CN101330214B - TCR type SVC voltage control method for transformer substation - Google Patents

Abstract

The invention discloses a TCR type SVC voltage control method used in a transformer substation. The method comprises the following steps: the control objective fixed value as well as the adjusting dead area of 220/500 kV voltage and the limit value as well as the TCR power output upper and lower limit values of 10/35 kV voltage are set respectively; the 220/500 kV voltage and the 10/35 kV voltage are measured and judged; aiming at the different 220/500 kV and 10/35 kV voltages, different TCRs as well as the adjusting order and the adjusting method of a capacitive compensating branch are adopted. The method can effectively integrates the level of the 10/35 kV voltage while controlling the 220/500 kV voltage of the transformer substation, thereby avoiding the frequent switch of the capacitive compensating branch, considering the demands of various complicated working conditions, and having wider applicability; at the same time, a self-regulating factor fuzzy controller is adopted to control the TCR output, and an error weighting coefficient which automatically adjusts according to the error magnitude is introduced to satisfy the demands of different control stages, thereby improving the whole control effect.

Description

The TCR type SVC voltage control method that is used for transformer station

Technical field

The present invention relates to a kind of TCR type SVC voltage control method that is used for transformer station, particularly a kind of is that controlled target is taken into account the TCR type SVC voltage control method that 10/35kV voltage is adjusted with the 220/500kV of transformer station voltage.

Background technology

Reactive power all is crucial for the operation of electric power system and load.Along with power system development, the demand of reactive power being carried out quick dynamic compensation is increasing.Traditional reactive power dynamic compensation device is a synchronous compensator, but its loss and noise are bigger, the operation maintenance complexity, and response speed is slow, is replaced by silent oscillation reactive power compensator (SVC) gradually in recent years.Early stage SVC mainly is saturable reactor (SR) type, but because its iron core need be magnetized into saturation condition, loss and noise are bigger equally, and have some specific questions of nonlinear circuit, thereby fail to occupy the main flow of SVC device.This speech of SVC often specially refers to use the static passive compensation device of thyristor at present, wherein TCR (thyristor-controlled reactor) is topmost application form, finishes the function that idle dynamic is regulated but it often is used with the capacitive compensation branch road (FC) of switching.

From the pertinent literature analysis, study and use many SVC control methods at present and mainly comprise vector control, fuzzy control, nonlinear Control, fuzzy, self-adaptive PID, Fuzzy Variable-Structure Control or the like, they are each tool advantage on control performance, but controlled target is single relatively, mostly only with power factor or the voltage of certain grade as target, fail the complexity of the system that takes into full account, very not clear and definite for the switching of FC simultaneously with the coordination that TCR compensates yet.When TCR type SVC is used for the voltage control of transformer station, SVC is often via the low-voltage bus bar connecting system of transformer, and this section bus might not be pure compensation bus, sometimes also can insert the load of other normal operations, therefore under different system operational mode and various load level, its high and low side voltage levvl might not be very synchronous, low slightly and low-pressure side is higher or the high-pressure side is normal and low-pressure side is on the low side etc. the various complex situations in high-pressure side might appear, this moment, it probably caused the serious higher or on the low side of this section low-pressure side bus voltage when SVC only is controlled target with the high side voltage, not only influence this section bus user's the electricity quality of using, and can make FC branch road frequent movement, the useful life of very big reduction equipment, even cause system's concussion.Therefore, from point of view of practicability, voltage control to the TCR type SVC that is used for transformer station, must be based on TCR self quick adjustment, take all factors into consideration corresponding high pressure of system and low-pressure side voltage condition, guaranteeing to carry out on high-tension side voltage control under the precondition that low-pressure side voltage meets the demands, the extreme case when simultaneously must taking into account system breaking down.

Summary of the invention

The objective of the invention is to:, the invention provides a kind of TCR type SVC voltage control method that is used for transformer station for solving the SVC voltage control problem of no separate compensation bus.

