CN1896757A

CN1896757A - Phase-shifting fail ture by couting discrimination

Info

Publication number: CN1896757A
Application number: CN 200610085612
Authority: CN
Inventors: 李海英; 王俊生; 卢宇
Original assignee: NR Electric Co Ltd
Current assignee: NR Electric Co Ltd
Priority date: 2006-06-28
Filing date: 2006-06-28
Publication date: 2007-01-17
Anticipated expiration: 2026-06-28
Also published as: CN100529781C

Abstract

The measured method to judge the phase conversion failure, it is composed of the 2 following parts: phase conversion failure judgment component and measured component, the measured method is divided into single bridge and couple bridge and any bridge measured; The single bridge is divided into Y bridge measured and D bridge measured; a phase conversion failure matched the condition records Y bridge measured pulse; or a phase conversion failure matched the condition records D bridge measured pulse; each phase conversion failure matched the condition records a couple bridge measured pulse; Y bridge or D bridge or couple bridge measured pulse is switched in the measured pulse input end of the measured component respectively; phase conversion is in the setting time width , the measured number reaches the setting measured fixed value , doing the protect action based on phase conversion failure principle.

Description

Method with metering identification commutation failure

One, technical field

The present invention relates to D.C. high voltage transmission and judge the new method of the commutation failure of converter valve group, and protective relaying device.

Two, background technology

D.C. high voltage transmission is because its distinctive advantage, such as: long distance, high-power, asynchronous networking, power quick adjustment, trend controllability, the economy of transmitting electricity etc. are applied more and more widely.The core of HVDC (High Voltage Direct Current) transmission system is a high-voltage dc transmission electric control protection system, and it comprises control system and protection system.The HVDC (High Voltage Direct Current) transmission system most important equipment is the converter valve group.

The commutation failure of converter valve group is D.C. high voltage transmission common faults and phenomenon.Problems such as AC system disturbance or trigger pulse loop all can produce the commutation failure of converter valve group.System produces continuous converter valve group commutation failure and just is considered to fault, and individual other converter valve group commutation failure does not have big harm to system.

The method of the commutation failure of existing judgement converter valve group, employing be the time-delay principle.

The method of the commutation failure of existing judgement converter valve group can be described below:

The implication of the symbol that is adopted during description is seen Fig. 1:

Among Fig. 1, IVY refers to that valve side Y connects the electric current of winding, and IVD refers to that valve side Δ connects the electric current of winding; IDP refers to utmost point bus valve side DC current, and IDNC refers to neutral line valve side DC current.

IVY, IVD are alternating quantity in real system, need its equivalence is DC current in calculating, and equivalent method is as follows:

| IVY|=max (abs (IVY_L1), abs (IVY_L2), abs (IVY_L1)), perhaps

|IVY|＝0.5*(abs(IVY_L1)+abs(IVY_L2)+abs(IVY_L1))

| IVD|=max (abs (IVD_L1 IVD_L2), abs (IVD_L2 IVD_L3), abs (IVD_L3IVD_L1)), perhaps

|IVD|＝0.5*(abs(IVD_L1?IVD_L2)+abs(IVD_L2?IVD_L3)+abs(IVD_L3IVD_L1))

In the formula, Lx---x=1,2,3, refer to a, b, c phase.

The method of the commutation failure of existing judgement converter valve group has:

IDP-|IVY|＞definite value 1 and | IVY|＜definite value 2*IDP (1)

IDP-|IVD|＞definite value 1 and | IVD|＜definite value 2*IDP (2)

Satisfy condition after (1) or (2), satisfy certain time-delay, the protection action.

The weak point of the method for the commutation failure of existing judgement converter valve group: the commutation failure number of times that can not reflect converter valve group in a period of time strictly according to the facts.And what of commutation failure number of times in a period of time are to weigh the important indicator that the converter valve group can bear ability, also are the important symbols of the reflection system failure order of severity.

Three, summary of the invention

The objective of the invention is: a kind of metering principle of novel judgement converter valve group commutation failure is provided, can reflects the number of times of commutation failure, and by the definite value action of adjusting.

The metering method of novel judgement converter valve group commutation failure is made of jointly following 2 parts:

1, phase conversion failure judgment component

| IVY|=max (abs (IVY_L1), abs (IVY_L2), abs (IVY_L1)), perhaps

|IVY|＝0.5*(abs(IVY_L1)+abs(IVY_L2)+abs(IVY_L1))

|IVD|＝0.5*(abs(IVD_L1?IVD_L2)+abs(IVD_L2?IVD_L3)+abs(IVD_L3IVD_L1))

In the formula, IVY refers to that valve side Y connects the electric current of winding, and IVD refers to that valve side Δ connects the electric current of winding; Lx---x=1,2,3, refer to a, b, c phase.

IDP-|IVY|＞definite value 1 and | IVY|＜definite value 2*IDP

(3)

IDP-|IVD|＞definite value 1 and | IVD|＜definite value 2*IDP

(4)

In the formula, IDP refers to utmost point bus valve side DC current.IDP also can replace with IDNC, and IDNC refers to neutral line valve side DC current.

Service condition (3) or (4), about 5 milliseconds of monostable outputs.Produce as a commutation failure, i.e. a metering pulse.

Annotate: the implication of monostable output is, is input as very, and output be very in the given time, is output as vacation thereafter; No matter be input as the length of true duration.

Metering element: input end----time width, metering pulse, metering definite value, Enable Pin; Output terminal----action outlet; Parameter: maximum metering number.

