1017 results about "Arc suppression" patented technology

A plasma reactor for processing a semiconductor workpiece, includes a reactor chamber having a chamber wall and containing a workpiece support for holding the semiconductor support, the electrode comprising a portion of the chamber wall, an RF power generator for supplying power at a frequency of the generator to the overhead electrode and capable of maintaining a plasma within the chamber at a desired plasma ion density level. The overhead electrode has a capacitance such that the overhead electrode and the plasma formed in the chamber at the desired plasma ion density resonate together at an electrode-plasma resonant frequency, the frequency of the generator being at least near the electrode-plasma resonant frequency. The reactor further includes a set of MERIE magnets surrounding the plasma process area overlying the wafer surface that produce a slowly circulating magnetic field which stirs the plasma to improve plasma ion density distribution uniformity.

The invention discloses a distributing net single phase earth fault type and a distinguishing method of phase identification, relating to a distributing net single phase earth fault distinguishing method in the field of AC distributing net testing and relaying protection technology. According to the invention, through collecting three-phase voltage of the distributing net system and neutral point voltage of the distributing net system, phase angle of each eigenvector is computed through a special relation, the type of the fault and the phase identification can be fast distinguished through the phase angle distinguishing logic. The inventive working system is that a three-phase bus (000), a grounding transformer (100), a linear side of an arc suppression coil (200) are connected in turn with the earth; a controller (400), a thyristor (300) and a secondary side of an arc suppression coil (200) are connected in turn. The invention is simple in criterion, small in collection quantity, fast in distinguishing speed, high in accuracy, reliable in security, which is suitable for 3-66 KV distributing net based on an aerial line or a power cable.

The invention relates to a distribution network ground fault arc suppression method based on three-phase cascade H bridge converters. The three-phase cascade H bridge converters are adopted to replace arc suppression coils and mounted between phase lines and the ground, and power is supplied to capacitors on the direct current side of the converters by using phase voltages, so that boosting transformers and grounding transformers are saved, and the problem of source taking difficulty on the direct current side of the converters is solved. The converters inject current to a distribution network in a phase splitting mode to compensate the total current of a ground fault to be zero or to inhibit the phase voltage of the fault to be zero, so that the arc is automatically extinguished; and the reference compensation current is calculated by using real-time measured zero sequence voltage, so that the fault phase identification link is saved. The operation is simplified by using the voltage arc suppression method of controlling the zero sequence voltage to adjust the injected compensation current. In view of the influence of circuit parameters and load current on the arc suppression effect and the deduced relation between the ground fault residual current after the voltage arc suppression method is applied and the zero sequence voltage after the fault, an adaptive arc suppression method is put forward by using the zero sequence voltage as a voltage and current arc suppression method.

The invention discloses a new method for performing fault line selection by using the characteristic of a non-power frequency transient state fault component for extracting single-phase fault zero-sequence current by using Hilbert-Huang transform (HHT). The method comprises the following steps: performing EMD decomposition on fault zero-sequence current of each feeder line by using the HHT to acquire an IMF component of the zero-sequence current of each feeder line; constructing a resolving signal according to Hilbert transform, solving instantaneous amplitude and frequency of the zero-sequence current of each feeder line, and eliminating a power frequency component in the instantaneous frequency of the zero-sequence current of each feeder line to acquire a non-power frequency fault component; and forming a line selection criterion according to the characteristics that the amplitude of the non-power frequency fault component of the fault line is greater than that of the non-fault line and the polarity of the fault line is opposite to that of the non-fault line. The line selection method is not affected by an arc suppression coil, and is applicable to non-grounded, arc suppression coil grounded and high-resistor grounded systems, overhead lines or cable lines and cable overhead mixed lines; and the line selection result shows that the method applied to low-current single-phase grounding fault line selection is accurate and reliable.

A two terminal arc suppressor for protecting switch, relay or contactor contacts and the like comprises a two terminal module adapted to be attached in parallel with the contacts to be protected and including a circuit for deriving an operating voltage upon the transitioning of the switch, relay or contactor contacts from a closed to an open disposition, the power being rectified and the resulting DC signal used to trigger a power triac switch via an optoisolator circuit whereby arc suppression pulses are generated for short predetermined intervals only at a transition of the mechanical switch, relay or contactor contacts from an closed to an open transition and, again, at an open to a close transition during contact bounce conditions.

