Abstract: A resonant current limiting device, for a resonant current passage having a loop shape including at least one capacitor and a wiring passage with at least one inductor or inductance component, includes: an electric storage element connected in series with the capacitor; a driving power source; and a voltage controller that charges and discharges an electric charge in the electric storage element, which is supplied from the driving power source, controls a terminal voltage of the electric storage element to be a predetermined instruction voltage, and restricts a resonant current component flowing through the wiring passage.

Abstract: In a switching regulator, a control circuit includes a reference command value generation portion and an additional command value generation portion. The reference command value generation portion generates a reference command value based on a deviation of an output voltage from a predetermined command voltage. The additional command value generation portion generates an additional command value based on a difference between an outflow electric energy and an inflow electric energy. The outflow electric energy is a value reflecting a supply power from the capacitor to the load, and the inflow electric energy is a value reflecting a supply power from the reactor to the capacitor. The control circuit controls an operation ratio of a switching circuit based on the reference command value and the additional command value.

Abstract: In a power conversion apparatus, a secondary winding is connected between main terminals of one of two circuit elements included in a main series circuit, and a voltage applied to a primary winding induces a voltage in a secondary winding in a direction from a first main terminal of a secondary winding, which is disposed at a low-potential side of the main series circuit, toward a second main terminal of a secondary winding, which is disposed at a high-potential side of the main series circuit. A rectifying unit blocks a current flowing from the high-potential side of the main series circuit toward the low-potential side of the main series circuit in a current path that includes the secondary winding and bypasses one of the two circuit elements included in the main series circuit.

Abstract: An induction heating apparatus includes: a core that has a pair of magnetic poles and transfers magnetic flux; a coil generating magnetic flux; conductors adjacently provided on both left and right sides of the magnetic poles; and lateral magnetic members formed of a magnetic material and arranged on an outer side of end portions of the object so as to extend along the end portions. The conductors shut off the magnetic flux that flows from a center portion of the heating object, taking a detour to the end portions, permit the magnetic flux to concentrate on the center portion, and accelerate temperature rise. The lateral magnetic members introduce the magnetic flux that propagates from one surface to the other surface, detouring around the end portions to thereby mitigate the magnetic flux density in the end portions and suppress overheating.

Abstract: In a power converter, at least two main current paths each including an inductor and a transistor are connected between input terminals, and at least two storage circuits each including capacitors are correspondingly connected to branch nodes of the main current paths. Diodes are connected between the storage circuits. The transistors of the main current paths are interleaved. When one of the transistors is turned off, a current flowing in the corresponding inductor flows into the corresponding storage circuit to turn on the diodes and to charge the capacitors of the corresponding storage circuit. When another one of the transistors is turned off, a current flowing in the corresponding inductor flows into the corresponding storage circuit to turn on the diodes and charge the capacitors of the corresponding storage circuit.

Abstract: A transformer device includes a magnetic core, a normal winding, a main magnetic path, and a specific winding including A sections and B sections formed by winding a conductive wire around the magnetic core toward opposite directions. A total number of turns of the conductive wire is different between the A sections and the B sections. At least one section in the specific winding is arranged to form a sub-magnetic path which is a magnetic path not interlinked with the normal winding.

Abstract: An AC-DC converter includes two series circuits, an inductor, and a common snubber circuit. Each series circuit includes a switch and a current block device. The block device blocks a current from its high potential side to its low potential side when the first device is closed and allows the current from the low potential side to the high potential side when the first device is opened. The inductor is interposed between a first connection point between the switch and the block device of one series circuit and a second connection point between the switch and the block device of the other series circuit. The common snubber circuit is connected between each of the first connection point and the second connection point and at least one of both ends of the one series circuit.

Abstract: A driver circuit for a semiconductor switching device includes a drive power source, a capacitor and four switches, which form a bridge circuit. The capacitor is provided between the four switches. In one cycle of application of a voltage to a gate of the semiconductor switching device to turn on the semiconductor switch, the first and the second switches, which are diagonal, are turned off and the third and the fourth switches, which are diagonal, are turned on to charge the capacitor. Then only the first switch is turned on to apply the voltage to the gate, and lastly only the second switch is turned on to discharge the capacitor thereby to apply a negative voltage to the gate of the semiconductor switching device.

Abstract: A series circuit of a diode Da1, capacitors Ca1, Ca2 and a diode Da2 is connected in parallel to a series circuit of switching elements S1 and S2. A common junction between the capacitors Ca1 and Ca2 is connected to an emitter of the switching element S2. A series circuit of a switching element Sa1 and a diode Da1 is connected between a cathode of the diode Da1 and a cathode of the diode Da2. A series circuit of a diode Da4 and a switching element Sa2 is connected between an anode of the diode Da1 and the ground. A reactor La1 is connected between a source of the switching element Sa1 and a drain of the switching element Sa2.

Abstract: In a current detection circuit, a first circuit is connected between a first terminal and a second terminal, and a second circuit is connected between a third terminal and a fourth terminal. The second terminal and the fourth terminal are commonly connected. When a first current flows between the first and second terminals, voltage drop occurs in the first circuit. A current control circuit controls the first current to make an application voltage between the first and second terminals substantially same as an application voltage between the third and fourth terminals. When the first circuit has voltage drop same as the second circuit, the first current has the amount proportional to the second current. A detection circuit detects a current flowing between the first terminal and the third terminal by detecting the first current controlled by the current control circuit or the second current.

