Abstract

The present invention relates to the technical field of resistors, in particular to a sandwich-type resistor, comprising a supporting module and a resistor unit. The resistor unit comprises a plurality of resistor pieces and a plurality of insulating partition pieces which are sequentially and alternately stacked, a transition hole is formed in each insulating partition piece at a position close to an end part, and a bent section is integrally formed at an end part of each resistor piece and passes through the corresponding transition hole to be connected to another resistor piece, such that the plurality of resistor pieces are electrically connected. The two side surfaces of each resistor piece are tightly attached to and covered with different insulating partition pieces, thus impurities such as dust will not fall on the surfaces of the resistor pieces, and the dustproof and anti-fouling grade is high. Since no deformation space is left in the arrangement direction of the resistor pieces, the resistor pieces, after being electrified, will not deform at all or even move close to each other, thereby having a stable structure and a good insulation property.

IPC Classes  ?

• H01C 1/02 - HousingEnclosingEmbeddingFilling the housing or enclosure
• H01C 1/08 - Cooling, heating or ventilating arrangements
• H01C 1/01 - MountingSupporting

Abstract

The present invention relates to the technical field of resistors, in particular to an anti-high current resistor, comprising string rods, multiple insulating separation rings, and multiple resistor sheets arranged in parallel. The string rods string the multiple insulating separation rings and the multiple resistor sheets; each separation ring is located between each two adjacent resistor sheets, such that the multiple resistor sheets are positioned at intervals; and the multiple resistor sheets are connected in series or in parallel. The resistor further comprises multiple insulating thermal conductive sheets arranged in parallel; the multiple thermal conductive sheets are respectively located between each two adjacent resistor sheets; the thermal conductive sheets are provided with receding holes for the string rods and the separation rings to penetrate through; the receding holes are in clearance fit with the separation rings; and the thickness of the thermal conductive sheets is smaller than the distance between two adjacent resistor sheets, such that the thermal conductive sheets can move between two adjacent resistor sheets along the arrangement direction. The two adjacent resistor sheets can be completely prevented from arcing and attracting, and the heat dissipation performance of the resistor sheets can be greatly improved.

IPC Classes  ?

• H01C 1/084 - Cooling, heating or ventilating arrangements using self-cooling, e.g. fins, heat sinks

Abstract

A tap water cooling bridge arm based on aluminum nitride. The tap water cooling bridge arm comprises a group of first semiconductor devices (11), a group of second semiconductor devices (12), and a group of third semiconductor devices (13), wherein a heat sink (3) is respectively arranged between each of the group of first semiconductor devices (11), the group of second semiconductor devices (12) and the group of third semiconductor devices (13) and an insulating block (2); the heat sink (3) comprises a copper shell (31); the copper shell is provided with a cavity; one end of the cooper shell is provided with an opening (34); an aluminum nitride shell (32) is arranged at the cavity and the opening (34); and a water cooling channel (33) is provided in the aluminum nitride shell (32). By means of arranging a copper shell (31) and an aluminum nitride shell (32), a heat dissipation requirement of a device can be met, and requirements for the conductivity performance and crimping strength can also be met; and by using the aluminum nitride shell (32), a cooling water flow channel of a bridge arm can be isolated from a conductive loop, and the insulating property of the aluminum nitride shell (32) itself can enable the bridge arm to have no conductivity requirement for cooling water any more, such that ordinary tap water can be introduced into the bridge arm for heat dissipation.

IPC Classes  ?

• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating

Abstract

A multifunctional self-checking switching-on power supply device, relating to the technical field of power supply devices, and comprising: a battery energy storage module (1), a boosting module (2), an inversion module (3), a control module (4), a transformer (5), a switch (6), a voltage transformer PT1, a voltage transformer PT2, and an amplitude and phase detection module (7). The controller (4) can automatically adjust the amplitude and phase output by the inversion module (3) until the amplitude and phase output by the inversion module are consistent with the amplitude and phase of an incoming line power grid of a switch cabinet, then a switch-on signal of the switch cabinet is sent out, and a circuit breaker of the switch cabinet starts to be closed. When a large-scale transformer (5) is started and switched on, a magnetic field having the same amplitude and the same phase as the incoming line power grid is first established, the surge current can be greatly reduced, and large excitation surge current impact on the power grid cannot be caused.

IPC Classes  ?

