruction signal.

Growing community of inventors

Tokyo, Japan

Ryotaro Harada