CN2245290Y

CN2245290Y - Selective comprehensive protector for electrical leakage, phase-sensitive short circuit

Info

Publication number: CN2245290Y
Application number: CN 95239886
Authority: CN
Inventors: 郑明�
Original assignee: Individual
Current assignee: Individual
Priority date: 1995-06-06
Filing date: 1995-06-06
Publication date: 1997-01-15
Anticipated expiration: 2005-06-06

Abstract

The utility model relates to a selective comprehensive protector for electrical leakage, phase-sensitive short circuit, which belongs to the coal mine electric field. Because a time delay circuit is added, the utility model overcomes the defect that the existing protector does mistaken movement because of the existence of moment electrical leakage when a plurality of motors are started. The 20 pin of a current mutual inductor is respectively connected with D17, D18, is connected to the 4, 5 pins of U3 to compare after integrated via R7, R4 and R8, R5 and is output from the 2 pin, and is connected to the 8 pin of U3 after charged and discharged via R11, C6. A power supply is connected to 7 pin of U3 after divided with voltage via R10, R12, and is output to a leakage selecting and amplifying circuit from the 1 pin of U3.

Description

Selective leakage, phase sensitivity short circuit comprehensive protection device

A kind of selective leakage, phase sensitivity short circuit comprehensive protection device are used for the protection of the DW80Z type feeding switch of the underground power supply used use in colliery, belong to mining appliance field.

At present, to be called phase sensitivity comprehensive protection device, the patent No. be that 932363571 utility model patent can not trip when having solved the generation short circuit that 350/220-660 type feeding switch that domestic mine power supply uses in use exists and produces naked light moment to name; Can not distinguish electric motor starting electric current and short circuit current; Minimum setting value is bigger than normal; Length, the less supply network of load bring the difficulty of adjusting to give power supply network; Problems such as electric leakage causes total system to have a power failure, transship and short phase time can not play a protective role.This technology is: any two-phase of the power transformer of protector and power generating facilities and power grids is connected, and it has two current transformers, and zero sequence current mutual inductor is enclosed within on the power generating facilities and power grids and with card and links to each other, and phase sequence transformer and electrical network and card join.Current transformer and power generating facilities and power grids, card join, and card and electronics master control borad join.Circuit on the electronics master control borad is: operating voltage is adjusted through bridge heap and integrated package from two secondary on the power transformer, be added to respectively on universal coil and three integrated packages, the beautiful bridge heap that is added to after the phase shifter phase shift of the electricity that three secondary of phase sequence transformer take out is gone up relatively; The voltage that current transformer takes out also is added to Qiao Duishang, voltage relatively is through integration circuit integration, through integrated package relatively, be passed to actuator's triode and universal coil, the zero sequence transformer takes out voltage and is added to three bridge heaps and three secondary of phase sequence transformer respectively, after the voltage phase shift of taking out and the voltage ratio of not phase shift, behind the integrating circuit integration, be added on the integrated package and compare again, be passed to integrated package at last and be added to actuator.

The deficiencies in the prior art part is: during the multiple motors starting, have the moment electric leakage, and protector is made misoperation to it.

The purpose of this utility model is: on the basis of original technology, increase the delay circuit of electric motor starting, make original phase sensitivity comprehensive protection device, the misoperation of protector when overcoming the multiple electric motors starting.

