Abstract: A power conversion apparatus includes an input power terminal, an output power terminal, a power conversion circuit, a signal generation circuit, and a control circuit. The power conversion circuit converts supplied electric power and outputs the converted electric power. The power conversion circuit includes a sensor that generates a first detection signal corresponding to an output voltage or an output current. The signal generation circuit generates a second detection signal corresponding to the first detection signal. The control circuit controls operation of the power conversion circuit. The signal generation circuit includes a corrector, a photocoupler, and an output circuit. The corrector performs correction processing on the first detection signal. The photocoupler includes a light receiving device generating a light reception signal. The output circuit outputs the second detection signal corresponding to the light reception signal.

Abstract: A converter device includes a plurality of converters, a voltage detector, a temperature detector, and a controller. The plurality of converters are connected in series or in parallel. Each of the plurality of converters includes at least one switch element controlled according to a drive signal. The voltage detector detects information about an output voltage of a converter circuit unit in which the plurality of converters are connected. The temperature detector detects information about temperatures of one or more of semiconductor elements including the switch element in each of the plurality of converters. The controller controls the drive signal for the switch element in each converter so that temperatures of semiconductor elements having highest temperatures in the plurality of converters are closed to each other on the basis of detection results of the voltage detector and detection results of the temperature detector.

Abstract: A power supply includes a synchronous rectification-type rectifying/smoothing circuit to increase the conversion efficiency of an output voltage, avoids cost increases, and can change the output voltage and maximum output current. The power supply includes synchronous rectifiers connected to secondary windings of a transformer, smoothing circuits that smooth a voltage outputted from the synchronous rectifiers to produce an output voltage, switch drivers that correspond to the synchronous rectifiers and operate on one or both of the output voltage outputted from the smoothing circuits connected to the synchronous rectifiers and an AC voltage generated in the secondary windings to drive synchronous rectification switches of the synchronous rectifiers, and an output connector that is disposed following the smoothing circuits and connects the outputs of the smoothing circuits in a connection pattern selected out of serial and parallel.

Abstract: A power supply includes: a power factor correction circuit that includes a capacitor and converts an input voltage, produced by rectifying an AC input voltage, to a DC, output voltage; a current detector that detects an inflow current for the power factor correction circuit and outputs a current detection signal; an output voltage detector that detects the output voltage and outputs an output voltage detection signal; a voltage difference detector that detects a voltage difference between maximum and minimum values of a pulsation component of the output voltage detected from the output voltage detection signal; a working life determiner that compares the voltage difference and a threshold and gives notification of end of life of the capacitor when the voltage difference reaches the threshold; and a threshold updater that updates the threshold in keeping with the detected inflow current detected based on the current detection signal.

Abstract: A power supply can be driven in parallel in a master-slave arrangement using fewer wires. Each power supply includes: input terminals; output terminals; a master terminal; a slave terminal; a switching power supply that switches an inputted voltage and executes one of a constant-voltage operation that outputs a DC voltage of a target voltage value and a constant-current operation that outputs a DC current of a target current value; an indicative voltage generator that generates a current detection signal indicating the current outputted from the output terminals, superimposes a bias voltage (>a threshold voltage), and outputs to the master terminal; and an operation switcher that compares a voltage applied to the slave terminal and the threshold voltage and outputs, based on the result, a control signal for switching to the constant-voltage operation or the constant-current operation, to the switching power supply.

Abstract: A power supply includes: a power factor correction circuit that includes a capacitor and converts an input voltage, produced by rectifying an AC input voltage, to a DC, output voltage; a current detector that detects an inflow current for the power factor correction circuit and outputs a current detection signal; an output voltage detector that detects the output voltage and outputs an output voltage detection signal; a voltage difference detector that detects a voltage difference between maximum and minimum values of a pulsation component of the output voltage detected from the output voltage detection signal; a working life determiner that compares the voltage difference and a threshold and gives notification of end of life of the capacitor when the voltage difference reaches the threshold; and a threshold updater that updates the threshold in keeping with the detected inflow current detected based on the current detection signal.

