940 results about "Transient current" patented technology

A DC/DC voltage converter includes an inductive switching voltage regulator and a capacitive charge pump connected in series between the input and output terminals of the converter. The charge pump has a second input terminal connected to the input terminal of the converter. This reduces the series resistance in the current path by which charge is transferred from the capacitor in the charge pump to the output capacitor and thereby improves the ability of the converter to respond to rapid changes in current required by the load.

A method and system for detecting and locating a single-phase ground fault on a low current grounded power-distribution network, comprising: respectively testing and picking up the voltage signals and current signals at multiple positions on each phase feeder (61), and determining the corresponding transient voltage signals and transient current signals according to the extraction of the voltage signals and the current signals (62); when the change in the transient voltage signals and the transient current signals exceeds a preset threshold (63), synchronously picking up the voltage signals and current signals at multiple positions on a three-phase feeder (64); calculating corresponding zero-sequence voltages and zero-sequence currents according to the voltage signals and current signals synchronously picked up at multiple positions on the three-phase feeder (65), and then extracting the steady-state signal and transient signal of the zero-sequence voltage and zero-sequence current at each position on the three-phase feeder (66); and determining a specific fault location on a faulty line according to the steady-state signal and the transient signal (67). The method effectively detects and displays a single-phase ground fault on a low current grounded power-distribution network.

An integrated HVACR control and protection system includes a modular and reprogrammable design providing a plurality of possible combinations of power detection, voltage detection, run current detection, transient current detection, temperature detection, universal thermostat interface, peripheral or remote control, and local display and control. The control and protection system is capable of evaluating the relationship between real power used by an HVACR system compressor and other system operating parameters to detect problems early in the failure cycle, i.e., before a failure has progressed to requiring a system shutdown or causing damage to other components. Additionally, a control system and method provide sensorless detection of various HVACR system faults, such as, for example, loss of refrigerant or a refrigerant flow restriction, that impact the relationship between real power and current, voltage, temperature, or other operating parameters. Peripheral or remote control includes wired or wireless system monitoring and parameter programming using a personal digital assistant (PDA), for example utilizing IR communication between the PDA and the control and protection system.

Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect the windings of the motor to a power supply. Asynchronously connecting the windings to the power supply via the asynchronous or non-simultaneous closing of the contactors of a modular contactor assembly reduces the potentially damaging transient current, the associated torque oscillations, and mechanical stresses. The present invention is particularly applicable to delta motors that are started with its windings in a star or wye configuration followed by the reconnection of the windings in a delta configuration when the motor is at normal running speed.

A power control system is disclosed for controlling the power supplied to a lighting system and limiting power during time of peak demands and the like wherein the lighting system includes a power source and a lighting load connected to the power source. The control system comprises a main transformer having a first winding and a second winding, the first winding being connected between the power source and the lighting load. An autotransformer connected to the power source having a plurality of electrical transformer taps with prescribed voltage values. A plurality of solid-state tap switches is connected to the transformer taps and to the second winding of the main transformer to apply the prescribed voltage values across the second winding. A system controller has an input for receiving a voltage change signal representing a selected load voltage to be applied to the lighting load. The controller is connected to the tap switches for selectively closing one of the tap switches to produce said prescribed voltage value across the second winding of the main transformer whereby the selected load voltage is output across the first winding of the main transformer and applied to the lighting load without interruption of the lighting. A transient control circuit is connected across an output of the tap switches for dissipating transient currents during switching of tap switches.

A bi-directional transient voltage suppression (“TVS”) device (101) includes a semiconductor die (201) that has a first avalanche diode (103) in series with a first rectifier diode (104) connected cathode to cathode, electrically coupled in an anti-parallel configuration with a second avalanche diode (105) in series with a second rectifier diode (106) also connected cathode to cathode. All the diodes of the TVS device are on a single semiconductor substrate (301). The die has a low resistivity buried diffused layer (303) having a first conductivity type disposed between a semiconductor substrate (301) having the opposite conductivity type and a high resistivity epitaxial layer (305) having the first conductivity type. The buried diffused layer shunts most of a transient current away from a portion of the epitaxial layer between the first avalanche diode and the first rectifier diode, thereby reducing the clamping voltage relative to the breakdown voltage. The TVS device is packaged as a flip chip (202) that has four solder bump pads (211-214). The abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims pursuant to 37 C.F.R. §1.72(b).

