Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Shigeki Harada

Akihiko Iwata

Masaki Yamada

Shinsuke Yura

Yuuya Tanaka

Makoto Seto

Takashi Kumagai

Toshiyuki Yoshizawa

Takahiro Urakabe

Takayoshi Nagai

Kikuo Izumi

Takashi Ohsawa

Takashi Hashimoto

Yoshihiro Miyama

Ikuro Suga

Taichiro Tamida

Yusuke Higaki

Noriyuki Matsubara

Ko Sano

Kou Sano

Hiroshi Ito

Takeshi Mori

Nobuhiro Kihara

Masaya Inoue

Hiroshi Okuda

Hiroshi Araki

Kenichi Kawabata

Jun Someya

Kuniko Kojima

Moriyuki Hazeyama

Daigo Takemura

Hisanori Yamasaki

Kenji Fujiwara

Tatsuya Okuda

Masahiro Iezawa

Toshihiro Wada

Sadayuki Matsumoto

Yasuyoshi Hori

Shoji Yoshioka

Sho Shiraga

Yoshiteru Suzuki

Miyuki Takeshita

Takahiko Yamamuro

Tomoyuki Kawakami

Masao Karino

Akira Okumura

Yohei Tan

Akihiron Suzuki

Kazuya Kawabe

A drive system including: a battery; a power generation device (PGD) including a power generator (PG) mounted to an engine shaft and an inverter converting AC-voltage of the PG into DC-voltage; a drive device (DD) including a motor driving a driven component and an inverter performing bi-directional conversion between AC-voltage of the motor and DC-voltage; a switching device (SD) including a plurality of switches switching a connection of the battery and the PGD at both ends of the DD between a series connection (S-connection) and a parallel connection (P-connection) for connection; a reactor arranged between the battery and SD or between the PGD and the DD; and a controller controlling each of the SD, PGD, and DD, wherein the controller uses, when a speed of the driven component is being changed, the SD to fix the connection of the battery and PGD to S-connection or P-connection after alternately switching the connection between the S-connection and the P-connection.

Drive system and drive control method

In a drive system including a battery, a power generation device (PGD) including a generator mounted to an engine shaft, and a drive device (DD) including a motor for driving a driven component, a drive controller performs a drive control for PGD and DD and a switching control for a switching device. During a parallel connection, respective high-voltage side terminals (HVTs) of PGD and the battery are connected to a HVT of DD, and respective low-voltage side terminals (LVTs) of PGD and the battery are connected to LVT of DD. During a series connection, HVT of any one of PGD and the battery is connected to HVT of DD, and LVT of another one of PGD and the battery is connected to LVT of DD, and terminals of PGD and the battery, which are not connected to DD, are connected to each other.

A first DC/DC converter is of a constant voltage control type and is controlled so as to keep the voltage of an electric generation bus at a predetermined target value. A second DC/DC converter is of a constant current control type and is controlled so as to keep input current or output current at predetermined target current. A control circuit determines an optimum target value of electric generation bus voltage, based on different algorithms, in accordance with all or some of modes A to C which are classified by the charging/discharging condition of a second electric storage device, and controls the first DC/DC converter so that the electric generation bus voltage becomes the determined target value.

Power supply system with improved energy recovery from regenerative braking

In a power supply system using various kinds of storage batteries such as a large capacity storage battery or a small capacity storage battery, an electric power path is complicated, which may increase failures such as a short circuit trouble. There is a problem in that, when a short circuit trouble between storage batteries occurs, damage to a smaller capacity storage battery is serious. Accordingly, in a power supply system according to the present invention, the relationship among voltages, current capacities, and electric power capacities of various kinds of storage batteries such as a large capacity storage battery or a small capacity storage battery is defined so that damage to the storage batteries may be minimized even when malfunction occurs in, for example, switching a switch, and energy transfers from a higher voltage storage device.

Power supply system

An electric power supply system includes: an AC generator having a drooping characteristic; a rectification section for converting AC output of the AC generator to DC; a load having an electric storage device supplied with power from the AC generator; and a control section provided between the rectification section and the load. The control section controls the AC generator so that the AC generator operates at predetermined voltage lower than output voltage corresponding to the maximum power operation point of the AC generator.