Abstract: A power supply can be driven in parallel in a master-slave arrangement using fewer wires. Each power supply includes: input terminals; output terminals; a master terminal; a slave terminal; a switching power supply that switches an inputted voltage and executes one of a constant-voltage operation that outputs a DC voltage of a target voltage value and a constant-current operation that outputs a DC current of a target current value; an indicative voltage generator that generates a current detection signal indicating the current outputted from the output terminals, superimposes a bias voltage (>a threshold voltage), and outputs to the master terminal; and an operation switcher that compares a voltage applied to the slave terminal and the threshold voltage and outputs, based on the result, a control signal for switching to the constant-voltage operation or the constant-current operation, to the switching power supply.

Abstract: A power supply includes a synchronous rectification-type rectifying/smoothing circuit to increase the conversion efficiency of an output voltage, avoids cost increases, and can change the output voltage and maximum output current. The power supply includes synchronous rectifiers connected to secondary windings of a transformer, smoothing circuits that smooth a voltage outputted from the synchronous rectifiers to produce an output voltage, switch drivers that correspond to the synchronous rectifiers and operate on one or both of the output voltage outputted from the smoothing circuits connected to the synchronous rectifiers and an AC voltage generated in the secondary windings to drive synchronous rectification switches of the synchronous rectifiers, and an output connector that is disposed following the smoothing circuits and connects the outputs of the smoothing circuits in a connection pattern selected out of serial and parallel.

Abstract: A power supply includes: a power converter that converts an input voltage by switching at a switch and supplies an output voltage and an output current to an output terminal connected to a load; a current detector that detects the output current or a current that changes with the output current and outputs a current detection signal whose voltage value changes with the output current; a signal corrector that inputs and corrects the current detection signal and generates and outputs a corrected current detection signal whose voltage value corresponds to the value of the output current; a matching circuit that inputs the corrected current detection signal and outputs to a balanced terminal; and a controller that inputs the corrected current detection signal and a balanced voltage signal generated at the balanced terminal and controls switching operations of the switch to reduce a difference between the two signals.

Abstract: A power supply includes: a power converter that converts an input voltage by switching at a switch and supplies an output voltage and an output current to an output terminal connected to a load; a current detector that detects the output current or a current that changes with the output current and outputs a current detection signal whose voltage value changes with the output current; a signal corrector that inputs and corrects the current detection signal and generates and outputs a corrected current detection signal whose voltage value corresponds to the value of the output current; a matching circuit that inputs the corrected current detection signal and outputs to a balanced terminal; and a controller that inputs the corrected current detection signal and a balanced voltage signal generated at the balanced terminal and controls switching operations of the switch to reduce a difference between the two signals.

Abstract: A control device and method are provided for a power supply device which can perform stable constant voltage constant current control with high responsiveness with a simple configuration. The control device includes: a voltage difference value generation unit which subtracts an output voltage value from a voltage target value to generate a voltage difference value; a current difference value generation unit which subtracts an output current value from a current target value to generate a current difference value; a difference value selection unit which compares the voltage difference value or a value based on the voltage difference value with the current difference value or a value based on the current difference value, and selects the smaller one as a control difference value; and an operation amount generation unit which generates an operation amount for controlling the power supply device based on the control difference value.

Abstract: A control device and method are provided for a power supply device which can perform stable constant voltage constant current control with high responsiveness with a simple configuration. The control device includes: a voltage difference value generation unit which subtracts an output voltage value from a voltage target value to generate a voltage difference value; a current difference value generation unit which subtracts an output current value from a current target value to generate a current difference value; a difference value selection unit which compares the voltage difference value or a value based on the voltage difference value with the current difference value or a value based on the current difference value, and selects the smaller one as a control difference value; and an operation amount generation unit which generates an operation amount for controlling the power supply device based on the control difference value.

