CN2272161Y

CN2272161Y - Remote interphase short-circuit protection

Info

Publication number: CN2272161Y
Application number: CN 96223998
Authority: CN
Inventors: 杨运富; 杨玉生; 杨广勤
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-10-29
Filing date: 1996-10-29
Publication date: 1998-01-07
Anticipated expiration: 2006-10-29

Abstract

The utility model relates to a remote interphase short circuit protector, which is characterized in that a terminal voltage detection device and a starting terminal electric leakage detection device are separately arranged in a detected electrical network. The terminal voltage detection device is formed by that a voltage detection transformer is respectively arranged on each interphase of the load side of the detected electrical network, so a power distribution system is in an electrical leakage state when the phase fault exists. The starting terminal device is used for detected the electrical leakage of the power distribution system, and is used for the final control of the breaking of an electrical distribution switch. The utility model can carry out reliable remote detection for phase fault and implement the protection.

Description

Distant phase fault protector

The utility model relates to the phase fault protective device, more particularly, is a kind of Distant phase fault protector that can implement short-circuit protection to distribution system middle and long distance end.

In the prior art, no matter be conventional current sampling short-circuit protection, or the Quick short-circuit protection in the patented technology, all be according to the current sample short-circuit signal.But under coal mine; because the getting working face power supply distance is long; terminal short circuit current is little; and big electric motor starting electric current is big, and is similar with short-circuit current value, therefore; GPF (General Protection False device in the panel switches is restricted on guard space; phase fault often, the panel switches tripping can cause gas, coal-dust explosion and fire.

The purpose of this utility model is to avoid above-mentioned the deficiencies in the prior art part, and providing a kind of can detect remote phase fault reliably, and implements the Distant phase fault protector of protection.

The purpose of this utility model is achieved through the following technical solutions.

The utility model is that end voltage checkout gear and top earth detector are set respectively in tested electrical network; Described end voltage checkout gear is each alternate voltage detecting transformer TV1, TV2, TV3 or the optocoupler voltage sensor of being provided with respectively of load side at tested electrical network, the secondary end output of described transformer TV1, TV2, TV3 is connected to the circuit of adjusting of comparator IC1-1, IC1-2 and IC1-3 formation respectively, and pass through comparator IC1-4 to switching tube V20, the coil of relay K A2 is arranged on switching tube V20 collector electrode, simultaneously, the normally-closed contact of relay K A2 is connected across between arbitrary phase line of electrical network and the ground wire; Described top earth detector is the pseudo-central point testing circuit that is made of R35, R36, R37, V12, V13, V14 in the setting of tested electric network source side, and it detects output and exports the switch actuator part to via the circuit of adjusting that comparator IC2-1, IC2-2, IC2-3 and IC2-4 constitute.

Compared with the prior art, the utility model is according to the voltage sample short-circuit signal.The terminal installation of implementing voltage detecting is connected the end of protected distribution system; short dot is inevitable all to be occurred in before the terminal installation; obviously; two phase voltages after the short dot are zero or minimum residual voltage; terminal installation with the short-circuit signal of voltage detecting through relatively output; make distribution system be in the electric leakage state, in panel switches, be provided with in order to detect the top device of leak resistance value simultaneously.When the top device between terminal installation during three-phase power line any point generation phase fault, terminal installation detects zero volt voltage, so the top device detects electric leakage signal, and forces the panel switches disjunction, plays a protective role.Compared with the prior art, the utility model reliable operation, being low to moderate rated voltage at line voltage all can operate as normal more than 50%.Simultaneously, the utility model has wide range of applications, and can generally be applicable in 6000V, 1140V, 660V, the 380V distribution system, the length in 127V electricity coal borer and the light distribution system is apart from the latter end circuit.

Accompanying drawing 1 is the utility model end voltage checkout gear circuit theory diagrams.

Accompanying drawing 2 is the utility model optocoupler voltage sensor circuit theory diagrams.

Accompanying drawing 3 is the utility model top earth detector circuit theory diagrams.

By the following examples, in conjunction with the accompanying drawings, the utility model is made further indefiniteness describe.