• H02J 3/42 - Synchronising a generator for connection to a network or to another generator with automatic parallel connection when synchronism is achieved
• H02H 9/00 - Emergency protective circuit arrangements for limiting excess current or voltage without disconnection

Abstract

A new secondary wire break protection apparatus for a current transformer, the apparatus comprising: a working power source, a first intermediate relay, a second intermediate relay, an alarm indicator lamp 1HL1, and a single-phase connection terminal and an N-phase connection terminal, which are connected to two ends of a secondary winding of a current transformer, wherein the first intermediate relay has a coil 1KA1, normally closed contact points 1KA11 and 1KA13, and normally open contact points 1KA12 and 1KA14; and the second intermediate relay has a coil 1KA2, a normally open contact point 1KA21, and a first normally open contact point, which is configured to be controlled to trigger an alarm signal. The signal-phase connection terminal sequentially connects, in series, 1KA11 and 1KA12 to an N-phase output end of the working power source; the N-phase connection terminal sequentially connects, in series, 1KA13 and 1KA14 to an L-phase output end of the working power source; one end of each of 1KA1 and 1KA2 is connected to a connection point between 1KA11 and 1KA12, and another end thereof is connected to a connection point between 1KA13 and 1KA14; and 1KA21 is connected across the signal-phase connection terminal and the N-phase connection terminal. By means of the present utility model, when an open circuit occurs in a secondary winding of a current transformer, the secondary winding can be automatically short-circuited while an alarm is automatically raised, such that the current transformer remains in a normal working condition.

IPC Classes  ?

• H02H 7/04 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for transformers
• H02H 7/00 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
• H02H 3/20 - Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition, with or without subsequent reconnection responsive to excess voltage
• H02H 9/04 - Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess voltage

Abstract

The present invention relates to a hybrid circuit breaker based on line inductance energy self-measurement, and a storage medium thereof and a control method therefor. The method comprises: when a hybrid circuit breaker receives a pull-in instruction, controlling a solid-state switch, which serves as a current transfer branch, in the hybrid circuit breaker to be turned on; and at the beginning of the pull-in of the current transfer branch, measuring line inductance energy W of a main loop where the hybrid circuit breaker is located, and if the line inductance energy W exceeds a first set threshold value, controlling the current transfer branch to be turned off and terminating turn-on control logic of the hybrid circuit breaker, otherwise, controlling a mechanical switch, which serves as a main through-flow branch, in the hybrid circuit breaker to be turned on, and turning off the current transfer branch after the main through-flow branch is completely pulled in. By means of the present invention, a line inductance energy protection mode is added on the basis of a traditional hybrid circuit breaker protection mode, such that not only is the usage range of a hybrid circuit breaker expanded, but the adaptability of the hybrid circuit breaker is also enhanced without increasing the cost.

IPC Classes  ?

• H02H 7/22 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for distribution gear, e.g. bus-bar systemsEmergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for switching devices
• H01H 9/54 - Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
• H01H 47/00 - Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current

Abstract

The present invention relates to an improved grounding transformer doubling as a station transformer, comprising: a grounding transformer secondary side; and a grounding transformer primary side comprising six primary side windings A1, A2, B1, B2, C1, and C2 that are wound on a three-phase core. Two of the primary side windings are distributed on each core column of the three-phase core, and the two primary side windings have an equal number of turns; the six primary side windings are wired in a Z-connection mode; the topological structure of the grounding transformer secondary side and the topological structure of the grounding transformer primary side are the same and are symmetrical to each other. According to the present invention, formulas I, II, and III of low-voltage output phase voltage vectors can successively be in phase with formulas IV, V, and VI of phase voltage vectors of high-voltage input side power grid voltage, respectively.

IPC Classes  ?

• H01F 27/30 - Fastening or clamping coils, windings, or parts thereof togetherFastening or mounting coils or windings on core, casing, or other support

Abstract

A switching transistor parallel current sharing verification device. A positive electrode of a detection power supply is connected to one end of a capacitor C1 by means of a pre-charge resistor R1 and an electric control switch RS, and the other end of the capacitor C1 is connected to a negative electrode of the detection power supply. The capacitor C1 is configured to connect a plurality of external IGBT/MOS transistors in parallel to each other, wherein each IGBT/MOS transistor parallel branch is configured with a current sensor for acquiring current of the branch. The current sensors are respectively connected to ADC channels of an ADC acquisition module. The ADC acquisition module has the capability of synchronous acquisition by the plurality of ADC channels. A controller is connected to a controlled end of the electric control switch RS and the ADC acquisition module. The switching transistor parallel current sharing verification device can verify whether parallel IGBT/MOS transistors meet a current sharing requirement after being assembled.