The present invention program is as follows: calculate and actual field operating experience is provided with 220/500kV voltage control target definite value and adjusting dead band and 10/35kV voltage limit value and the TCR upper lower limit value of exerting oneself respectively by system load flow; Measure and judge 220/500kV and 10/35kV voltage; If 220/500kV voltage is reduced to 0.8 mark the one and breaks down with the next system that is considered as within 3-5 cycle, thereby TCR exerts oneself and reduces to zero immediately and discharge a large amount of capacitive reactive powers with support voltage; If because the normal fluctuation of voltage causes 220/500kV voltage not in the definite value scope, then the variation of at first exerting oneself by TCR is adjusted, TCR then adjusts by automatic switching capacitive compensation branch road after exerting oneself and reaching limit value, wherein the principle of capacitive compensation branch road switching is that 10/35kV voltage reaches higher limit and then can not drop into capacitive branch again, and 10/35kV voltage reaches lower limit then must not excise capacitive branch; If 220/500kV voltage in the definite value scope and 10/35kV voltage be higher than lower limit, then continue to keep previous running status, otherwise will judge whether slightly to fall 220/500kV voltage control level to guarantee the 10/35kV quality of voltage by expert's handling procedure.

Regulate the dead band in the method for the invention and get the peaked 1.15-1.3 of a capacitive compensation branch road of switching 220/500kV change in voltage doubly, the interval that 220/500kV voltage control target definite value plus-minus is regulated the dead band acquisition promptly is considered as controlled target definite value scope.

10/35kV upper voltage limit value of the present invention is taken as capacitive compensation branch road overvoltage protection definite value and deducts 1.05-1.25 and doubly drop into the maximum that a capacitive compensation branch road 10/35kV voltage may rise; 10/35kV lower voltage limit value is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends.

The adjusting employing 1-5M capacity of exerting oneself of TCR is a unit in the control of the present invention, obtains the capacity of exerting oneself and specifically adjusting every 10-30 TCR second by the Self-adjustment Factor fuzzy controller; In the control is the actual acceptable 220/500kV voltage range of system under the different running method at expert's handling procedure, when 10/35kV voltage is lower than lower limit online judge whether can be in short-term be the needs that cost satisfies 10/35kV voltage slightly to reduce 220/500kV controlled target definite value.

Beneficial effect of the present invention is: TCR type SVC is used for the various complex working conditions of transformer substation voltage control when fully taking into account no separate compensation bus, under the prerequisite that guarantees low-pressure side voltage, regulate and control high side voltage, greatly improve the stability of system, effectively avoided the frequent switching of capacitive compensation branch road simultaneously.TCR is controlled at the Self-adjustment Factor of having introduced in the fuzzy algorithmic approach with the error size linear change, has improved the dynamic property of TCR.Whole control method realizes simple, practical, is very suitable for the application of TCR type SVC in transformer station.

Description of drawings

Fig. 1 is SVC voltage control overall flow figure.

The fuzzy control flow chart of Fig. 2 for TCR is exerted oneself and controls.

Embodiment

Below in conjunction with embodiment and contrast accompanying drawing the present invention is further illustrated.

Embodiment 1:

Referring to Fig. 1, the basic procedure according to TCR type SVC is used for transformer substation voltage control at first is provided with 220/500kV voltage control target definite value and regulates the dead band.Wherein voltage control target definite value mainly requires to be assigned by traffic department according to practical operating experiences and daily system voltage, regulating the dead band then adjusts definite according to operating experience and system, usually get peaked 1.2 times of a capacitive compensation branch roads system of switching 220/500kV change in voltage, 220/500kV voltage control target definite value is added and subtracted respectively and is regulated the interval that the dead band obtains and promptly be considered as controlled target definite value scope, and SVC detects with this and judges that current high side voltage is whether within target zone.Second step was that 10/35kV voltage upper lower limit value and the TCR upper lower limit value of exerting oneself is set.Wherein 10/35kV voltage upper lower limit value is adjusted by operating experience and system and is determined, higher limit is taken as capacitive compensation branch road overvoltage protection definite value and deducts maximum that capacitive compensation branch road 10/35kV voltage may rise of 1.1 times of inputs, and lower limit is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends; TCR exerts oneself upper lower limit value according to system load flow result of calculation and definite in conjunction with the actual conditions of transformer station, its principle is both to have guaranteed that TCR had certain dynamic reactive adjustable range, makes the system failure that SVC whenever can both guaranteed enough idle deposits may occur with reply again.After every definite value setting is finished, controller promptly begins the high and low pressure side real-time voltage that cycle detection is judged system, several logics are controlled below main the branch: (1) is if 220/500kV voltage is higher than controlled target definite value scope, whether judge at first that TCR exerts oneself reaches higher limit, if do not reach the upper limit, then exert oneself by the fuzzy algorithmic approach increase TCR that is with Self-adjustment Factor earlier and satisfy voltage request to it, otherwise judge 10/35kV voltage again, be higher than under the situation of lower limit the excision capacitive branch to meet the demands at it, if 10/35kV voltage is lower than lower limit, for guaranteeing the 10/35kV quality of voltage, SVC will keep current running status;