Embodiment:

Referring to accompanying drawing, end voltage checkout gear (Fig. 1) and top earth detector (Fig. 3) are set respectively in tested electrical network.As shown in Figure 1, its end voltage checkout gear is with voltage detecting transformer TV1, TV2 and TV3 and rectifying and wave-filtering element VC2, VC4, VC5, C6, C8, C9, R8, R9, R10 forms voltage detection unit, voltage detecting transformer TV1, TV2, TV3 elementary is connected across tested network load side respectively, and each is alternate, its secondary end output becomes d. c. voltage signal through rectifying and wave-filtering with alternating voltage, output is respectively to comparator IC1-1, the circuit of adjusting that IC1-2 and IC1-3 constitute, and pass through comparator IC1-4 to switching tube V20, the coil of relay K A2 is arranged on switching tube V20 collector electrode, simultaneously, the normally-closed contact of relay K A2 is connected across between arbitrary phase line of electrical network and the ground wire.Wherein, comparator IC1-1, IC1-2, IC1-3 and V3, R3, V19, V16, C13, R4, R18, R19 form the short trouble identification circuit, its separately reverse input end form the end of adjusting by R3, V19, V16 and C13.R12 and IC1-3 output are formed AND circuit.Relay K A2 shown in the figure, triode V20 form performance element, and IC1-4 and peripheral cell are formed buffer stage, and it and guide loop R5, C18 are acceleration adhesives when starting for KA2, and KA2-1 is disconnected rapidly.

As shown in Figure 3, the top earth detector is the pseudo-central point testing circuit that is made of R35, R36, R37, V12, V13, V14 in the setting of tested electric network source side, and it detects output and exports the switch actuator part to via the circuit of adjusting that comparator IC2-1, IC2-2, IC2-3 and IC2-4 constitute.

In this top earth detector, rectifier diode V12, V13, V14, current-limiting resistance R35, R36, R37, filter capacitor C14, potentiometer RP form the detection of electrical leakage unit.Form the electric leakage identification circuit by V23, V26, IC2-1 and peripheral cell R23, R24, R25, R26, V26 is a voltage follower, and V23 is its family of power and influence, and R23, R24 are divider resistance, and IC2-1 is provided the current potential of adjusting.Comparator IC2-3 is an inverter, and R21, C15 and IC2-2 start delay circuit and prevent to send electricity moment misoperation.Comparator IC2-4 and peripheral cell R31, R32, C16, V5 are the fault memory circuit.

When electric power system did not have phase fault, voltage detection unit output was higher than the identification circuit terminal potential of adjusting, performance element KA1 adhesive, KA2-1 closure.

When electric power system generation phase fault, voltage detection unit is output as 0V, is lower than the IC1 inverting input, with door output electronegative potential, V20 ends, and KA2 discharges, the electric leakage unit leaks electricity, and is detected the V26 conducting by the top device, there is signal voltage at the R25 two ends, and IC2-1-goes out high potential, and are anti-phase through IC2-3, the output electronegative potential, memory circuit IC2-4 keeps electronegative potential, and KA2 discharges, disconnect main contactor line bag electric power loop, the switch disjunction.

Be provided with in the end voltage checkout gear respectively by pressurizer WY and Vc3, C7 rectifying and wave-filtering constitute for the circuit of adjusting provides two groups of power circuits of power supply signal, two groups of power supplys are respectively from the secondary winding of two voltage detecting transformer TV1, TV2.This circuit structure can guarantee that the working power of protective device is normal when arbitrary alternate being short-circuited.

In addition, also can adopt as shown in Figure 2 photoelectric coupled circuit as the voltage transformer of voltage detection device, cross-over connection is alternate in electric power system respectively through current-limiting resistance for its light-emitting diode, makes voltage swing become light intensity, according to the d. c. voltage signal that is subjected to output different value a little less than the light intensity.

Claims

1, a kind of Distant phase fault protector is characterized in that being provided with respectively end voltage checkout gear and top earth detector in tested electrical network; Described end voltage checkout gear is each alternate voltage detecting transformer TV1, TV2, TV3 or the optocoupler voltage sensor of being provided with respectively of load side at tested electrical network, the secondary end output of described transformer TV1, TV2, TV3 is connected to the circuit of adjusting of comparator IC1-1, IC1-2 and IC1-3 formation respectively, and pass through comparator IC1-4 to switching tube V20, the coil of relay K A2 is arranged on switching tube V20 collector electrode, simultaneously, the normally-closed contact of relay K A2 is connected across between arbitrary phase line of electrical network and the ground wire; Described top earth detector is the pseudo-central point testing circuit that is made of R35, R36, R37, V12, V13, V14 in the setting of tested electric network source side, and it detects output and exports the switch actuator part to via the circuit of adjusting that comparator IC2-1, IC2-2, IC2-3 and IC2-4 constitute.

2, Distant phase fault protector according to claim 1; it is characterized in that in described end voltage checkout gear, being provided with respectively by pressurizer WY and VC3, C7 rectifying and wave-filtering constitute for the circuit of adjusting provides two groups of power circuits of power supply signal, described two groups of power supplys are respectively from the secondary winding of two voltage detecting transformer TV1, TV2.