摘要:
A plasma-generation power-supply device includes a transformer connected to an alternating-current power-supply, a rectifier connected to the transformer, an inverter connected to the rectifier, a reactor inserted in series in a power line of an ozonizer that is supplied with power from the inverter, and a controller that controls the inverter. The controller detects the current flowing to the ozonizer with a current detector and provides a control that keeps power applied to the ozonizer constant.
摘要:
A plasma-generation power-supply device includes a transformer connected to an alternating-current power-supply, a rectifier connected to the transformer, an inverter connected to the rectifier a reactor inserted in series in a power line of an ozonizer that is supplied with power from the inverter, and a controllers that controls the inverter. The controller detects the current flowing to the ozonizer with a current detector and provides a control that keeps power applied to the ozonizer constant.
摘要:
In a power conversion apparatus that converts AC power to DC power, an inverter circuit including one or more single-phase inverters connected in series with each other is connected in series at the subsequent stage of a rectification of an AC input. At the subsequent stage of the inverter circuit, a smoothing capacitor connected via a rectification diode, and a short-circuiting switch for bypassing the smoothing capacitor are provided. The short-circuiting switch is subjected to ON/OFF control by PWM control such that a voltage of the DC voltage supply of the inverter circuit follows a target voltage. The inverter circuit is subjected to output control such that a DC voltage of the smoothing capacitor follows a target voltage and an input power factor is improved.
摘要:
A power converting apparatus includes a first inverter (3) connected to a first DC power supply (1) and a plurality of second inverters (4A, 4B) connected in series to the first DC power supply (1). The plurality of second inverters (4A, 4B) provide compensation to an output voltage of the first inverter (3) by the sum of outputs at which a power balance becomes approximately zero. The power converting apparatus generates output voltage commands (VrefA, VrefB) for the respective second inverters (4A, 4B) upon individually making an adjustment so that DC bus voltages of the second inverters (4A, 4B) become equal to each other depending on whether charging or discharging mode is selected while keeping the sum of the individual output voltage commands (VrefA, VrefB) at a target sum voltage (Vref2).
摘要:
There are provided a smoothing capacitor (71) for storing an induced electromotive force generated by a three-phase induction motor (5), a regenerative transistor (81 to 86) for switching a terminal voltage of the smoothing capacitor to carry out a power regenerating operation over a three-phase AC power supply (3), a line voltage detecting portion (6) for detecting a line voltage of the three-phase AC power supply, a fundamental waveform generating portion (10) for generating, from a signal output from the line voltage detecting portion, a fundamental waveform defined to be a line voltage waveform of the three-phase AC power supply in which a source voltage distortion component is not mixed, a base driving signal creating portion (7) for creating a base driving signal to be used for an ON/OFF control of the regenerative transistor based on a signal output from the fundamental waveform generating portion, and a base driving signal output portion (9) for outputting the base driving signal.
摘要:
A power converting apparatus includes a main inverter having a high-voltage DC power supply that operates at a low frequency employing SiC MOSFETs having a high withstand voltage exceeding 600 V and a sub-inverter having a low-voltage capacitor that operates through high-frequency PWM employing Si MOSFETs having a low withstand voltage. With AC sides of the main inverter and the sub-inverter connected in series, the power converting apparatus outputs AC power having a prescribed voltage waveform by adding voltages individually generated by the main inverter and the sub-inverter. Specifically, the SiC MOSFETs are used only in the main inverter of which devices are required to have a high withstand voltage and the Si MOSFETs are used in the sub-inverter of which devices may have a relatively low withstand voltage, whereby conduction loss is reduced with an inexpensive circuit configuration.
摘要:
Three or more circuits including a driving inverter circuit and rectifier circuits are connected in series, each of the circuits including a high-voltage side MOSFET and a low-voltage side MOSFET connected in series as well as a smoothing capacitor having positive and negative terminals between which the MOSFETs are connected. LC series circuits, each including a capacitor and an inductor, are disposed individually between one specific circuit and the other circuits with periods of resonance of the LC series circuits made equal to one another. In performing DC/DC power conversion through charging and discharging operation of the capacitors, a resonance phenomenon of the LC series circuits is used to improve conversion efficiency and achieve a reduction in size of the apparatus structure.
摘要:
In a power conversion apparatus that converts AC power to DC power, an inverter circuit including one or more single-phase inverters connected in series with each other is connected in series at the subsequent stage of a rectification of an AC input. At the subsequent stage of the inverter circuit, a smoothing capacitor connected via a rectification diode, and a short-circuiting switch for bypassing the smoothing capacitor are provided. The short-circuiting switch is subjected to ON/OFF control by PWM control such that a voltage of the DC voltage supply of the inverter circuit follows a target voltage. The inverter circuit is subjected to output control such that a DC voltage of the smoothing capacitor follows a target voltage and an input power factor is improved.
摘要:
A neutral point clamped three-phase three-level inverter is connected to a first DC power supply and single-phase inverters are connected in series with AC output lines of individual phases of the three-phase three-level inverter such that sums of output voltages of the three-phase three-level inverter and output voltages of the respective single-phase inverters are output to a load through a smoothing filter. An output control unit controls the three-phase three-level inverter so that the individual phases of the three-phase three-level inverter output primary voltage pulses at a rate of one pulse per half cycle and controls the individual single-phase inverters by PWM, so that output voltages to the individual phases of the load form sine waves of which phases are offset by 2π/3 from one phase to another, the sine waves having the same peak value.
摘要:
A converter controllable in regenerative running mode, which is a power converting apparatus capable of suppressing harmonics without increasing the size of a reactor, and reducing power loss and electromagnetic noise. A power converter is configured by directly connecting AC sides of single-phase sub-converters having a DC voltage lower than a DC voltage of a 3-phase main converter to AC input lines of individual phases thereof in series. The main converter is driven by one gate pulse per half recurring cycle and a voltage produced by each sub-converter at AC terminals thereof is controlled to match a difference between an AC power supply voltage and a voltage produced by the main converter at AC terminals thereof, whereby phase voltages of the power converter are generated as the sums of phase voltages of the individual converters.