(2) if 220/500kV voltage in controlled target definite value scope, is then judged 10/35kV voltage again, if it is higher than higher limit, then SVC will keep current running status, otherwise change expert's handling procedure over to.This expert's handling procedure is the actual acceptable 220/500kV voltage range of system under the different running method that obtains by practical operating experiences, can onlinely judge whether can or be necessary in short-term slightly to fall 220/500kV controlled target definite value to be the needs that cost satisfies 10/35kV voltage when 10/35kV voltage is lower than lower limit;

(3), break down with the next system that is considered as if within 5 cycles, be reduced to 0.8 mark the one, thereby TCR exerts oneself and reduces to zero immediately and discharge whole capacitive reactive powers with rapid support voltage if 220/500kV voltage is lower than controlled target definite value scope.Whether otherwise judging that TCR exerts oneself reaches lower limit again; if do not reach lower limit; then exert oneself by the fuzzy algorithmic approach reduction TCR that is with Self-adjustment Factor earlier and satisfy voltage request to it; then judge 10/35kV voltage again if reach lower limit; be lower than at it and drop into capacitive branch under situation of its higher limit to meet the demands; otherwise for guaranteeing the 10/35kV quality of voltage, avoid capacitive branch frequent switching or protection tripping operation, SVC will continue to keep current running status.

Referring to Fig. 2, for finishing the exert oneself fuzzy controller flow chart of the band Self-adjustment Factor of adjusting function of TCR shown in Figure 1.Controller adopts the single argument two-dimensional structure, changes e with the error e between 220/500kV voltage definite value and the measured value and its error.As input, K1, K2 as rule of thumb with the obfuscation factor of the determined sum of errors error rate of measured data signal, by carrying out obfuscation after them, obtain fuzzy control table separately, promptly obtain corresponding fuzzy variable grade point

With

Their domain grade classification is identical in the middle of this.For obtaining corresponding fuzzy control quantity, introduced Self-adjustment Factor a, control question blank and can be expressed as this moment

$\begin{array}{cccc}\underset{~}{Q}=-[a\underset{~}{E}+(1-a)\underset{~}{\mathrm{Ec}}]& a=\left[(a_H-a_L)\right|E\left|\right]/m+a_L& 0\≤a_L\≤a_H\≤1& a\∈(a_L,a_H)\end{array}$

M is the maximum in the domain grade in the formula, value and the systematic error absolute value of the adjustment factor a that introduces | the linear insertion relation of E|, be equivalent to and in whole domain, adjust the error weight coefficient automatically, satisfy the characteristics that the different error amount stages require different numerical value by error size.By the control variables grade point of above step through the fuzzy reasoning acquisition Ambiguity solution is after by after the output controlled quentity controlled variable fuzzy decision factor K 3 that obtains according to actual conditions and experience, the Q that obtains at last is the controlled quentity controlled variable of TCR volume change, this controlled quentity controlled variable is converted into the TCR trigger angle by inquiry TCR capacity with the corresponding form of TCR trigger angle, thereby the output of regulating and controlling TCR is idle.Wherein TCR capacity and the corresponding form of TCR trigger angle are according to formula $Q=U_L^2\frac{1}{X_L}(2-\frac{2\mathrm{\θ}}{\mathrm{\π}}+\frac{1}{\mathrm{\π}}\sin 2\mathrm{\θ})$ Obtain, Q is the TCR capacity in the formula, U _LBe system line voltage, X _LBe the single phase impedance of TCR branch road Controlled Reactor, θ is the TCR trigger angle.

