Abstract:
A converter to which an alternating current is inputted from an AC power supply rectifies the alternating current to output it to a DC link. An inverter is connected through the DC link to the converter and converts a direct current into an alternating current to output it to a load. A leakage current detector outputs a detection current corresponding to a leakage current leaking from the load. A compensating current output end is connected to a location where the leakage current leaks, and outputs a compensating current compensating for the leakage current in response to the detection current. A switch sets whether to input the detection current to the compensating current output section or not.
Abstract:
A converter to which an alternating current is inputted from an AC power supply rectifies the alternating current to output it to a DC link. An inverter is connected through the DC link to the converter and converts a direct current into an alternating current to output it to a load. A leakage current detector outputs a detection current corresponding to a leakage current leaking from the load. A compensating current output end is connected to a location where the leakage current leaks, and outputs a compensating current compensating for the leakage current in response to the detection current. A switch sets whether to input the detection current to the compensating current output section or not.
Abstract:
A diode bridge has a pair of input ends to which an alternating current is inputted from an AC power supply, and a pair of output ends which output a direct current. A boost chopper circuit is connected to the pair of output ends, and sets up a DC voltage inputted thereto. The boost chopper circuit functions as a power factor correction circuit. A smoothing capacitor is connected to an output side of the boost chopper circuit, and smoothes the voltage across the smoothing capacitor. An inverter receives the voltage across the smoothing capacitor to apply AC power to a load. A leakage current reduction device outputs a compensating current which compensates for a leakage current leaking from the load. The leakage current reduction device outputs the compensating current, except near the zero crossing of an AC voltage inputted from the AC power supply.
Abstract:
An object is to improve the accuracy of power factor adjustment. Power-factor command values corresponding to individual wind turbines are determined by correcting a predetermined power-factor command value for an interconnection node using power factor correction levels set for the individual wind turbines.
Abstract:
A power factor correction system includes a rectifier that rectifies the voltage of an alternating current (ac) power source to produce a voltage waveform that transitions, in a half sinusoid, from a minimum amplitude to a maximum amplitude and back to the minimum amplitude twice in the period of the ac power source. A phase winding of a motor conveys current induced by the voltage waveform, and a regulator regulates the flow of the current conveyed by the phase winding for storage as energy in a storage component.
Abstract:
A motor control system includes a control module, a switching module, and a filtering module. The control module determines output voltages for operating a motor based on a torque demand. The switching module generates switching signals for an inverter that drives the motor. The switching module generates the switching signals based on the output voltages. The switching module generates an out-of-volts (OOV) signal according to a comparison based on the output voltages, a maximum duty cycle, and a voltage of a direct current (DC) bus that provides power to the inverter. The filtering module generates an OOV amount by filtering the OOV signal. The control module selectively limits the torque demand based on the OOV amount.
Abstract:
A type of portable chargers with power factor correction capability for use with electric vehicles comprises of a filtering rectifier module, an integrated circuit power supply module, a DC-DC PFC module and a DC-DC BUCK module. The filtering rectifier module has one input port and two output ports. The IC power supply module has one input port and two output ports. The DC-DC PFC module has two input ports and one output port. The DC-DC BUCK module has two input ports and one output port. The two output ports of the filtering rectifier module are connected to the input port of IC power supply module and the input port of the DC-DC PFC module respectively. The output port of the DC-DC PFC module is connected to one of the input ports of the DC-DC BUCK module. The two output ports of IC power supply module are connected, respectively, to the other input port of the DC-DC PFC module and to the other input port of the DC-DC BUCK module. This new type of portable chargers embodied with this invention can effectively reduce reactive power in the power system and develop greater power.
Abstract:
A type of portable chargers with power factor correction capability for use with electric vehicles comprises of a filtering rectifier module, an integrated circuit power supply module, a DC-DC PFC module and a DC-DC BUCK module. The filtering rectifier module has one input port and two output ports. The IC power supply module has one input port and two output ports. The DC-DC PFC module has two input ports and one output port. The DC-DC BUCK module has two input ports and one output port. The two output ports of the filtering rectifier module are connected to the input port of IC power supply module and the input port of the DC-DC PFC module respectively. The output port of the DC-DC PFC module is connected to one of the input ports of the DC-DC BUCK module. The two output ports of IC power supply module are connected, respectively, to the other input port of the DC-DC PFC module and to the other input port of the DC-DC BUCK module. This new type of portable chargers embodied with this invention can effectively reduce reactive power in the power system and develop greater power.