Electric power supply system

A first DC/DC converter is provided between a rectifier for rectifying output of an electric generator driven by an engine, and a battery for supplying power to an in-vehicle load. An electric double layer capacitor and a second DC/DC converter for charge/discharge current control for the capacitor are provided between the rectifier and the first DC/DC converter. A control circuit sets a current target value which is a control target value for the second DC/DC converter, based on the voltage value of a battery bus, and when charging of the electric double layer capacitor is to be stopped based on a charge/discharge instruction signal, performs, before the charging is stopped, control of gradually attenuating the current target value for the second DC/DC converter, based on a voltage value VEDLC of the electric double layer capacitor.

Power supply system for vehicle

A switching power source for driving a light emitting element, a pulse-drive switching element connected in parallel to the light emitting element, a photodetector for detecting an intensity of an output light output from the light emitting element, a current detecting element for detecting a current flowing from the switching power source, and an operation processing unit that controls an operation of the switching power source by performing a feedback loop operation based on a detection result from the photodetector and a feedback loop operation based on a detection result from the current detecting element are provided to stabilize an emission waveform even when the light emitting element is subjected to a pulsed emission.

Light source driving device, light source driving method, and image display device

In a power conversion apparatus that boosts a solar light voltage, converts it to AC and supplies AC power to a load or system, power loss is reduced and efficiency is improved. An inverter unit, in which AC sides of three single-phase inverters receive DC power from respective sources with a voltage ratio of 1:3:9 as respective inputs are connected in series. Gradational output voltage control of an output voltage is carried out using the sum of the respective generated AC voltages. Also, a solar light voltage is boosted by a chopper circuit to generate the highest voltage DC power source. When the solar light voltage exceeds a predetermined voltage, the boosting of the chopper circuit is stopped, thereby reducing power loss due to the boosting.

Power conversion apparatus

A first DC/DC converter is connected to a higher-voltage output terminal of a rectifier by alternator wiring, a battery that supplies electric power to an on-board load is connected to the first DC/DC converter, a second DC/DC converter is connected to the higher-voltage output terminal of the rectifier by alternator wiring, and an electrical double-layer capacitor is connected to the second DC/DC converter.

Automotive electric power supply system

A highly efficient rectifier can readily replace a two-terminal diode. Its conduction losses are reduced from that of the two-terminal diode. Connected between the source and drain of a MOSFET including a parasitic diode are a micro-power converter section for boosting a conduction voltage Vds between the source and drain to a predetermined voltage, and a self-drive control section that operates based on a voltage output from the micro-power converter section. When the source and drain are conductive with each other, the micro-power converter section generates, from the conduction voltage Vds, a power source voltage for the self-drive control section, and the self-drive control section () continues drive control of the MOSFET.

Rectifier with less conduction loss than a diode

A projection display uses a light modulating device to modulate, in accordance with image data, light radiated from a light source, project the modulated light onto a screen, and display an image. The projection display separates a unit of time configuring the image data into an effective light time when the light modulating device can express the light as an image on the screen and an ineffective light time when the light modulating device cannot express the light as an image on the screen. The projection display increases the power supplied to the light source during the effective light time over the power supplied to the light source during the ineffective light time.

Projection display

In a power conversion apparatus that boosts a solar light voltage, converts it to AC and supplies AC power to a load or system, a second inverter is connected in series to one of two terminals on the AC side of a first inverter that uses, as its DC source, a DC voltage boosted from a solar light voltage by a chopper circuit. A third inverter is connected in series to the other terminal. Then, output voltages of the second and third inverters are controlled to be equal, and an output voltage is provided by using the sum of the generated voltages of the first, second, and third inverters. Thus, a mid-point potential of the DC power source is made equivalent to an intermediate potential of the output voltage of the power conversion apparatus, that is, the mid-point potential (ground potential) of a system.

A lamp lighting apparatus includes an arc spot movement detector () for monitoring an DC voltage Vb which is the bus voltage of an inverter (), and for detecting a movement of an arc spot which appears before a lampenters a state where human beings can recognize a flicker of the lamp (), and, when the arc spot movement detector () detects a movement of the arc spot, controls a switch () of a DCDC converter () so as to suppress the movement of the arc spot.

Lamp lighting apparatus

A power conversion apparatus includes a first single-phase inverter that uses as a DC power source a first DC voltage that is boosted from a solar light voltage by a boosting chopper circuit. The first single-phase inverter is arranged between two single-phase inverters that use second DC power sources that are supplied from the first DC power source. AC sides of the respective single-phase inverters are connected in series. A power conditioner thus configured provides an output voltage using the sum of the generated voltages of the respective single-phase inverters. Chopper circuits are connected between the first DC power source and the second DC power sources, and power is supplied to the second DC power sources from the first DC power source via switching devices in the single-phase inverters.

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Tokyo, Japan

Shigeki Harada