CN104377650A - YNd7 wiring transformer longitudinal differential protection current phase compensation method - Google Patents

Abstract

The invention belongs to a relay protection control technology of a power transmission and distribution network, and particularly relates to an YNd7 wiring transformer longitudinal differential protection current phase compensation method. According to the method, the d-side b-phase TA secondary winding current of an YNd7 wiring transformer is connected to an a-phase current loop on the d side of differential protection of an YNd1 wiring microcomputer transformer; the d-side a-phase TA secondary winding current of the YNd7 wiring transformer is connected to a b-phase current loop on the d side of differential protection of the YNd1 wiring microcomputer transformer; the d-side c-phase TA secondary winding current of the YNd7 wiring transformer is connected to a c-phase current loop on the d side of differential protection of the YNd1 wiring microcomputer transformer; by the adoption of software phase compensation of an YNd1 wiring microcomputer transformer differential protection device, current phase compensation is conducted on YNd7 wiring transformer differential protection. The YNd7 wiring transformer longitudinal differential protection current phase compensation method is simple in principle and convenient to implement and can complete current phase compensation of the YNd7 wiring transformer differential protection.

Description

The compensation method of YNd7 wiring transformer longitudinal differential protection current phase

Technical field

The invention belongs to the relay protection and control technology of electrical power distribution electric network, relate to a kind of method that YNd7 wiring transformer longitudinal differential protection current phase compensates.

Background technology

Because transformer each side electric current possibility phase place is inconsistent, therefore transformer longitudinal linked differential protection (hereinafter referred to as transformer differential protection) will carry out current phase compensation.The method that transformer differential protection current phase compensates has two kinds: 1, traditional analog shifter: such as YNd11 transformer Y side current transformer (hereinafter referred to as TA) secondary winding adopts triangle d-11 wiring, d side TA secondary winding adopts star Y-12 wiring; 2, digit shifter: namely utilize software program and computing formula to carry out electric current phase shift to complete phase compensation.At present; 220kV and above tranformer protection are generally main protection backup protection integrated design, duplicate system retrofit; main protection backup protection integrated design is main protection and all backup protections all use same hardware and software in a cabinet, and the electric current of the every side of transformer main protection backup protection, voltage are all adopt TA, voltage transformer same group of secondary winding.Because main protection backup protection integrated transformer protective current loop is the same current circuit adopted; therefore traditional analog shifter can not be adopted to carry out current phase compensation; therefore the TA of each side of transformer must adopt wye connection, adopts electric current digit shifter to carry out phase compensation.110kV and following microcomputer transformer differential protection do not adopt traditional analog shifter to carry out current phase compensation at present yet; the TA of each side generally also adopts wye connection; also the electric current software phase compensation of differential protection is adopted, and progressively to main protection backup protection integrated design, two coverization configuration transition.Such as, but current each tranformer protection manufacturer differential protection electric current software phase compensating method only develops several conventional transformer connection group usually, and YNd1 wiring group and wiring combination etc. thereof, can not adapt to other wiring groups and wiring compound mode.

Summary of the invention

Problem to be solved by this invention is; there is provided one can utilize YNd1 transformer differential protection electric current software Phase Compensation System; complete the current phase compensation that various electric pressure transformer is YNd7 wiring (containing Yd7 wiring) transformer differential protection, and the method that principle YNd7 transformer longitudinal linked differential protection current phase that is simple, that implement conveniently, meet transformer differential protection current phase compensation principle compensates.

YNd7 transformer differential protection current phase of the present invention compensation method is:

YNd7 high voltage side of transformer, low-pressure side TA secondary winding all connect as wye connection, and this YNd7 transformer Y side TA secondary winding A phase current, B phase current, C phase current access the A phase current of YNd1 transformer differential protection, B phase current, C phase current loop respectively; The concrete grammar of YNd7 transformer d side TA secondary winding each phase current access YNd1 wiring microcomputer transformer differential protection is as follows:

(1) by a phase current loop of YNd7 wiring transformer d side b phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side;

(2) by the b phase current loop of YNd7 wiring transformer d side a phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side;

(3) by the c phase current loop of YNd7 wiring transformer d side c phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side;

(4) utilize the software phase compensation of YNd1 wiring microcomputer transformer differential protection, phase compensation is carried out to YNd7 wiring transformer differential protection.

The transformer longitudinal linked differential protection general principle that the method for the phase compensation of YNd7 wiring transformer longitudinal differential protection electric current of the present invention meets completely, compared with the method used in existing based Transformer differential protection, tool has the following advantages:

1, the current phase compensation technique scheme of transmission and distribution networks electric substation YNd7 wiring various electric pressure transformer longitudinal linked differential protection device is applicable to.