Abstract: A bidirectional DC-DC converter is configured with a transformer that has a first winding and a second winding, a first DC-AC converter that is provided between a first DC voltage line and the first winding, a second DC-AC converter that is provided between a second DC voltage line and the second winding, and a controller that performs a switching control operation that bidirectionally transmits DC power between the first DC voltage line and the second DC voltage line. When the bidirectional DC-DC converter is in a light load operation state, the controller provides an operation stop period that periodically stops the switching control operation so as to perform an intermittent switching control operation.

Abstract: A controller controls a voltage-source power converter and a current-source power converter based on a detection value of a rail voltage input to the voltage-source power converter and a detection value of a charging voltage output from the current-source power converter, at the time of charging operation.

Abstract: A current-fed isolation converter includes a coil that is connected to a primary side of a transformer, a power source that supplies electric power to the primary side of the transformer, a switching element that controls a first electric current flowing in the coil, a snubber circuit that includes a rectifying element and a capacitive element that is charged by a second electric current flowing in the rectifying element, and a step-down power supply circuit that regenerates electric charge of the capacitive element to the power source. The snubber circuit controls an excess voltage that is generated when the switching element is turned off. The power supply circuit maintains a charging voltage of the capacitive element at a predetermined voltage value.

Abstract: A controller controls a voltage-source power converter and a current-source power converter based on a detection value of a rail voltage input to the voltage-source power converter and a detection value of a charging voltage output from the current-source power converter, at the time of charging operation.

Abstract: A DC-DC converter is configured with a voltage-source power converter at a primary side of a transformer, a current-source power converter at a secondary side of the transformer, and a controller. The DC-DC converter is connected between a storage battery and an inverter that drives an electric motor. The controller generates a first control input based on a voltage between input and output terminals of the voltage-source power converter, a second control input based on a voltage between input and output terminals of the current-source power converter, and a command value for PWM or PFM control based on the first and second control inputs and an input-output current flowing between one of the input and output terminals of the voltage-source power converter and the current-source power converter. Therefore, it is easy to switch between a powering state and a regenerating state.

Abstract: A DC-DC converter is configured with a voltage-source power converter provided at a primary side of a transformer, a current-source power converter provided at a secondary side of the transformer, and a controller. The controller generates a first control input based on a voltage between input and output terminals of the voltage-source power converter, a second control input based on a voltage between input and output terminals of the current-source power converter, and a command value for PWM or PFM control based on the first and second control inputs and an input-output current flowing between one of the input and output terminals of the voltage-source power converter and the current-source power converter. Therefore, it is easy to switch between a powering state and a regenerating state in the DC-DC converter.

Abstract: A DC-DC converter is configured with a voltage-source power converter at a primary side of a transformer, a current-source power converter at a secondary side of the transformer, and a controller. First and second voltage detection circuits respectively detect first and second voltages of the voltage-source and the current-source power converters. A current detection circuit detects an input-output current of the current-source power converter. The controller controls the voltage-source and the current-source power converters to transfer power between the primary side and the secondary side of the transformer. The controller includes a calculation unit that performs calculations based on the first voltage, the second voltage and the input-output current, and a table unit that include a plurality of parameter sets. The calculation unit performs the calculations based on one of the plurality of parameter sets that is selected from the table unit.

Abstract: A DC-DC converter is configured with a step-down converter that outputs a output voltage having the same voltage value as an input voltage when a step-down operation stops and that outputs the first output voltage having a lower voltage value than the input voltage when the step-down operation is performed, and a resonant converter in which a voltage transfer factor is adjusted by a switching frequency of a switching element through which a resonance current flows. A step-down operation of the step-down converter is performed when the switching frequency, the voltage transfer factor and a target value for the output voltage satisfy a predetermined condition. According to the above configuration, it is possible to decrease switching loss of the step-down converter.