Matsushita Electric Works, Ltd.

Panasonic Corporation

Yukihiro Murata

Nobuhiro Kitamura

Tatsuya Mukai

Yoshinori Akinari

Kenji Okada

Hiroaki Koshin

Hiroyuki Nishino

Yoshihisa Ishigami

Kouichi Teraura

Yasuhisa Ihira

Disclosed is a bidirectional DC/DC converter including: a primary side circuit that includes a first DC power source or a first load; a secondary side circuit that includes a second load or a second DC power source; and a power transfer unit that is capable of transferring power bi-directionally between the primary side circuit and the secondary side circuit. Further, the bidirectional DC/DC converter includes a control circuit that controls the primary side circuit and secondary side circuit in such a way that current flows through the power transfer unit from the first DC power source to the second load or from the second DC power source to the first load.

Bidirectional DC/DC converter with simple control operation

In an electronic switch which includes a pair of terminal portions, and self arc-suppressing elements Q, Qhaving a one-way on and off control construction connected in inverse-series between the pair of terminal portions and which turns on and off the self arc-suppressing elements Q, Qwith phase control, shunt resistors R, Rprovided between the pair of terminal portionsand connected in series to the pair of self arc-suppressing elements Q, Qand thyristors S, Sfor extracting the gate voltages applied to gates of the self arc-suppressing elements Q, Qupon driving are provided. Furthermore, thyristors S, Sare driven by the voltages across the shunt resistors R, Rgenerated when overcurrent larger than predetermined current flows through the shunt resistors R, R

Electronic switch

In a phase controller used in a light control of an incandescent lamp, noise reduction, prevention of elements from damage due to short circuit current, downsizing and lower cost are purposed. A CPU circuit of a control circuit sets a gradual increase term during which a load voltage applied to the incandescent lamp is gradually increased by driving a self-quenching type switching device such as an IGBT. After passing the gradual increase term, a main switching device such as a TRIAC is turned on. The phase controller further comprises a current sensor such as a shunt resistor for sensing a value of the load current flowing through the self-quenching type switching device, according to need. The CPU circuit compares the sensed value of the load current with at least one reference value, and selects driving manner of the main switching device and the self-quenching type switching device corresponding to the result of comparison.

Phase controller

A solar battery SB for detecting the surrounding brightness is provided and a switching element SW is controlled based on output voltage of the solar battery SB. The switching element SW is made up of MOSFETs Q and Q . To form an electronic automatic on/off switch, a triac Q is controlled by turning on/off the switching element SW.

Illumination sensor with spectral sensitivity corresponding to human luminosity characteristic

An electromagnet drive apparatus being characterized by a switching element 1 connected in series with a coil 3 of an electromagnet; a pulse signal generation circuit 16 which generates, on predetermined cycles, a pulse signal used for turning on the switching element; a regenerative circuit 4 which permits flow of a regenerated electrical current when the switch section is turned on and the switching element is turned off from a state in which the switch section and the switching element are in an on state and a source voltage is applied to the coil of the electromagnet, and which causes the power absorbing element to immediately reduce the regenerated electrical current flowing through the coil of the electromagnet when the switch section and the switching element are turned off; and a delay circuit 11 which turns on the switch section by application of the supply voltage and maintains the switch section in an on state until a predetermined period of time elapses after the application of the supply voltage has been stopped.

Growing community of inventors

Hirakata, Japan

Yukihiro Murata