CN2482255Y

CN2482255Y - Phase-demodulating amplitude discrimination earth leakage protector

Info

Publication number: CN2482255Y
Application number: CN 01236678
Authority: CN
Inventors: 吴希宽
Original assignee: ZIBO ELECTRICAL APPLIANCE FACTORY
Current assignee: ZIBO ELECTRICAL APPLIANCE FACTORY
Priority date: 2001-04-26
Filing date: 2001-04-26
Publication date: 2002-03-13
Anticipated expiration: 2011-04-26

Abstract

The utility model belongs to the field of an emergency protection circuit device responding to an earthed failure current. The utility model is characterized in that a delay and protection circuit is arranged between the I/O interface of a single-chip microcomputer circuit and the input terminal of an executive circuit. The service life of the leakage current protector and the power supply device can be prolonged by utilizing the utility model, and the damage and the influence of the leakage current protector, the power supply device and the electric network caused by the continuous startup of an inductive load can be avoided. The setting time of the delay actuation can be adjusted by adjusting the parameter of the electric capacity and the resistor of the delay and protection circuit according to the condition of different load, the parameter setting value of the program running in the microcomputer is not needed to adjust, and the product has strong adaptability and good versatility.

Description

The phase-detecting amplitude-detecting leak protector

The utility model belongs to the emergency protective circuit device field that the fault current to ground connection reacts, and relates to a kind of earth leakage protective device that is applicable to industry for, power consumption equipment.

In the prior art, the phase-detecting amplitude-detecting leak protector disconnects the power supply of the closing contactor coil of confession, power consumption equipment by its executive circuit when detecting the alternating current circuit Ground leakage current greater than set point.For the earth fault of some short time, earth leakage protective device returns to set point when following detecting the alternating current circuit Ground leakage current, and the closing contactor that allows power supply unit is reclosing once more.But; for some the instantaneity earth fault that takes place repeatedly; the closing contactor of power supply unit is reclosing continually; output element and closing contactor to the earth leakage protective device executive circuit damage; can cause burning of closing contactor contact and power supply unit major loop contact terminal when serious, greatly shorten the useful life of equipment.

The purpose of this utility model provides a kind of delay protection circuit that has, and can prolong the useful life of earth leakage protective device and power supply unit preferably, and delay protection can be adjusted operate time, the phase-detecting amplitude-detecting leak protector that the adaptation of product is strong.

In order to achieve the above object; the utility model provides a kind of phase-detecting amplitude-detecting leak protector; comprise testing circuit; amplifying circuit; phase detecting circuit; amplitude detection circuit; the phase reference circuit; single chip circuit; executive circuit and power supply; testing circuit is connected with amplitude detection circuit with phase detecting circuit through amplifying circuit; the input termination power of phase reference circuit; single chip circuit I/O interface respectively with phase detecting circuit; the output of amplitude detection circuit and phase reference circuit and the input of executive circuit connect, and it is characterized in that: between single chip circuit I/O interface and executive circuit input the delay protection circuit is set.

Described delay protection circuit is made of electric capacity and resistance; described capacitance series is between single chip circuit I/O interface and executive circuit input; one end of corresponding I/O interface with single chip circuit of one end of described resistance and electric capacity is connected the other end ground connection of resistance.

Compared with prior art, the utlity model has following characteristics:

1. set up the delay protection circuit, reduced the closing contactor of power supply unit and the action frequency of power supply unit major loop contact terminal, can prolong the useful life of earth leakage protective device and power supply unit preferably.

2. avoided continuous infringement and the influence that starts earth leakage protective device and power supply unit and electrical network brought of inductive load.

3. can adjust the setting time of deferred action by the parameter of adjusting electric capacity, resistance in the delay protection circuit according to the unequally loaded situation, not need the pre-set parameter of working procedure in the single-chip microcomputer is adjusted, the adaptation of product is strong, and versatility is good.

Below in conjunction with drawings and Examples the utility model is further elaborated:

Fig. 1 is an electrical structure block diagram of the present utility model.

Fig. 2 is an embodiment line map of the present utility model.

Among Fig. 1, the utility model comprises testing circuit 1, amplifying circuit 2, phase detecting circuit 3, amplitude detection circuit 4, phase reference circuit 5, single chip circuit 6, delay protection circuit 7, executive circuit 8 and power supply 9.Testing circuit is connected with amplitude detection circuit with phase detecting circuit through amplifying circuit; single chip circuit I/O interface is connected with the output of phase detecting circuit, amplitude detection circuit and phase reference circuit and the input of delay protection circuit respectively, and the delay protection circuit is arranged between single chip circuit I/O interface end and the executive circuit input.

