13 results about "Overvoltage" patented technology

A safe power supply circuit of the invention comprises a single-chip microcomputer control circuit, a loop protecting circuit and a voltage reducing and stabilizing power supply circuit which supplies electric power to the single-chip microcomputer control circuit. The output end of the loop protecting circuit is connected with a voltage detecting circuit. One end of the output end of the voltage detecting circuit is connected with the single-chip microcomputer control circuit, and the other end is connected with a loop switch protecting circuit. The output end of the loop switch protecting circuit is connected with a current detecting circuit. The output end of the current detecting circuit is connected with the single-chip microcomputer control circuit. The output end of the single-chip microcomputer control circuit is connected with a voltage detecting circuit. The safe power supply circuit can settle the problems of no protecting measures for overvoltage, overcurrent and reverse charging; and incapability of realizing automatic matching between a charger and an anode and a cathode of a battery. Higher safety and higher user-friendly performance of an electric vehicle are realized.

The invention relates to a system and method for evaluating the voltage-sensitive characteristic of a lightning arrester valve plate under multiple lightning strokes, and belongs to the technical field of lightning arrester performance evaluation. A lightning arrester valve plate is arranged in a test box, and two metal electrodes are arranged on the upper portion and the lower portion of the valve plate; the output end of a multi-impulse current generator is connected to a first metal electrode, and a second metal electrode is connected with the grounding device; a temperature and humidity sensor is further arranged in the test box and can measure the temperature and humidity conditions of the test; a current sensor sleeves a current injection lead to measure the amplitude of the multi-impact current and the time when the waveform of the multi-impact current reaches the maximum value; two input ends of a high-voltage probe are respectively connected with the first metal electrode and the second metal electrode to measure the overvoltage amplitude of the lightning arrester valve plate; and in combination with the measured data, a voltage-sensitive characteristic evaluation factor of the lightning arrester valve plate is calculated, and the voltage-sensitive characteristic of the lightning arrester is evaluted. According to the invention, accurate control of multi-impulse current waveforms is realized, and the accuracy of voltage-sensitive characteristic evaluation of the lightning arrester valve plate under the action of multiple lightning strokes is improved.

A system and method for mitigating overvoltage on a DC link of a power converter of an electrical power system connected to a power grid includes receiving a voltage feedback signal from the DC link for a predetermined time period. The method also includes determining a rate of change of the voltage feedback signal during the predetermined time period. Further, the method includes predicting a future voltage value on the DC link as a function of the voltage feedback signal and the rate of change of the voltage feedback signal. Moreover, the method includes controlling the electrical power system based on the future voltage value.

The invention discloses an automatic overvoltage adjustment and protection device. The automatic overvoltage adjustment and protection device comprises a wire and a cross arm, wherein an adjustment rod is fixedly arranged on an installation plate at one side of the cross arm, the adjustment rod sleeves a sleeve at the bottom of the insulator body, a protection device is arranged at the top of theother side of the cross arm and is matched with the insulator body, the protection device comprises a wiring spherical electrode, a grounding spherical electrode and a parallel gap, the parallel gap is arranged between the wiring spherical electrode and the grounding spherical electrode, the wiring spherical electrode is arranged on an upper fixed fitting, the upper fixed fitting is fixedly arranged on the wire, the grounding spherical electrode is fixedly arranged on a lower fixed fitting and communicates with a current limiting component, an adjustment sleeve at the bottom of the current limiting component sleeves an outer side of a support rod, the bottom of the support rod is welded onto a sliding block, and the sliding block is connected with a sliding groove in the top of the cross arm in a sliding way. By the automatic overvoltage adjustment and protection device, an insulator can be effectively protected, the service lifetime of the insulator is prolonged, and the reclosing success rate of a circuit also can be improved.

The invention relates to the technical field of power protection and discloses an overvoltage control terminal and a distributed management system and method based on equal potential. The overvoltagecontrol terminal comprises an overvoltage control module, a discharge monitoring module, a fatigue monitoring module, a self-disengagement module, and a communication module. The overvoltage control terminal realizes voltage monitoring and management. The overvoltage control terminal distributed arrangement based on equal potential realizes the overall control and protection of the power supply and consumption equipment under the equal potential of a power supply network. The management system realizes visualized and centralized monitoring and management of the overvoltage control terminal ofthe entire power supply and consumption network, and has a high practical value and broad application prospects.

The invention provides an overvoltage protection method, an overvoltage protection circuit and a wireless charging system. The overvoltage protection method comprises the following steps that: an output voltage output by a rectifying circuit in a wireless charging system is monitored; if the output voltage exceeds a preset first overvoltage voltage threshold value and the duration of such as stateexceeds a preset first time threshold value, the positive half-bridge circuit of the rectifying circuit is switched off, and the negative half-bridge circuit of the rectifying circuit is switched on,so that a resonance electric energy signal output by a resonance circuit in the wireless charging system is discharged through a loop formed by the switched-on negative half-bridge circuit. And therefore, the operation reliability of the wireless charging system can be effectively improved.

The invention discloses a power supply screen input comprehensive test board characterized by comprising a first power supply input end Uin1, a second power supply voltage input end Uin2, a first power supply output end Uout1 and a second power supply output end Uout2; the first power supply input end Uin1 and the second power supply voltage input end Uin2 are used for being connected with an external power grid; and the first power supply output end Uout1 and the second power supply output end Uout2 are used for connecting a first path power supply input end and a second path power supply input end of a power supply screen, wherein the first power supply input end Uin1 is provided with a firing wire end which is sequentially connected with a three-phase circuit breaker QF11, an automaticvoltage regulator TYQ1, a three-phase circuit breaker QF12 and a contactor KM11; and the second power supply input end Uin2 has a firing wire end which is sequentially connected with a three-phase circuit breaker QF21, a manual voltage regulator TYQ2, a three-phase circuit breaker QF22 and a contactor KM21. According to the invention, the detection functions of overvoltage, undervoltage, phase dislocation and phase loss of the input power supply of the power supply screen can be realized through different functional modules, and the test board has important practical significance.