IPC Classes  ?

• G01R 31/28 - Testing of electronic circuits, e.g. by signal tracer
• G01R 19/25 - Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques

Abstract

A power grid single phase-to-ground fault simulation load device, comprising: three phase selection contactors S1-S3, one ends of the three phase selection contactors being respectively connected to a high-voltage three-phase inlet wire of an external active intervention type arc suppression device, and the other ends of the three phase selection contactors being connected together to form a contact J; a zero-sequence current sampling sensor for collecting a zero-sequence current at the contact J; a zero-sequence voltage sampling sensor for collecting a zero-sequence voltage at the contact J; at least seven analog grounding resistors R1-R7 having different resistance values, each analog grounding resistor having one end grounded, and the other end jointly connected to the contact J by means of a high-voltage vacuum contactor; and a remote communication unit module comprising a power supply, a single-chip microcomputer controller, and a remote communication interface, the single-chip microcomputer controller obtaining electricity from the power supply, remotely communicating with an external remote control center by means of the remote communication interface, and being respectively connected to the zero-sequence current sampling sensor, the zero-sequence voltage sampling sensor, and controlled ends of the contactors.

IPC Classes  ?

• G01R 31/08 - Locating faults in cables, transmission lines, or networks

Abstract

A compact vehicle-mounted direct-current deicing power supply, comprising a housing (1), an air-cooling heat dissipation assembly, and at least two three-phase uncontrollable rectifier bridges (3). The housing (1) is internally provided with an air channel partition plate (2) for dividing the inner space of the housing (1) into an upper layer and a lower layer; the three-phase uncontrollable rectifier bridges (3) are mounted on the air channel partition plate (2) in parallel, and the input and output ends of the three-phase uncontrollable rectifier bridges (3) extend out of the housing (1) by means of wall bushings (4); the air-cooling heat dissipation assembly is provided with an air feeder and at least two exhaust fans, the air feeder is mounted on the bottom surface of the air channel partition plate (2), ventilation air channels communicated with the outside are provided in the side walls of the housing (1) in both the upper-layer space and the lower-layer space, and the exhaust fans are respectively arranged on the side walls of the housing (1) in the upper-layer space and communicated with the ventilation air channel in the upper-layer space. The interior of the device is divided into an upper layer and a lower layer, forced air cooling type heat dissipation is adopted, cold air enters from the lower portion and is discharged from upper air outlets on the left side and the right side, normal heat dissipation and stable work are ensured, and the device is compact in overall structure, small in size and convenient to carry and move on a vehicle.

IPC Classes  ?

• H02G 7/16 - Devices for removing snow or ice from lines or cables

Abstract

The present invention relates to the technical field of pre-magnetizing apparatuses, and in particular to a pre-magnetizing apparatus for a power supply transformer. The pre-magnetizing apparatus comprises a main power supply source (1), a power supply transformer, a pre-magnetizing mechanism and a load end (2), wherein the power supply transformer comprises a primary side and a secondary side; the main power supply source (1) is connected to the primary side; the secondary side is connected to the load end (2) by means of the pre-magnetizing mechanism; the pre-magnetizing mechanism comprises a low-voltage current-limiting resistor (R1), a low-voltage contactor (S1) and a three-phase AC power source (3); and the three-phase AC power source (3) is connected between the secondary side and the load end (2) by means of the low-voltage current-limiting resistor (R1) and the low-voltage contactor (S1). By means of performing pre-magnetization at a secondary side of a power supply transformer, a low-voltage device, which can easily be purchased and has a low cost, can be used in a magnetizing loop. In a pre-magnetization solution, current limiting is performed at a secondary side of a power supply transformer by using a low-voltage current-limiting resistor (R1), such that the cost is low, and an isolation effect is also achieved between a loop power source of the power supply transformer and a three-phase AC power source (3), thereby reducing the mutual influence between the two loop power sources.

IPC Classes  ?

