Abstract: A power converter stabilizes a voltage by controlling leading of an AC current and performs maximum charging within contracted power reception amount when connected to a weak power system. The power converter comprises Magnetic Energy Recovery Switch comprising a bridge circuit including at least two reverse conductive type semiconductor switches and a magnetic energy accumulating capacitor with a small capacity connected between DC terminals of the bridge circuit. The power converter uses the Magnetic Energy Recovery Switch to perform power conversion from AC to DC or vise versa. Plurality of secondary battery charging devices each comprising the power converter have a DC part connected to a common DC bus bar, so that power is accommodated among the secondary battery charging devices.

Abstract: The alternating voltage control apparatus which is inserted serially between an alternating-current power source and an inductive load and which controls adjustment of load voltage of the inductive load with a magnetic energy recovery switch reduces a voltage burden of a reverse conduction type semiconductor switch within the magnetic energy recovery switch and a capacitor and controls voltage to be supplied to the inductive load with a small advancing amount of a phase of current to be supplied to the inductive load.

Abstract: A protected power conversion device (1) includes a full-bridge MERS (100), a control circuit (200), and an ammeter (300), and is connected between a DC current source (2) and an inductive load (3). The ammeter (300) measures a current value supplied to the inductive load (3). The control circuit (200) changes the states of four reverse-conductive semiconductor switches (SW1) to (SW4) configuring the full-bridge MERS (100) to convert power output by the DC current source (2) into AC power, and supplies the AC power to the inductive load (3). When, for example, the inductive load (3) is short-circuited and malfunctions, a large current flows therethrough, and the current value detected by the ammeter (300) becomes equal to or greater than a predetermined value, the control circuit (200) turns OFF all reverse-conductive semiconductor switches (SW1) to (SW4) to cut OFF the large current.

Abstract: A protection circuit equipped magnetic energy recovery switch including a magnetic energy recovery switch having at least two reverse-conductive type semiconductor switches and two capacitors employs a protection circuit and control method for protecting the capacitors against an overvoltage or short-circuited discharge, and protecting the reverse-conductive type semiconductor switches and a load against an overvoltage or overcurrent, and can be used as a controller or a current limiter.

Abstract: A power conversion device (1) comprises an inductor (L) serried-connected to an alternating-current power source (20) and a load (30), a full-bridge MERS (100) parallel-connected to the load (30), a control circuit (110), a current direction switching part (200) serried-connected between the inductor (L) and load (30), and an ammeter (300). The control circuit (110) feeds back the current detected by the ammeter (300), repeatedly turns on/off either a pair of reverse conductive semiconductor switches (SW2, SW3) or a pair of reverse conductive semiconductor switches (SW1, SW4) constituting the full-bridge MERS (100), which corresponds to the positive/negative voltage output from the alternating-current source (20), and keeps the other pair being off.

Abstract: A power inverter (1) is provided with a full-bridge circuit (10), a shunt capacitor (CP), and a control circuit (20). The control circuit (20) controls the on/off state of each reverse-conductive semiconductor switch (SW1 to SW4) at a switching frequency of not more than the resonance frequency determined by the capacitance of the shunt capacitor (CP) and the inductance of an inductive load (LD) in such a matter than when a first reverse-conductive semiconductor switch (SW1) and a fourth reverse-conductive semiconductor switch (SW4) are in the on-state, a second reverse-conductive semiconductor switch (SW2) and a third reverse-conductive semiconductor switch (SW3) are brought into the off-state, and that when the first reverse-conductive semiconductor switch (SW1) and the fourth reverse-conductive semiconductor switch (SW4) are in the off-state, the second reverse-conductive semiconductor switch (SW2) and the third reverse-conductive semiconductor switch (SW3) are brought into the on-state.

Abstract: In order to protect Magnetic Energy Recovery Switch (MERS) against an overvoltage and an overcurrent a voltage detection unit is provided for detecting the capacitor voltage of the MERS and control means is provided to control so as to turn ON the switch of the discharge circuit connected in parallel with the capacitor to make the capacitor discharge the electric charge thereof when the output of the voltage detection unit exceeds a predetermined value. Moreover, a current detection unit is interposed between the AC power supply and the load for detecting the current flowing to the load, and the current limiting is carried out by making the duty ratio of the ON/OFF of the pulse of the gate control signals of the MERS switches smaller than 0.5, when the output of the current detection unit exceeds a predetermined value.

Abstract: A power converter stabilizes a voltage by controlling leading of an AC current and performs maximum charging within contracted power reception amount when connected to a weak power system. The power converter comprises Magnetic Energy Recovery Switch comprising a bridge circuit including at least two reverse conductive type semiconductor switches and a magnetic energy accumulating capacitor with a small capacity connected between DC terminals of the bridge circuit. The power converter uses the Magnetic Energy Recovery Switch to perform power conversion from AC to DC or vise versa. Plurality of secondary battery charging devices each comprising the power converter have a DC part connected to a common DC bus bar, so that power is accommodated among the secondary battery charging devices.