This invention is a methods and devices for detecting the fault of a cage rotor, which belongs to testing technology and for the settlement of broken rotor on the early detection of fault issue. Its technical program: through the acquisition of the stator transient current (is) continuously to do Fourier transform, receiving fundamental wave namely reference signal uS. Do adaptive filtering based the reference signal uS and the frequency f1 for the stator current transient signal. And then filter the output signal eT to do continuous the Fourier transform, identified (1 +- 2s) f1-frequency component and the amplitude of the fundamental components ratio as a failure features, the final determining fault index depending on fault detection threshold index and judge of Broken Bars, This invention can high sensitivity, high reliability and on-line detect the early induction motor of Broken Bars.

The present invention provides a single circuit that may have multiple protection functions for a DC voltage power supply. The present invention may include separate circuit modules that are employed individually, or in various combinations. These separate circuit modules include: a temperature and input voltage variation compensated current limit circuit; an inrush and transient current limit combined with an overload and short circuit protection circuit; and a self adaptive short circuit turn-off timing circuit.

A liquid crystal display device for restraining a generation of transient current is disclosed. In the device, a line memory divides a data for at least one line inputted from the exterior thereof into a plurality of groups to store the divided data therein and outputs the data at a desired unit from each of the groups. A driving circuit includes n driver integrated circuits (wherein n is an integer) that are connected to the line memory and a liquid crystal display panel to drive the liquid crystal display panel in response to the data outputted from the line memory. A timing controller is connected to the line memory and the driving circuit to receive a data clock inputted from the exterior thereof for outputting the data from the plurality of groups of said line memory to the driving circuit every period of the data clock in response to a time corresponding to the number of said groups.

The invention relates to the technical field of display devices, and provides a shift register, a drive device and a displayer. The shift register provided by the invention comprises a valuation unit, a reset control unit and a reset unit. The valuation unit is used for outputting a signal to a signal output end under the control of an input signal and a second clock signal; the reset control unit of which one end is connected with the valuation unit is used for inputting a control signal to the reset unit under the control of a first clock signal and a low-level signal; and the reset unit is used for resetting the signal output end under the control of the control signal and a high-level signal input by the reset control unit. The shift register provided by the invention can quickly charge the grid of a reset transistor grid while valuating the output end, so that the transistor can be turned off in time, a larger transient current generated when the reset transistor and a valuation transistor are switched on at the same time is avoided, the power consumption is reduced and circuit elements are protected. The shift register also can reduce the influence of leakage current from an input tube, reduce the power consumption and enhance the stability based on the output voltage feedback and input tube double-grid technology.

The invention provides a fault line selection method of a low current grounding system using a time-frequency atom decomposition theory. The method comprises the following steps of: based on the time-frequency atom decomposition theory, performing sparse decomposition on zero-sequence current data in a Gabor over-complete dictionary, and then obtaining matched attenuation sinusoidal quantity atoms through optimizing and solving relevant parameters. By the time-frequency atom decomposition method, the disturbance characteristics such as start/stop moments, amplitudes, frequencies and change rules of fundamental wave and each subharmonic can be exactly obtained, and interference signals can be effectively filtered. Energy entropies of the atoms decomposed by time-frequency atoms are arranged from large to small; except from the zero-sequence transient current fundamental wave atom, atom phase angles (polarity) similar with zero-sequence current frequency of each line are compared; if the atom phase angle (polarity) similar with the zero-sequence transient frequency of the line is opposite to that of other lines, the line is the fault line; and if the atom phase angle (polarity) of each line is the same, the fault is bus fault, and the fault line is determined by the comparison result of each frequency phase angle.