• H01F 13/00 - Apparatus or processes for magnetising or demagnetising
• H01F 27/34 - Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
• H02H 9/00 - Emergency protective circuit arrangements for limiting excess current or voltage without disconnection

Abstract

The present invention relates to a power distribution network grounding fault step-down active arc extinction power supply and a control method therefor. The active arc extinction power supply comprises a step-up transformer T2, a four-quadrant conversion power module, a series transformer T1, a three-phase alternating-current power supply, an output filter and three phase selection switches, wherein two outgoing line ends of a secondary side of the step-up transformer T2 are respectively connected to a neutral point of a primary side of a grounding transformer Tz in a power distribution network, and the ground; an a-phase output end, a b-phase output end and a c-phase output end of the three-phase alternating-current power supply are respectively connected in series to a phase selection switch and are then connected together to form a contact J; the contact J is connected to one outgoing line end of a primary side of the step-up transformer T2 after passing through a secondary winding of the transformer, and the other outgoing line end of the primary side of the step-up transformer T2 is connected to an n-phase output end of the three-phase alternating-current power supply; the four-quadrant conversion power module comprises a three-phase PWM rectifier, a supporting capacitor C4 and a single-phase inverter; the three-phase PWM rectifier obtains power from the three-phase alternating-current power supply, and a direct-current side of the three-phase PWM rectifier is in bridge connection with the supporting capacitor C4 and is then connected to the single-phase inverter; and an output of the single-phase inverter is loaded to two ends of a primary side of the transformer T1 by means of the output filter.

IPC Classes  ?

• H02H 9/08 - Limitation or suppression of earth fault currents, e.g. Petersen coil
• H02M 5/458 - Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into DC by static converters using discharge tubes or semiconductor devices to convert the intermediate DC into AC using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
• H02M 5/45 - Conversion of AC power input into AC power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into DC by static converters using discharge tubes or semiconductor devices to convert the intermediate DC into AC using devices of a thyratron or thyristor type requiring extinguishing means using semiconductor devices only
• H02M 1/12 - Arrangements for reducing harmonics from AC input or output
• H02M 1/14 - Arrangements for reducing ripples from DC input or output

Abstract

The present utility model relates to a processing apparatus for output excitation of a grid-connected converter. The processing apparatus comprises an input port, an output port, a current-limiting resistor R, a timing apparatus T, a normally-on electric control switch K, and a filter capacitor C. The input port is connected to the output port separately via the current-limiting resistor R, the normally-on electric control switch K, and the filter capacitor C, and the current-limiting resistor R, the normally-on electric control switch K, and the filter capacitor C are connected in parallel. The timing apparatus T is used for performing timing control on the normally-on electric control switch K so as to turn on and off. The processing apparatus of the present utility model solves the problem of overcurrent caused by magnetic saturation of an output excitation transformer or a large generator due to excessive instantaneous output current. Moreover, the processing apparatus has a simple structure, and is low-cost and easy to use.

IPC Classes  ?

• H02H 9/02 - Emergency protective circuit arrangements for limiting excess current or voltage without disconnection responsive to excess current
• H02P 9/10 - Control effected upon generator excitation circuit to reduce harmful effects of overloads or transients, e.g. sudden application of load, sudden removal of load, sudden change of load

Abstract

The present utility model relates to a low-voltage hybrid direct-current circuit breaker, comprising a main through-flow branch, a current transfer branch, an energy absorption branch and a control device. The main through-flow branch is provided with a wiring terminal Port1, a fuse F1, a fast mechanical switch S1, a current-limiting inductor L1, and a wiring terminal Port2 which are sequentially connected in series, and a current detection sensor Am1 for detecting a current of the fast mechanical switch S1 and a current detection sensor Am2 for detecting the total current of the main through-flow branch. The current transfer branch and the energy absorption branch are connected in parallel to the two ends of the fast mechanical switch S1. The control device is used for receiving electrical parameters of the current detection sensors and controlling the on-off of the fast mechanical switch S1 and the current transfer branch. According to the present utility model, a sharp rise of a short-circuit current can be effectively prevented, so that the current detection devices and the control device have enough response time, and effective disconnection can be achieved under the condition that a control system fails or a main contact is adhered, thereby preventing accidents from being further expanded.

IPC Classes  ?

• H01H 9/54 - Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
• H02H 3/087 - Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition, with or without subsequent reconnection responsive to excess current for DC applications

Abstract

A direct current de-icing device, comprising a CPU and six groups of switch blocks. The six groups of switch blocks constitute a three-phase PWM rectifying structure; three-phase input ends of the three-phase PWM rectifying structure are respectively connected in series to three inductors (L1, L2, L3) and then are used for connecting external 14 kV three-phase electrical power; output ends of the three-phase PWM rectifying structure are used for connecting an external transmission circuit; each group of switch block is formed by connecting a plurality of power transistors in series according to a same conduction direction; E and C poles of each power transistor are in bridge connection to resistors (R2) having the same resistance value; the number of power transistors in each group of switch block is the same; the CPU is separately connected to G electrodes of the power transistors for control. When an input voltage is fixed, the direct current de-icing device may regulate and control, by means of software, to output different voltages so as to satisfy the requirements of a user for quickly de-icing or slowing down speed by regulation.