Embodiment 2:

Present embodiment is regulated the dead band and is got peaked 1.15 times of a capacitive compensation branch road of switching 220/500kV change in voltage, and the interval that 220/500kV voltage control target definite value plus-minus is regulated the dead band acquisition promptly is considered as controlled target definite value scope.Deduct maximum that capacitive compensation branch road 10/35kV voltage may rise of 1.25 times of inputs and be taken as capacitive compensation branch road overvoltage protection definite value in 10/35kV upper voltage limit value.Limit value is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends.If 220/500kV voltage is lower than controlled target definite value scope, break down with the next system that is considered as if within 3 cycles, be reduced to 0.8 mark one, thereby TCR exerts oneself and reduces to zero immediately and discharge whole capacitive reactive powers with rapid support voltage.It is a unit that the exerting oneself of TCR adjust to be adopted the 2.5M capacity, obtains the capacity of exerting oneself and should specifically adjust every 15 seconds TCR by the Self-adjustment Factor fuzzy controller.

Other method and step are with embodiment 1.

Embodiment 3:

Present embodiment is when measuring judgement 220/500kV and 10/35kV voltage, and 220/500kV voltage is considered as the system failure being reduced to 0.8 mark within 3 cycles below one, and TCR exerts oneself and reduces to zero immediately, discharges all capacitive reactive powers to support voltage.Regulate the dead band and get peaked 1.3 times of a capacitive compensation branch road of switching 220/500kV change in voltage, the interval that 220/500kV voltage control target definite value plus-minus is regulated the dead band acquisition promptly is considered as controlled target definite value scope.10/35kV upper voltage limit value is taken as capacitive compensation branch road overvoltage protection definite value and deducts maximum that capacitive compensation branch road 10/35kV voltage may rise of 1.15 times of inputs; 10/35kV lower voltage limit value is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends.It is a unit that the exerting oneself of TCR adjust to be adopted the 4M capacity, obtains the capacity of exerting oneself and should specifically adjust every 10 seconds TCR by the Self-adjustment Factor fuzzy controller.Other method and step are poly-identical with embodiment 1.

Embodiment 4:

Present embodiment is when measuring judgement 220/500kV and 10/35kV voltage, and 220/500kV voltage is considered as the system failure being reduced to 0.8 mark within 3-5 the cycle below one, and TCR exerts oneself and reduces to zero immediately, discharges all capacitive reactive powers to support voltage.Regulate the dead band and get peaked 1.2 times of a capacitive compensation branch road of switching 220/500kV change in voltage, the interval that 220/500kV voltage control target definite value plus-minus is regulated the dead band acquisition promptly is considered as controlled target definite value scope.10/35kV upper voltage limit value is taken as capacitive compensation branch road overvoltage protection definite value and deducts maximum that capacitive compensation branch road 10/35kV voltage may rise of 1.25 times of inputs; 10/35kV lower voltage limit value is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends.It is a unit that the exerting oneself of TCR adjust to be adopted the 3M capacity, obtains the capacity of exerting oneself and should specifically adjust every 20 seconds TCR by the Self-adjustment Factor fuzzy controller.Other method and step are poly-identical with embodiment 1.