Among Fig. 2, the utility model comprises the testing circuit that is made of zero-sequence transformer T Δ; by diode D1; D2; D3; D4; resistance R 1; R2; R3; the amplifying circuit that R4 and integrated circuit (IC) 1 constitute; by resistance R 8; R9; R10; the phase detecting circuit that R18 and integrated circuit (IC) 2 constitute; by resistance R 5; R6; R7; the amplitude detection circuit that capacitor C 2 and C3 constitute; by resistance R 11; R12; R13; the phase reference circuit that R14 and integrated circuit (IC) 3 constitute; by integrated circuit (IC) 4; crystal oscillator XT and capacitor C 11; the single chip circuit that C12 constitutes; the delay protection circuit that constitutes by capacitor C 4 and resistance R 17; by triode BG1; the executive circuit that diode D8 and relay J 1 constitutes and by transformer T1; rectifier bridge D; resistance R 18; capacitor C 5; C6; C7; C8; C9; C10; C11; voltage stabilizing didoe D10; the power circuit that D11 and D12 constitute.

Concise and to the point course of action of the present utility model:

By zero-sequence transformer T _ΔWith detected signal after amplifying circuit amplifies; one the tunnel delivers to the I/O interface RB4 of single chip circuit after phase detecting circuit is handled; the I/O interface RA1 of single chip circuit is delivered on another road after amplitude detection circuit is handled; single chip circuit is analyzed the signal of sending into; when reaching specified pulse action current value or gradual residue operating current value; make the closing contactor disjunction of power supply unit by executive circuit, realize the protection tripping operation.Simultaneously, single chip circuit to the signal of sending into compare, computing, calculate the situation of change of every phase residual current, make equipment realize breaker tripping and closing by executive circuit.

When the utility model is switched on work at the beginning, the RB6 end output high level of integrated circuit (IC) 4, because capacitor C 4 both end voltage can not be suddenlyd change, therefore, the b of triode BG1 is high potential very, the BG1 conducting, and relay J 1 gets electric adhesive, the closing contactor of its normally opened contact control power supply unit or the operation contactor of power consumption equipment get electric adhesive, thus finish give, function of supplying power.Simultaneously, the RB6 of IC4 end charges through 15 couples of C4 of resistance R.Because resistance R 17 resistances are bigger; the C4 velocity of discharge is slow; when closing, earth leakage protective device has no progeny when sending reclosing command again at once; owing to have certain voltage on the C4; make the RB6 of integrated circuit (IC) 4 hold the high level of output to be not enough to reach the voltage that makes triode BG1 conducting at once, so not adhesive immediately of J1.After having only " time-delay " discharge, restart through capacitor C 4 and resistance R 17, J1 adhesive again, thus protected above-mentioned electric component and equipment can not damage because of starting continuously.

Load at different capabilities; can adjust the setting time of deferred action by the parameter of adjusting electric capacity, resistance in the delay protection circuit; do not need the pre-set parameter of working procedure in the single-chip microcomputer is changed; thereby simplified the adjustment work of adjusting of parameter; make that adaptability of the present utility model is strong, have good versatility.

The utility model embodiment typical element parameter:

Diode D1, D2, D3, D4, D8, rectifier bridge D:1N4000 series; Diode D10-D12:2CW series; Triode BG1:901 series; Capacitor C 2-C4:1-100 μ f; C5, C7, C9:100-470 μ f; C6, C8, C10:104; C11, C12:30pf; Resistance R 4:100-470k; R6:47-100 Ω; All the other resistance are 1-100k; Integrated circuit (IC) 1-IC3:LM series; IC4:PIC16 series; Relay J 1:12-24V DC; Transformer T:220/30V.

The utility model is applicable to that industry carries out supporting use for the earth leakage protective of, power consumption equipment with for the centralized control power consumption equipment.

Claims

1. phase-detecting amplitude-detecting leak protector; comprise testing circuit; amplifying circuit; phase detecting circuit; amplitude detection circuit; the phase reference circuit; single chip circuit; executive circuit and power supply; testing circuit is connected with amplitude detection circuit with phase detecting circuit through amplifying circuit; the input termination power of phase reference circuit; single chip circuit I/O interface respectively with phase detecting circuit; the output of amplitude detection circuit and phase reference circuit and the input of executive circuit connect, and it is characterized in that: between single chip circuit I/O interface and executive circuit input the delay protection circuit is set.

2. according to the described phase-detecting amplitude-detecting leak protector of claim 1; it is characterized in that described delay protection circuit is made of electric capacity and resistance; described capacitance series is between single chip circuit I/O interface and executive circuit input; one end of corresponding I/O interface with single chip circuit of one end of described resistance and electric capacity is connected the other end ground connection of resistance.