The invention relates to a detection system and a detection method for single-phase grounding fault line selection in a small current grounding system. The system comprises a load switching device and a small current grounding line selection device, the load switching device comprises a load, a switching switch, a controller and a sampling device, the load is connected with the switching switch in series and further connected with an arc suppression coil in parallel, and the controller is respectively connected with the switching switch and the sampling device; the small current grounding line selection device is connected with each circuit in the small current grounding system, and the small current grounding line selection device is further connected with the controller in the load switching device. The system and the method can effectively solve the problem of difficulty in line selection of single-phase grounding fault in the small current grounding system, and improve the accuracy of line selection.

A system is presented. The system includes a first micro-electromechanical system switch. Further, the system includes arc suppression circuitry coupled to the first micro-electromechanical system switch, wherein the arc suppression circuitry comprises a balanced diode bridge and is configured to facilitate suppression of an arc formation between contacts of the first micro-electromechanical system switch.

The invention discloses an intelligent dynamic power distribution network neutral-point grounding method and a complete device. The complete device comprises a grounding transformer (1), an arc suppression loop switch (2), a resistance loop switch (3), an adjustable reactor (4), a damping resistor (5), a damping resistor short-circuit switch (6), a resistor (7), a neutral-point voltage transformer (8) and a computer testing and control system (9). The intelligent dynamic power distribution network neutral-point grounding method and the complete device is technically characterized in that a power distribution network neutral-point grounding mode is dynamically converted from an arc suppression coil grounding mode into a small-resistance grounding mode. When the device is connected to a power grid or a power grid operation mode changes, the device firstly works in the arc suppression coil grounding mode. The device measures capacitive current, adjusts inductive current and enables IL-IC to be smaller than or equal to I delta, wherein the I delta is a preset residual current control value. When a single-phase grounding fault of the power grid occurs, the device outputs the inductive current to perform compensation and arc suppression to grounding fault current. If the fault is an instantaneous fault, the fault is eliminated through the compensation and the arc suppression. If the fault is a permanent fault and the grounding fault is still not eliminated after certain time T, the arc suppression coil grounding is converted into the resistance grounding mode, and a fault line is judged and disconnected by detecting zero-sequence current of feeder lines.

Arc suppression systems, devices and methods for avoiding undesirable arcing conditions inside a liquid-filled tank of a high-voltage electrical apparatus.

A method for achieving single-phase earth fault line selection of a small current grounding system is characterized in that a high-precision zero-sequence current transformer is adopted by each feeder line; a single-phase earth fault of the system is confirmed when the instantaneous value of the zero-sequence current i0 of any one feeder line exceeds a set threshold /I0 /; comparison is conducted on symbols of all loop circuits at the moment of threshold triggering, and data after the triggering do not participate in judgment; the symbol of a faulty line current is unique and opposite to the symbols of non-faulty line currents, and the number of non-faulty lines is larger than or equal to 2; when the symbols of all the currents are identical, a bus earth fault is confirmed. The method for achieving single-phase earth fault line selection of the small current grounding system is adaptable to three grounding modes, namely neutral non-grounding, arc suppression coil grounding and neutral point high resistance grounding, of the small current grounding system and is not affected by a grounding moment phase angle, system unreal grounding and TV disconnection, and correction operation can still be achieved when the zero-sequence voltage of a bus is reduced to be 10% of a phase voltage by a transition resistor.

The invention discloses a ground fault fully compensated controllable voltage source output voltage computing method, comprising the steps of obtaining circuit ground capacitance, leakage resistance,fault ground resistance, arc suppression coil inductance, resistance and controllable voltage source internal resistance when a ground fault occurs; computing parallel impedance of a circuit ground parameter and a compensation inductance parameter according to the arc suppression coil inductance, the resistance, the leakage resistance and the circuit ground capacitance; and computing a controllable voltage source output voltage according to the fault ground resistance, the controllable voltage source internal resistance and the parallel impedance of the circuit ground parameter and the compensation inductance parameter. According to the method, in a voltage source access mode, the state problem that an arc suppression coil inductance parameter and the circuit ground capacitance approximateto power frequency resonance does not need to be taken into consideration; control is relatively easy; a fault current can be effectively compensated; and arc quenching is carried out on a fault point. According to the method, phase and amplitude of the output voltage are obtained through computing, the current at the fault point is quenched through control over the phase and amplitude of a controllable voltage source, and safe and stable operation of a power grid is ensured.