Embodiment 5:

Present embodiment is when measuring judgement 220/500kV and 10/35kV voltage, and 220/500kV voltage is considered as the system failure being reduced to 0.8 mark within 3-5 the cycle below one, and TCR exerts oneself and reduces to zero immediately, discharges all capacitive reactive powers to support voltage.Regulate the dead band and get the peaked 1.15-1.3 of a capacitive compensation branch road of switching 220/500kV change in voltage doubly, the interval that 220/500kV voltage control target definite value plus-minus is regulated the dead band acquisition promptly is considered as controlled target definite value scope.10/35kV upper voltage limit value is taken as capacitive compensation branch road overvoltage protection definite value and deducts 1.05-1.25 and doubly drop into the maximum that a capacitive compensation branch road 10/35kV voltage may rise; 10/35kV lower voltage limit value is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends.It is a unit that the 1-5M capacity is adopted in the adjustment of exerting oneself of TCR, and obtains the capacity of exerting oneself and should specifically adjust every 10-30 TCR second by the Self-adjustment Factor fuzzy controller.Other method and step are poly-identical with embodiment 1.

Claims (4)

1. TCR type SVC voltage control method that is used for transformer station may further comprise the steps:

1.1 220/500kV voltage control target definite value is set and regulates the dead band;

1.2 10/35kV voltage upper lower limit value and the TCR upper lower limit value of exerting oneself is set;

Judge 220/500kV and 10/35kV voltage 1.3 measure:

1.31 220/500kV voltage is considered as the system failure being reduced to 0.8 mark within 5 cycles below one, TCR exerts oneself and reduces to zero immediately, discharges all capacitive reactive powers to support voltage;

1.32 220/500kV voltage is higher than controlled target definite value scope, increasing TCR according to algorithm exerts oneself until its upper limit, as still being higher than target definite value scope, being not less than under the situation of lower limit excision capacitive compensation branch road automatically at 10/35kV voltage, otherwise keeping current running status;

220/500kV voltage is lower than controlled target definite value scope, reducing TCR according to algorithm exerts oneself until its lower limit, as still being lower than target definite value scope, not being higher than at 10/35kV voltage and dropping into the capacitive compensation branch road under the situation of higher limit automatically, otherwise keep current running status;

220/500kV voltage is in the controlled target definite value scope and 10/35kV voltage is higher than lower limit, continue to keep current running status, otherwise judge whether to need to reduce 220/500kV voltage control level to guarantee the 10/35kV quality of voltage by expert's handling procedure, regulate the dead band and get the peaked 1.15-1.3 of a capacitive compensation branch road of switching 220/500kV change in voltage doubly, the interval that 220/500kV voltage control target definite value plus-minus is regulated the dead band acquisition promptly is considered as controlled target definite value scope.

2. the TCR type SVC voltage control method that is used for transformer station according to claim 1 is characterized in that: 10/35kV upper voltage limit value is taken as capacitive compensation branch road overvoltage protection definite value and deducts 1.05-1.25 and doubly drop into the maximum that a capacitive compensation branch road 10/35kV voltage may rise; 10/35kV lower voltage limit value is taken as transformer station's acceptable 10/35kV voltage minimum of normal operation and adds the maximum that capacitive compensation branch road 10/35kV voltage of excision descends.

3. according to claim 1 or the 2 described TCR type SVC voltage control methods that are used for transformer station, it is characterized in that: it is a unit that the 1-5M capacity is adopted in the adjustment of exerting oneself of TCR, obtain the capacity of exerting oneself and specifically to adjust every 10-30 TCR second by the Self-adjustment Factor fuzzy controller, be converted into the TCR trigger angle by inquiry TCR capacity with the corresponding form of TCR trigger angle, thereby the control TCR variation of exerting oneself, wherein TCR capacity and the corresponding form of TCR trigger angle are according to formula

Obtain, Q is the TCR capacity in the formula, U _LBe system line voltage, X _LBe the single phase impedance of TCR branch road Controlled Reactor, θ is the TCR trigger angle.

4. the TCR type SVC voltage control method that is used for transformer station according to claim 3, it is characterized in that: the Self-adjustment Factor in the fuzzy controller is taken as a=[(a _H-a _L) | E|]/m+a _L, 0≤a _L≤ a _H≤ 1, a ∈ (a _L, a _H), a is a Self-adjustment Factor in the formula, a _LAnd a _HBe the Self-adjustment Factor high-low limits, E is the 220/500kV voltage error after the obfuscation, and m is the value in the domain.

Images