The technical solution of the utility model is: be made up of master control transformer (1), switch (2), general-purpose relay (3), Electronic Control plate (4), zero-sequence transformer (5), three former devices such as current transformer.Circuit on the Electronic Control plate is such: 10 pin of master control transformer are connected with any two-phase of power generating facilities and power grids respectively with 11 pin, and line voltage is become the 27V alternating current.Secondary 12 is connected with bridge heap D1-D4 with secondary 13, gets 21V-29V voltage after the rectification, after U1 (7824) voltage stabilizing, divides two-way, and one the road to relay ZJ, wait action; U2 (LM339) 11 pin are arrived as operation voltage in another road after the R4 dividing potential drop.Current transformer A20 pin and secondary 15,14 connect D5-D8 bridge heap, carrying out linking after the phase bit comparison of voltage and current 5 pin of U2 here compares with the voltage of 4 pin that are stored in U2, link 10 pin of U2 again so that make comparisons with the 11 pin voltages of U2, comparator produces upset and control triode T action.21 limits of current transformer B and secondary 16,17 connect D9-D12 bridge heap, and its effect purpose of 10 pin that meets behind 7 pin, 6 pin of U2 U2 is with last same.22 pin of current transformer and secondary 18,19 meet bridge heap D13-D16, after link 9 pin of U2, its effect, purpose are with 20 pin.Current transformer 20 pin are connected with D17, D18 respectively again, through the rectification of D17 after behind the R7, C4 integration to U3 (LM339) 5 pin, through the rectification of D18 after behind the R8, C5 integration to 4 pin of U3, when electric motor starting, R7, C4 are faster than R8, C5 integrating rate, so the 5 pin voltages of moment U3 are greater than the 4 pin voltages of U3.2 pin of U3 are output as supply voltage, and C6 is charged.After electric motor starting finished, the 20 pin output voltages of current transformer A were definite value, and R8 resistance value ratio R7 resistance is big, R8 voltage ratio R7 dividing potential drop height, so the 5 pin voltages of U3 are less than the 4 pin voltages of U3, overturn 2 pin of U3 of comparator are output as 0, and C6 discharges, when C6 has 7 pin voltages greater than U3, it is 0 that U3 exports 1 pin, and when C6 discharged to R11, discharge voltage was lower than the 7 pin voltages of U3,1 pin of output U3 is a supply voltage, and C6 is a delay time to R11 discharge time.

Of the present utility model being characterised in that: the connection of its delay circuit is: 20 pin and D17, the D18 of current transformer A join, through after the halfwave rectifier of D17, D18, connect 5 pin that are added to U3 behind the route R7, C4 integration of D17, connect 4 pin that are added to U3 behind the route R8, C5 integration of D18, the output of 2 pin of U3 is added to 6 pin of U3 behind R11, C6 integration; Zero-sequence transformer 23 pin connect U4 (LM339) 5 pin, the 1 pin output of U3 connects 4 pin of U4 after R14, R15 dividing potential drop, 2 pin output from U4, connect 7 pin of U4, output to from 1 pin of U 4 through the U4 waveform shaping and to select drain circuit, when zero-sequence transformer has signal, when promptly 5 pin of U4 had voltage greater than R14, R15 dividing potential drop, comparator overturn.

Fig. 1 is a former device connection layout of the present utility model.

Fig. 2 is the circuit diagram of the utility model electronics master board.