A power distribution network one-phase grounding fault location method based on a zero sequence voltage belongs to a power distribution network grounding fault location method. The fault location method starts from an overall zero sequence parameter of a single-end radial medium voltage power distribution network, analyzes a one-phase grounding fault while taking a distributed parameter model influence into consideration, measures a steady-state zero sequence voltage value and a zero sequence current of each feeder line at a bus position and at a tail end of each outlet line, and finds zero sequence voltage variation characteristics of a fault feeder line and non-fault feeder line. According to the invention, a large number of existing devices are used, the data sampling requirement is low in terms of being real-time, and the method of the invention is easy to realize; the simulation model analysis is established according to the actual parameters, so that the fault location can be realized in the system in which the neutral point is not grounded or the neutral point is grounded through an arc suppression coil; the precision is quite high; and the location method of the invention can be applied to the medium and low voltage power distribution network.

The invention provides a power distribution network single-phase earth fault section locating method based on correlation analysis. The fault line selection problem in the single-phase earth fault process of a power distribution network is not solved well, and fault locating is more difficult to refer to. After a single-phase earth fault happens to a system, the first capacitive frequency band concept is utilized, each line is simplified into a capacitance model in a zero-sequence network under the selected frequency band, earth fault detection devices are arranged on line outlets and branches to measure zero-sequence voltages and zero-sequence currents, association coefficients of zero-sequence voltage differentials and the zero-sequence currents are obtained, whether fault points are in the section or not is judged according to plus and minus of the obtained association coefficients, finally the association coefficients are judged and calculated to be minus, and the section farthest away from a bus is the section where the fault points are located. The method is simple in principle and easy to implement, fault section locating can be carried out fast and reliably, and the method can be used for neutral ungrounding power distribution systems and can be used for power distribution systems with neutral points grounded through arc suppression coils.

The arc suppression system for electrical contacts includes a transistor, such as an IGBT, which is connected across the contacts. A control circuit controls the operation of the transistor such that the turning on of the transistor results in a current path around the contacts, thereby tending to prevent arcing across the contacts. A current sensor, such as a flyback transformer, is positioned in series with the contacts, wherein when the contacts open, current is interrupted through the contacts and the transformer, a secondary voltage results which is applied to the transistor, which tends to maintain the transistor on for a time which is sufficient to allow the contacts to either open or close without an arc.

The invention discloses a diagnosis method for a single-phase line breakage grounding complex fault type of a power distribution network based on a zero sequence voltage, and the method comprises the steps: setting a start value of the zero sequence voltage through determining a small current grounding mode; extracting voltage sampling data of each phase of N cyclic waves before a line breakage moment and N cyclic waves after a fault moment, and calculating and obtaining the phase difference relation between the phase of the fault phase voltage before the fault and the phase of the steady-state zero sequence voltage after the fault and a reference function as the criterion through the FFT and a symmetrical component algorithm; judging whether the zero sequence voltage exceeds the start value or not: carrying out the extraction if the zero sequence voltage exceeds the start value and judging whether the phase difference between the phase of the zero sequence voltage and the phase of the fault phase voltage before the fault is corresponding to a load side grounding range of the criterion or not: determining that the fault is a single line breakage and load side grounding fault if the phase difference is corresponding to the load side grounding range of the criterion, or else determining that the fault is a single line breakage and power side grounding fault. The method is good in universality, and is suitable for power distribution networks at various voltage levels, wherein the neutral points of the power distribution networks are not grounded or the power distribution networks are grounded through arc suppression coils. Moreover, the deviation angle is not affected by the voltage level.

A circuit to suppress arc across contacts of a relay is provided, in which the relay is electrically coupled to a power supply and a load. The circuit includes an arc suppression circuit electrically coupled between the first and second contacts of the relay, and the arc suppression circuit includes a capacitor and a switch, both of which are electrically coupled to the first and second contacts of the relay, in which the switch is configured to turn on when the first and second contacts of the relay change state, thereby providing an alternate path for a current flow through the load.

An arc suppression circuit in a protection relay having trip contacts is used to turn off a battery-powered solenoid and trip an AC power circuit breaker. The arc suppression circuit uses a switch-control circuit to control the turning off of a semi-conductor switch so that the semi-conductor switch provides a current path around the trip contacts, and is carrying all, or substantially all, of the load current, before the trip contacts are opened. When the trip contacts begin to open, the switch-control circuit holds the semi-conductor switch on for a sufficient time to prevent an arc from becoming established before turning the semi-conductor switch off. In a second embodiment, the arc suppression circuit provides a second switch-control circuit. This second switch-control circuit is configured to accept control signals from a microprocessor within a protection relay. The microprocessor turns the semi-conductor switch on before the contacts begin to open, thereby providing a current path around the contacts before the contacts begin to open. The microprocessor turns the semi-conductor switch off after a time sufficient to prevent an arc from becoming established.