Fuji Electric Co., Ltd.

Osamu Takei

Hirokazu Tajima

Hiroji Nishida

Masakazu Gekinozu

Akio Toba

Yasuaki Hachisu

A high-speed charger with a long lifespan such that a power converting inverter can be reliably stopped in accordance with a forced stop signal, without causing a malfunction. Pulse transformers corresponding respectively to switching elements configure an inverter. A control circuit outputs gate signals for switching on and off the switching elements to primary side circuits, each of which includes a primary winding of one of the pulse transformers. Gate drive circuits switch on and off of the switching elements based on voltage generated in secondary windings of the pulse transformers. Transistors acting as interruption control switching elements are interposed in the primary side circuit of each of the pulse transformers. The transistors are cut off in accordance with a forced stop signal, whereby an operation of the inverter stops.

Charger with inverter and inverter gate drive circuit

A charger with a power converting inverter that can be reliably stopped by a forced stop signal, without causing an increase in part quantity. A control power supply supplies voltage to gate drive circuits, which supply gate signals to an inverter. The control power supply includes a transformer, a power supply control circuit IC that repeatedly opens and closes a primary side circuit formed by a primary winding of the transformer and an auxiliary machine power supply being connected in series, and a rectifier that generates power supply voltage to be supplied to the gate drive circuits by rectifying AC voltage generated in a secondary winding of the transformer. The power supply control IC turns off a FET in accordance with a forced stop signal, thereby forcibly switching the primary side circuit to an open state, and stopping the supply of power supply voltage to the gate drive circuits.

Charger

A charger, in one possible configuration, has an AC/DC converter that converts alternating current power supplied from an external alternating current power supply into direct current power and outputs the direct current power, a DC/DC converter that transforms the direct current power output by the AC/DC converter and supplies the transformed direct current power to a vehicle-mounted battery, and a safety control unit that forcibly stops the DC/DC converter with detection of an occurrence of a fault during charging of the vehicle-mounted battery as a trigger, and subsequently causes the AC/DC converter to stop normally.

First and second detectors and first and second forced stop circuits are included in a charger including an AC/DC converter having a PFC circuit that converts AC power supplied from an external AC power supply into DC power and a smoothing capacitor, and a DC/DC converter that transforms power output by the AC/DC converter and supplies the transformed power to a vehicle-mounted battery. The first and second detectors detect voltage applied to the vehicle-mounted battery. The first forced stopper determines whether or not voltage detected by the first detector exceeds a predetermined threshold, and causes the DC/DC converter to stop when the predetermined threshold is exceeded. The second forced stopper determines whether or not voltage detected by the second detector exceeds the threshold, and causes the DC/DC converter to stop when the threshold is exceeded.

Growing community of inventors

Hino, Japan

Osamu Takei