Below in conjunction with embodiment to the further enumeration in addition of the utility model.10 pin of master control transformer (1) are connected with any two-phase of power generating facilities and power grids respectively with 11 pin, line voltage is become the 27V alternating current, secondary 12 connects the D1 positive pole, secondary 13 connects the D2 positive pole, after bridge heap D1-D4 rectification, get direct current 21V-29V, after U1 (7824) voltage stabilizing, the one road links relay (3) ZJ, waits action.Another road after the R4 dividing potential drop as the operation voltage of 11 pin of U2.Current transformer (6) 20 pin and secondary 15,14 connect D5-D8 bridge heap, carrying out linking after the phase bit comparison of voltage and current 5 pin of U2 here compares with the voltage that is stored in 4 pin, link the voltage of 11 pin of 10 pin of U2 and U2 again and make comparisons, produce upset back control triode T (3CG5E).21 limits of current transformer (7) and secondary 16,17 connect 6,7 pin that meet U2 after the D9-D12 bridge is piled, and are added to 10 pin of U2 again, its effect and purpose and last identical.Current transformer (8) 22 pin and secondary 18,19 connect 9 pin of linking U2 behind the bridge heap D13-D16, are added to 10 pin of U2 after the 13 pin output of U2.Delay circuit is made up of current transformer (6) 20 pin, D17, D18, U3, R7, R8, C5, C4, C6, R11 etc.20 pin tap D17, D18 connect the rectification of D17 after be added to 5 pin of U3 behind the R7, C4 integration; Connect the rectification of D18 after be added to 4 pin of U3 behind the R8, C5 integration.When first electric motor starting, R7, C4 are faster than R8, C5 integrating rate, thus the 5 pin voltages of instantaneous U3 greater than the 4 pin voltages of U3,2 pin of U3 are output as supply voltage, promptly C6 are charged.After electric motor starting finished, 20 pin output voltages of current transformer (6) were definite value, because R8 resistance value ratio R7 resistance is big, so R8 voltage ratio R7 dividing potential drop height, promptly the 5 pin voltages of U3 are greater than the 4 pin voltages of U3, and this moment, 2 pin of U3 were output as 0, and C6 discharges.The 6 pin voltages of U3 are greater than the 7 pin voltages of U3 when C6 has voltage, and 1 pin of U3 is output as 0.When C6 discharged to R11, when its voltage was lower than the 7 pin voltages of U3, it was supply voltage that U3 exports 1 pin.So C6 is a delay time to R11 discharge time.When 1 pin of U3 was output as 0, it is added on the U4 integrated package was 0 through the R17 bias voltage, even leaky is arranged, just the output voltage of zero-sequence transformer (5) 23 pin can not be exported at 2 pin of U4, selects drain circuit inoperative to the rear portion.When 1 pin of U3 is output as supply voltage, integrated package U4 has operating voltage, when electric leakage takes place, 4 pin of the output voltage of zero-sequence transformer (5) 23 and 5 pin of U4 and U4 relatively, the 2 pin output voltages of U4 are supply voltage, 7 pin of receiving U4 carry out waveform shaping, are input to the rear portion and select the drain circuit operate as normal.After first electric motor starting finishes; the delay circuit end-of-job; 20 pin voltages of current transformer (6) are definite value; 4 pin of U35 pin, U3 carry out the overlapping portion voltage integrating meter again during second electric motor starting on former basic voltage; the speed of its integrating rate plays the delay protection effect equally, operation principle with first with, in the 3rd when starting, is too; when some electric motor startings have electric leakage, can both play the delay protection effect.

The utility model and having compared in technology has and can solve multiple electric motors and start The time have moment electric leakage, protector does not produce the function of misoperation to it.

Claims

1, a kind of selective leakage, phase sensitivity short circuit comprehensive protection device, form by master control transformer, electronic card, zero-sequence transformer, current transformer, it is characterized in that: master control transformer one end and power generating facilities and power grids link, one end and card link, current transformer and power generating facilities and power grids link, one end and card link, zero-sequence transformer and power generating facilities and power grids link, one end and card link, the delay circuit of electronics master control borad is: current transformer 20 pin tap D17, D18, connect D17 a road through the D17 halfwave rectifier, behind R7, the C4 integration to the U35 pin; Connect D18 a road through the D18 halfwave rectifier, to 4 pin of U3, by the 2 pin output of U3, connect 6 pin of U3 behind R8, the C5 integration through R11, C6 through back relatively, power supply connect 7 pin that meet U3 after R10, the R12 dividing potential drop from 1 pin of U3 to choosing leakage amplifying circuit; Amplifying circuit is leaked in choosing: zero-sequence transformer 23 pin connect 5 pin of U4, and the 1 pin output of U3 connects 4 pin of U4 after R14, R15 dividing potential drop, from the 2 pin output of U4, connect 7 pin of U4 after the comparator upset, export 6 pin that 1 pin feeds back to U4.