IPC Classes  ?

• H02G 7/16 - Devices for removing snow or ice from lines or cables
• H02M 7/219 - Conversion of AC power input into DC power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only in a bridge configuration

Abstract

The present invention relates to the technical field of copper bars, and in particular to a copper bar manufacturing method and a copper bar structure. The method comprises the following steps: a step of material selection, which comprises: preparing a copper pipe with a radial cross-sectional area being a preset value, and determining a position for bending the copper pipe; a step of bending, which comprises: bending the copper pipe from the position for bending according to a preset angle, so as to form a bent pipe; and a step of flattening, which comprises: flattening the bent pipe in a radial direction to form a flat copper bar. The manner of first bending and then flattening the copper pipe is used, such that the copper pipe is convenient to bend and less prone to tearing than a traditional copper plate, and copper bars in various bent shapes can be manufactured according to requirements, thereby reducing the cost. A copper bar structure manufactured according to the method has a double-layer plate body structure, high strength and a stable structure.

IPC Classes  ?

• H01B 5/02 - Single bars, rods, wires or stripsBus-bars

Abstract

The present invention relates to the technical field of loads, and particularly relates to a band-type resistor having large current surge resistance, which comprises side plates and a plurality of resistor units. Each resistor unit comprises a plurality of resistor sheets arranged in parallel and string rods which connect the plurality of resistor sheets in series; two ends of each string rod are respectively fixed to the two side plates; the string rod strings have a plurality of insulating seats for separating two adjacent resistor sheets; a protrusion extending in an axial direction is formed on each insulating seat; the resistor sheets are fitted outside the protrusions; reinforcing ribs are provided at the middle of each resistor sheet; mica partition plates are further arranged between the two side plates; each mica partition plate is located between two adjacent resistor units; a plurality of limiting slots are formed on the two sides of each mica partition plate, respectively; the side portions of the resistor sheets of the two adjacent resistor units are embedded into the limiting slots; slot walls of the limiting slots abut against the reinforcing ribs of the resistor sheets. In a use process, even if the resistor sheets are subjected to a tendency to deform due to a large current surge, the mica partition plates can also hinder the deformation of the resistor sheets, thereby avoiding a breakdown fault.

IPC Classes  ?

• H01C 13/02 - Structural combinations of resistors
• H01C 1/16 - Resistor networks not otherwise provided for
• H01C 1/014 - MountingSupporting the resistor being suspended between, and being supported by, two supporting sections
• H01C 1/01 - MountingSupporting

Abstract

The present utility model relates to the technical field of resistors, and relates in particular to an active load regulation resistor, which comprises a plurality of arranged resistor towers, the number of rows thereof being more than two rows. A plurality of sets of bridge assemblies are disposed between two adjacent rows of resistor towers. Each set of bridge assemblies comprises an uprightly arranged column, a cross beam that is fixed to the column, and a first insulator that is erect on the cross beam. A top portion of the first insulator is provided with a conductive seat. The bridge assembly further comprises a tube bus, and the conductive seats of each set of bridge assemblies are electrically connected by means of the tube bus. Lead-out terminals of different resistor towers are electrically connected to one another and then electrically connected to the conductive seats of the bridge assemblies. In comparison with the existing technology, the overall layout is reasonable and resistor boxes stacked in the resistor towers occupy a relatively small area; in addition, by connecting to the conductive seats of the bridge assemblies by means of the lead-out terminals, when a particular resistor tower fails, maintenance can be carried out by disconnecting the current of a corresponding lead-out terminal, and therefore the maintenance operation is convenient and suitable for an electronic load power balance system of a regional power grid.

IPC Classes  ?

• H01C 1/16 - Resistor networks not otherwise provided for
• H01C 13/02 - Structural combinations of resistors
• H01C 1/022 - HousingEnclosingEmbeddingFilling the housing or enclosure the housing or enclosure being openable or separable from the resistive element
• H01C 1/01 - MountingSupporting
• H01C 1/014 - MountingSupporting the resistor being suspended between, and being supported by, two supporting sections
• H01C 1/14 - Terminals or tapping points specially adapted for resistorsArrangements of terminals or tapping points on resistors
• H02J 3/26 - Arrangements for eliminating or reducing asymmetry in polyphase networks
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers
• H02J 3/18 - Arrangements for adjusting, eliminating or compensating reactive power in networks