Abstract: The alternating voltage control apparatus which is inserted serially between an alternating-current power source and an inductive load and which controls adjustment of load voltage of the inductive load with a magnetic energy recovery switch reduces a voltage burden of a reverse conduction type semiconductor switch within the magnetic energy recovery switch and a capacitor and controls voltage to be supplied to the inductive load with a small advancing amount of a phase of current to be supplied to the inductive load.

Abstract: The present invention provides a PM motor drive power supply apparatus which drives a three-phase permanent-magnet synchronous motor by utilizing a direct-current power source 1, wherein control means 7 controls to simultaneously perform ON/OFF operation of a diagonally positioned pair among reverse conductive semiconductor switches (S1 to S4) of pulse voltage generating means 2, controls to perform ON/OFF operation of switches of three lines of polarity switching means 5 in turns at the same timing as the reverse conductive semiconductor switches (S1 to S4) of the pulse voltage generating means 2, selects a switch of the polarity switching means 5 based on the rotational position signal, converts direct-current pulse output of the pulse voltage generating means 2 into polarities of the three-phase alternating-current, and supplies to a PM motor 4 as drive current.

Abstract: In order to provide a pulse power supply device using regenerating magnetic energy stored in a discharge circuit to a capacitor so as to use it as next discharge energy and supplying a bipolar pulse current with high repetition, a bridge circuit is composed of four inverse-conductive semiconductor switches, a charged energy source capacitor is connected to a DC terminal of the bridge circuit, and an inductive load is connected to its AC terminal. A control signal is supplied to gates of the inverse-conductive semiconductor switches, and a control is made so that when a discharge current rises, is maintained, or is reduced, all the gates are turned off, and the magnetic energy of the electric current can be automatically regenerated to the energy source capacitor by a diode function of the switches. Further, a large current power supply is inserted into a discharge circuit so as to replenish energy loss due to discharge, thereby enabling high-repetition discharge.

Abstract: In order to protect Magnetic Energy Recovery Switch (MERS) against an overvoltage and an overcurrent a voltage detection unit is provided for detecting the capacitor voltage of the MERS and control means is provided to control so as to turn ON the switch of the discharge circuit connected in parallel with the capacitor to make the capacitor discharge the electric charge thereof when the output of the voltage detection unit exceeds a predetermined value. Moreover, a current detection unit is interposed between the AC power supply and the load for detecting the current flowing to the load, and the current limiting is carried out by making the duty ratio of the ON/OFF of the pulse of the gate control signals of the MERS switches smaller than 0.5, when the output of the current detection unit exceeds a predetermined value.

Abstract: The present invention relates to an alternating-current power supply device which can improve a power factor of an alternating-current load, realizes low cost and miniaturization, and recovers magnetic energy. The alternating-current power supply device includes a bridge circuit composed of four reverse conducting semiconductor switches, a capacitor that is connected between direct-current terminals of the bridge circuit and absorbs the magnetic energy at the time of cutting off the current, an alternating-current voltage source that is connected to the induction load in series and is inserted between alternating-current terminals of the bridge circuit, and a control circuit that gives a control signal to gates of the respective reverse conducting semiconductor switches and controls on/off states of the respective reverse conducting semiconductor switches.

Abstract: In order to provide a pulse power supply device using regenerating magnetic energy stored in a discharge circuit to a capacitor so as to use it as next discharge energy and supplying a bipolar pulse current with high repetition, a bridge circuit is composed of four inverse-conductive semiconductor switches, a charged energy source capacitor is connected to a DC terminal of the bridge circuit, and an inductive load is connected to its AC terminal. A control signal is supplied to gates of the inverse-conductive semiconductor switches, and a control is made so that when a discharge current rises, is maintained or is reduced, all the gates are turned off, and the magnetic energy of the electric current can be automatically regenerated to the energy source capacitor by a diode function of the switches. Further, a large-current power supply is inserted into a discharge circuit so as to replenish energy loss due to discharge, thereby enabling high-repetition discharge.

Abstract: The present invention relates to an alternating-current power supply device which can improve a power factor of an alternating-current load, realizes low cost and miniaturization, and recovers magnetic energy. The alternating-current power supply device includes a bridge circuit composed of four reverse conducting semiconductor switches, a capacitor that is connected between direct-current terminals of the bridge circuit and absorbs the magnetic energy at the time of cutting off the current, an alternating-current voltage source that is connected to the induction load in series and is inserted between alternating-current terminals of the bridge circuit, and a control circuit that gives a control signal to gates of the respective reverse conducting semiconductor switches and controls on/off states of the respective reverse conducting semiconductor switches.

Abstract: In order to provide a pulse power supply device using regenerating magnetic energy stored in a discharge circuit to a capacitor so as to use it as next discharge energy and supplying a bipolar pulse current with high repetition, a bridge circuit is composed of four inverse-conductive semiconductor switches, a charged energy source capacitor is connected to a DC terminal of the bridge circuit, and an inductive load is connected to its AC terminal. A control signal is supplied to gates of the inverse-conductive semiconductor switches, and a control is made so that when a discharge current rises, is maintained, or is reduced, all the gates are turned off, and the magnetic energy of the electric current can be automatically regenerated to the energy source capacitor by a diode function of the switches. Further, a large current power supply is inserted into a discharge circuit so as to replenish energy loss due to discharge, thereby enabling high-repetition discharge.