2, by the conversion of each phase current of access transformer longitudinal linked differential protection device, YNd7 wiring transformer differential protection is converted to YNd1 wiring transformer differential protection, recycle the current phase compensation scheme of existing YNd1 microcomputer transformer differential protection, achieve the current phase compensation scheme of all YNd7 wiring transformer longitudinal differential protection devices, simple and practical, secondary circuit is changed little, easily realizes;

3, the current phase compensation scheme of YNd7 wiring transformer longitudinal differential protection device does not need the current phase compensation scheme changing existing YNd1 microcomputer transformer longitudinal differential protection device inside.

Accompanying drawing explanation

Fig. 1 is YNd7 transformer connection figure corresponding to the inventive method;

Fig. 2 is YNd1 transformer corresponding to the inventive method and YNd7 transformer connection graph of a relation.

Fig. 3 is the YNd7 transformer differential protection current phase compensation principle figure of the inventive method.

Specific embodiments

1, the phase relation of YNd7 wiring transformer and YNd1 series wiring transformer

Fig. 1 is shown in by YNd7 wiring transformer winding diagram.Because YNd7 high voltage side of transformer, low-pressure side three-phase voltage are all symmetrical, as long as therefore take out 1 line voltage compare, so have in advance 210 degree.YNd1 wiring transformer winding diagram is shown in Fig. 2 a), in like manner YNd1 transformer in advance 30 degree.We are YNd7 transformer with YNd11 transformer think and compare YNd1 transformer and YNd7 step down side by homophase between relation.And YNd7 step down side for low pressure a winding in A phase iron core column voltage- fig. 2 a) in we also can find the voltage of low pressure a winding in A phase iron core column- (regard as and be equivalent to YNd7 step down side ), the lead-out wire pile crown of Fig. 2 a) tail " x " of mesolow a winding is labeled as " a ", the lead-out wire pile crown of head " a " is labeled as " b ", remaining another lead-out wire pile crown note is " c ", so obtain Fig. 2 b); Analysis chart 2b) obtain another kind of YNd7 wiring transformer winding diagram.Namely the d side phase relation of YNd1 wiring transformer and YNd7 wiring transformer is as table 1.

The d side phase relation contrast table of table 1, YNd7 wiring transformer and YNd1 wiring transformer

2, YNd7 transformer current phase compensating method

YNd1 wiring transformer differential protection, manufactory has achieved transformer differential protection electric current software compensation in protection equipment for transformer.Requirement YNd7 high voltage side of transformer, low-pressure side TA secondary winding all connect as wye connection.

YNd1 wiring transformer d side winding and YNd7 wiring transformer d side winding each phase current relation in comparison sheet 1 (think each phase current homophase of YNd1 and YNd7 wiring transformer Y side winding); be not difficult to find b phase current, a phase current, the c phase current same-phase of a phase current of YNd1 wiring transformer d side winding, b phase current, c phase current and YNd7 wiring transformer d side winding; therefore, the compensation method of YNd7 wiring transformer differential protection current phase is drawn:

(1) each phase current of this YNd7 transformer Y side TA secondary winding each phase current access YNd1 wiring transformer differential protection is constant, and namely YNd7 wiring transformer Y side TA secondary winding A phase current, B phase current, C phase current connect A phase current, B phase current, the C phase current of YNd1 transformer differential protection respectively.

(2) accessing each phase current of YNd1 wiring transformer this YNd7 transformer d side TA secondary winding of differential protection is: by the b phase current loop of a phase current loop of the b phase TA secondary winding electric current of YNd7 wiring transformer d side access YNd1 wiring microcomputer transformer differential protection d side, a phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side, the c phase current loop of c phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side.

(3) by this conversion, YNd7 wiring transformer differential protection just changes YNd1 wiring transformer differential protection into; The electric current software phase compensation of recycling YNd1 wiring microcomputer transformer differential protection, thus the current phase finally achieving YNd7 wiring transformer differential protection compensates.Fig. 3 is shown in concrete wiring.

Claims (1)

1. a YNd7 transformer differential protection current phase compensation method, is characterized in that:

YNd7 high voltage side of transformer, low-pressure side TA secondary winding all connect as wye connection, and this YNd7 transformer Y side TA secondary winding A phase current, B phase current, C phase current access the A phase current of YNd1 transformer differential protection, B phase current, C phase current loop respectively; The concrete grammar of YNd7 transformer d side TA secondary winding each phase current access YNd1 wiring microcomputer transformer differential protection is as follows:

(1) by a phase current loop of YNd7 wiring transformer d side b phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side;

(2) by the b phase current loop of YNd7 wiring transformer d side a phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side;

(3) by the c phase current loop of YNd7 wiring transformer d side c phase TA secondary winding electric current access YNd1 wiring microcomputer transformer differential protection d side;

(4) utilize the software phase compensation of YNd1 wiring microcomputer transformer differential protection, phase compensation is carried out to YNd7 wiring transformer differential protection.