The invention discloses a system for detecting malicious circuits in an FPGA (field programmable gate array) chip by power consumption analysis. The system comprises a DC (direct current) stabilized voltage source for supplying DC power to a to-be-detected FPGA chip and an excitation applying FPGA chip; a current probe for measuring a transient current at the power end of the to-be-detected FPGA chip; an oscilloscope triggered by a trigger signal generated by the to-be-detected FPGA chip to collect the current signal measured by the current probe; the excitation applying FPGA chip for applying an excitation signal to the to-be-detected FPGA chip, and transmitting the response signal of the to-be-detected FPGA chip to a computer for further verification and comparison with an expected response value; and the computer for receiving excitation restraint compiled by a user, generating a test vector, and completing response verification, oscilloscope setting, waveform data collection, data analysis and treatment. The invention also discloses a method for detecting malicious circuits in the FPGA chip by using the above system.

System and method for providing power to circuitry while avoiding a large transient current. A preferred embodiment comprises a distributed switch (such as switch arrangement 400) with a plurality of switches (such as switch 405) coupling a power supply to the circuitry. Each switch is individually controlled by a control signal and is turned on sequentially. Also coupled to each switch is a pre-driver circuit (such as pre-driver circuit 410). The pre-driver circuit comprises a potential adjust circuit (such as potential adjust circuit 505) that rapidly adjusts a voltage potential at the switch and a rate adjust circuit (such as the rate adjust circuit 520) that accelerates the power ramp-up across the switch once transient currents are no longer a concern. Adjusting the voltage potential so that the switch operates in a saturation mode increases an effective capacitance across the switch and thereby retarding the power ramp-up across the switch.

In a first aspect, in a Primary Side Regulation (PSR) power supply, some primary current pulses are used to forward bias an output diode such that an auxiliary winding voltage can be properly sampled after each pulse. The samples are used to regulate the power supply output voltage (VOUT). Other primary current pulses, however, are of a smaller peak amplitude. These pulses are not used for VOUT regulation, but rather are used to determine whether the VOUT has dropped. In a second aspect, a transient current detector circuit within the PSR controller integrated circuit detects whether an optocoupler current has dropped in a predetermined way. If the TRS current detector detects that the optocoupler current has dropped, then the power supply stops operating in a sleep mode and is made to operate in another higher power operating mode in which the power supply switches.

The invention discloses a non-intrusive load identification method and a non-intrusive load identification device. The non-intrusive load identification method comprises steps that electricity utilization behavior habits of users are counted to acquire first data; an electricity utilization load standard characteristic database is established; a voltage discrete signal and a current discrete signal sampled on a power supply entrance are acquired; the acquired voltage discrete signal and the acquired current discrete signal are preprocessed; load characteristics are calculated according to the transient voltages corresponding to various sampling points in the voltage discrete signal of the power supply entrance and the transient currents corresponding to the various sampling points in the current discrete signal of the power supply entrance; the load identification is carried out according to the load characteristics, and second data is acquired; the weighting of the first data and the second data is carried out, and the type of the load is identified. The technical problem of the prior art of the low accuracy of the load identification during non-intrusive load monitoring is solved.

Apparatus and methods for detection of a ground fault on a DC side as well as on an AC side of an inverter are presented. A detection means can receive forward and reverse current and provide an induced current based on the difference between them. A parameter associated with the induced current, or a parameter associated with a voltage generated by conduction of the induced current through a device, can be used to detect a ground fault. In addition, a detection means can be configured to receive transient current, and a resulting voltage at the detection means can be used for fault detection. A detection means can be disposed at the DC side of an inverter or at the AC side of the inverter. Apparatus and methods can be configured to detect AC leakage current caused by a ground fault.

A wind turbine that includes a housing, an asynchronous generator disposed in the housing and configured to be electrically connected to a power grid connection; a power converter circuit disposed in the housing and configured to be electrically connected to the asynchronous generator; and a variable impedance device disposed in the housing, connected to the generator and configured to limit current by varying impedance in response to a transient current. The wind turbine delivers reactive power to the power grid when the variable impedance device varies impedance in response to the transient current. The variable impedance device can be arranged in series between the asynchronous generator and the power grid connection, or can be in a shunt arrangement between the asynchronous generator and a neural point.