Function is: 1, each metering pulse arrives, and the metering counter adds 1; In the time width window, the metering counter reaches the metering definite value, and Enable Pin is true, and then the action outlet is for true.The time width window is a dynamic continuous mobile window.2, if Enable Pin is false, the outlet of then whenever moving is vacation.3, metering definite value is the setting value of an input; When the metering definite value of setting during greater than parameter value (maximum metering number), actual metering definite value is parameter value (a maximum metering number); That is to say that actual metering definite value is parameter value and the minimum value of setting definite value (metering).Fig. 2 is a metering element synoptic diagram, and parameter is 60 metering element synoptic diagram.

2, metering principle

Divide single bridge and doube bridge (bridge arbitrarily) metering.Single bridge metering divides metering of Y bridge and the metering of D bridge again.

The satisfy condition commutation failure of (3) is counted Y bridge metering pulse; The satisfy condition commutation failure of (4) is counted D bridge metering pulse; The satisfy condition commutation failure of (3) or (4) is all counted the doube bridge metering pulse one time.Y bridge or D bridge or doube bridge metering pulse, the metering pulse input end of access metering element separately.

Commutation failure is in the time width of setting, and number of times arrives the metering definite value, then commutation failure metering principle protection action.

Fig. 3 commutation failure Y bridge metering principle realizes block diagram, shows that typical commutation failure Y bridge metering principle realizes block diagram.The metering principle roughly the same for other bridge (D bridge or doube bridge).

Characteristics of the present invention:

The present invention introduces the metering element, and dynamic continuous mobile window obtains the number of times of commutation failure in the time window reliably.

Four, description of drawings

Fig. 1 by the present invention calculate the implication explanation of use value

Fig. 2 is a metering element synoptic diagram of the present invention

Fig. 3 realizes block diagram for commutation failure Y bridge metering principle of the present invention

Five, embodiment

Read sampled value, will exchange and survey the electric current conversion is DC current.Calculate (3), (4) formula, obtain metering pulse.

Utilize the realization block diagram of similar Fig. 3, realize the commutation failure metering principle protection of single bridge and doube bridge.Specific as follows:

Y bridge commutation failure metering principle, the realization block diagram of employing Fig. 3.D bridge commutation failure metering principle, ' (3) satisfy condition ' changes ' (4) satisfy condition ' in the realization block diagram with Fig. 3.Doube bridge commutation failure metering principle, ' (3) satisfy condition ' changes ' (3) or the condition of satisfying condition (4) ' in the realization block diagram with Fig. 3.

Enable Pin can be thrown easily and be moved back this principle protection.Help application such as debugging.

The time width window is a dynamic continuous mobile window.

Definite value is selected reference: definite value 1 about 0.133 ± 0.02 times of dc rated current, definite value 2 about 0.65 ± 0.1; Metering time fixed value list bridge has two kinds of 200ms and 600ms, and doube bridge has two kinds of 2s and 10s, and corresponding number of times fixed value list bridge has two kinds of 9 times and 26 times, and doube bridge has two kinds of 105 times and 450 times.

Above-mentioned condition and not exclusive qualification.

Claims

1, with the method for metering identification commutation failure, it is characterized in that constituting by following 2 parts:

(1) phase conversion failure judgment component

| IVY|=max (abs (IVY_L1), abs (IVY_L2), abs (IVY_L1)), perhaps

|IVY|＝0.5*(abs(IVY_L1)+abs(IVY_L2)+abs(IVY_L1))

|IVD|＝0.5*(abs(IVD_L1?IVD_L2)+abs(IVD_L2?IVD_L3)+abs(IVD_L3IVD_L1))

IDP-|IVY|＞definite value 1 and | IVY|＜definite value 2*IDP

(3)

IDP-|IVD|＞definite value 1 and | IVD|＜definite value 2*IDP

(4)

In the formula, IDP refers to utmost point bus valve side DC current.IDP also can replace with IDNC, and IDNC refers to neutral line valve side DC current;

Service condition (3) or (4), 5 milliseconds of monostable outputs; Produce as a commutation failure, i.e. a metering pulse;

(2) metering element: input end----time width, metering pulse, metering definite value, Enable Pin; Output terminal----action outlet; Parameter: maximum metering number;

Each metering pulse arrives, and the metering counter adds 1; In the time width window, the metering counter reaches the metering definite value, and Enable Pin is true, and then the action outlet is for true; The time width window is a dynamic continuous mobile window; If Enable Pin is false, the outlet of then whenever moving is vacation; The metering definite value is the setting value of an input; When the metering definite value of setting during greater than parameter value, actual metering definite value is a parameter value;

The metering method is divided single bridge and doube bridge or bridge metering arbitrarily; Single bridge metering divides metering of Y bridge and the metering of D bridge again;

The satisfy condition commutation failure of (3) is counted Y bridge metering pulse; Or a commutation failure of satisfy condition (4), count D bridge metering pulse; The satisfy condition commutation failure of (3) or (4) is all counted the doube bridge metering pulse one time; Y bridge or D bridge or doube bridge metering pulse, the metering pulse input end of access metering element separately; Commutation failure is in the time width of setting, and number of times arrives the metering definite value, then commutation failure metering principle protection action.

2, by the described method of claim 1, it is characterized in that definite value 1 about 0.133 ± 0.02 times of dc rated current, definite value 2 about 0.65 ± 0.1 with metering identification commutation failure.