Abstract: A filter component is provided with a first winding wire, a second winding wire having a separate electric current supply from the first winding wire, and a third winding wire connected in series with the first winding wire. The first, second, and third winding wires are wound on a magnetic core. The magnetic core has a shape that allows a formation of a first magnetic path having the first and second winding wires interlinked therewith without having the third winding wire interlinked therewith, and a formation of a second magnetic path having the first and third winding wires interlinked therewith without having the second winding wire interlinked therewith. Further, the electric current flow directions of the first and second winding wires are opposite and the electric current flow directions of the first and third winding wires are the same.

Abstract: A driver circuit for a semiconductor switching device includes a drive power source, a capacitor and four switches, which form a bridge circuit. The capacitor is provided between the four switches. In one cycle of application of a voltage to a gate of the semiconductor switching device to turn on the semiconductor switch, the first and the second switches, which are diagonal, are turned off and the third and the fourth switches, which are diagonal, are turned on to charge the capacitor. Then only the first switch is turned on to apply the voltage to the gate, and lastly only the second switch is turned on to discharge the capacitor thereby to apply a negative voltage to the gate of the semiconductor switching device.

Abstract: A detector includes a detection winding, a detection winding measurement section, and a detection section. A magnetic core has a hole penetrating the magnetic core along a non-uniform cross section. The detection winding includes a wire inserted into the hole and surrounding a periphery of a detection region that is a part of the non-uniform cross section and has a magnetic flux density different from an average magnetic flux density of the non-uniform cross section. The detection winding measurement section performs a measurement relating to an electromotive force induced by the detection winding. The detection section detects a magnetic bias, a magnetic saturation, or an amount of magnetic flux in the magnetic core based on a measurement result of the detection winding measurement section.

Abstract: In a switching regulator, a power feed circuit section includes a reactor, a capacitor, and a switching circuit controlling power supply from a power supply source to the reactor. A reference command value generation portion generates a reference command value based on a physical quantity representing a state of the power feed circuit section. An adder adds a pseudo command value depending on a reactor current flowing in the reactor to the reference command value. A limiter limits at least one of an upper limit value and a lower limit value with respect to an adding result of the adder. A removing section removes a value corresponding to the pseudo command value from a processing result of the limiter. A control performing section controls a duty ratio of the switching circuit using a processing result of the removing section as a command value.

Abstract: An AC-DC converter includes two series circuits, an inductor, and a common snubber circuit. Each series circuit includes a switch and a current block device. The block device blocks a current from its high potential side to its low potential side when the first device is closed and allows the current from the low potential side to the high potential side when the first device is opened. The inductor is interposed between a first connection point between the switch and the block device of one series circuit and a second connection point between the switch and the block device of the other series circuit. The common snubber circuit is connected between each of the first connection point and the second connection point and at least one of both ends of the one series circuit.

Abstract: In a switching regulator, a control circuit includes a reference command value generation portion and an additional command value generation portion. The reference command value generation portion generates a reference command value based on a deviation of an output voltage from a predetermined command voltage. The additional command value generation portion generates an additional command value based on a difference between an outflow electric energy and an inflow electric energy. The outflow electric energy is a value reflecting a supply power from the capacitor to the load, and the inflow electric energy is a value reflecting a supply power from the reactor to the capacitor. The control circuit controls an operation ratio of a switching circuit based on the reference command value and the additional command value.

Abstract: A driving circuit that drives a semiconductor device includes first to sixth semiconductor devices. A first state and a second state are provided in one cycle in which a voltage is applied to a control terminal of the semiconductor device. In the first state, the first semiconductor device is closed, the third and fourth semiconductor devices are opened, and when the second semiconductor device is structured to have a semiconductor switch, the semiconductor switch is closed. In the second state, the first semiconductor device is opened, and the third and fourth semiconductor devices are closed.

Abstract: A power converter includes a main switch to which a capacitor is connected through a sub-diode. A series connection of a primary coil of a transformer and a sub-switch is connected parallel to the capacitor. A main diode is coupled in series with the main switch. A series connection of a sub-diode and a secondary coil of the transformer is parallel to the main diode. The rate of a rise in voltage across the main switch when turned off is suppressed by the rate of charging of the capacitor. Subsequently, by turning on the sub-switch, the current flowing through the main diode to be delivered to the transformer, thereby causing the current flowing through the main switch when turned on to be decreased by the sub-inductor.

Abstract: A power converter includes a main switch to which a capacitor is connected through a sub-diode. A primary coil of a transformer and a sub-switch are joined parallel to the capacitor. A main diode is coupled in series with the main switch. A sub-diode and a secondary coil of the transformer are connected parallel to the main diode. The rate of a rise in voltage across the main switch when turned off is suppressed by the rate of charging of the capacitor. Subsequently, by turning on the sub-switch, the current flowing through the main diode to be delivered to the transformer, thereby causing the current flowing through the main switch when turned on to be decreased by the sub-inductor.

Abstract: A power converter including a main circuit and a sub-circuit. The main circuit serves as a step-up/down chopper circuit including a series-connected assembly of main switches, an inductor coupled to a joint of the main switches, and a capacitor connected in parallel to the series-connected assembly. The sub-circuit is designed to establish the soft-switching and includes a snubber capacitor, a first sub-switch coupled to the joint of the series-connected assembly and a negative terminal of the snubber capacitor, a second sub-switch coupled to the joint and a positive terminal of the snubber capacitor, a third sub-switch coupled to the positive terminal of the snubber capacitor and a high-potential terminal of the main circuit, and a fourth sub-switch coupled to the negative terminal of the snubber capacitor and a low-potential terminal of the main circuit.