CN100413180C - Controlling regulator for joint running of spepped series power station - Google Patents

Abstract

The present invention belongs to the technical field of the operation control of a hydraulic power station. The present invention is characterized in that the regulator assists with the sum of a part of state mete power value of the step electric station on the basis that the relative value of rotary speed offset is introduced for regulation, the comparison is carried out, the result is used as the control quantity of the system, and the residual error of a steady state of a resetting section (practical differential section). the product of the offset relative values of the forever state rotating difference coefficient of the step electric station system, and the sum (namely total power) of the power of all operating machine sets in the step series electric station system is compared with the offset relative value of the rotary speed; the comparative value is used for determining the static error of the rotary speed; consequently, the total power of the step series electric station corresponds to the static state frequencies (rotary speeds) of a combined regulating system one by one for realizing the load distribution of the series electric station by a power system. The output distribution of the machine set is realized by that the flow balance regulation between stations is ensured.

Description

Controlling regulator for joint running of spepped series power station

Technical field

The invention belongs to hydroelectric station operation control technology field.

Background technology

At present, the regulating system in hydroelectric station all adopts the PID speed regulator, load in electric power system changes, regulates when deviation appears in generating unit speed, corresponding change unit flow, make the hydraulic turbine Hydraulic Moment and the generator load moment of resistance after the change reach new balance, to keep frequency (generating unit speed) within the limits prescribed.

Conventional power plant is because the preceding storage capacity in station is big, when being subjected to load and disturbing laggard line frequency to regulate, can think that reservoir level is constant, adopt the PID speed regulator, according to load variations, regulate the wicket gates of unit, hydraulic turbine discharge is changed, to keep generating unit speed stable, guarantee that frequency stabilization is in the scope that electric power system requires.Because before the power station bigger buffering storage capacity is arranged, the adjusting in power station is very little for the influence on system operation in other power stations in the basin, as long as rational management, each power station can make full use of the hydraulic power potentials safe operation.

Along with development of the West Regions and the nation-building growth to energy demand, hydroelectric resources is all being developed energetically in each river basin in southwest in recent years.At present in China, planned on the Xi Bu river that particularly not regulating storage capacity between some power stations only is connected with pipeline with open channel or regulates the very little step hydropower station of storage capacity, power stations at different levels influence greatlyyer to each other in such operation of power station system, can be called semi-open type step series connection power station.Because the scalable storage capacity between the power station is little or do not have scalable storage capacity, not only to carry out the adjusting of frequency after disturbing being subjected to loading, the flow equilibrium that also will connect between the power station is regulated.

Little or do not regulate the semi-open type step series connection power station of storage capacity for regulating storage capacity before the station, adopt the regulative mode of conventional hydropower station, when PID speed regulator control unit is adopted independently in power stations at different levels, because the PID speed regulator can only feed back generating unit speed, therefore can only under the situation of generating unit speed generation deviation, carry out rotational speed regulation, but can not contribute for the flow equilibrium of system.Though this control mode can be adjusted rotating speed in the short time, can not guarantee that the total flow in power stations at different levels equates, can not change the unbalanced situation of flow between the station.In the case, because storage capacity is little or do not regulate storage capacity between the station, the reservoir between the power station or the water level of open channel cause the water surface not stablize because of the permanent disequilibrium of its turnover flow, to occur continuing slowly to descend or rise, its speed depends on difference in flow between the upstream and downstream power station and the size of regulating storage capacity, cause the most at last a standing reservoir or open channel overflow occurs or leaks the situation at the end, can not make power station stable operation.Because the particularity of target is regulated in such step series connection power station, promptly be subjected to not only will carrying out frequency adjustment after load disturbs in the power station, the flow equilibrium that also will connect between the power station is regulated, and traditional PID regulative mode is single input/single output closed-loop control system, in this system, only be concerned about an output amount of result (amount of being conditioned), therefore, the way that adopts traditional PID control speed regulator only to feed back rotating speed can not satisfy the stability of such series connection electric power station system and the requirement of dynamic quality.

The present invention promptly is in the semi-open type step series connection system combined operation in power station, unites under the situation of adjusting, with the series connection station group serves as that integral body transmits electric power to external power grid, set up the cooperation controlled adjuster in semi-open type step series connection power station, when extraneous network load disturbs, regulate flow equilibrium between generating unit speed and station simultaneously, realize the stable operation of system.

Summary of the invention

The object of the present invention is to provide a kind of adjuster that can carry out the step series connection power station cooperation control that Flow-rate adjustment and rotational speed regulation distribute with the total load that can make whole series connection station group simultaneously on flow equilibrium basis between the station.

The invention is characterized in:

Controlling regulator for joint running of spepped series power station, it is characterized in that, this adjuster is arranged on the miniature digital computer or the digital integrated circuit chip that are used for the computer set adjustment law on each unit i in the described step series connection power station, if n is total platform number of unit in this step series connection power station, i is the unit sequence number, on described each digital integrated circuit or digital computer, be provided with successively: the 1st comparator, the link of differentiating, the 2nd comparator, the 1st integral operation link, the 3rd comparator and the 2nd integral operation link, wherein:

The 1st comparator has n, and this comparator has following two input signals:

X, rotating speed deviation relative value, i.e. the ratio of unit rated speed when the deviate of unit rated speed is moved with respect to systematic steady state during generating unit speed and systematic steady state operation is by the frequency measurement circuit acquisition of unit;

U _i, the control variables of unit i is the weighted sum that this unit is regulated the quantity of state of required feedback, i=1 ..., n, express with following formula:

$U_i=\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{K}_{\mathrm{ij}}{u}_{\mathrm{ij}}$

Wherein, u _IjBe the feedback states amount of water level of open channel deviation relative value or other appointments between regulating reservoir water level deviation relative value or surge shaft water level deviation relative value or station between the rotating speed deviation relative value x of unit i or servomotor deviation of stroke relative value or station, K _IjBe corresponding each opposite state amount u _IjThe feedback factor of setting, j=1 ..., m, m are the quantity of state number corresponding to the required feedback of i unit;

The link of differentiating has n, and this link input links to each other with the output of corresponding the 1st comparator, to carry out

Computing, wherein, K _DiBe the involution piece gain of unit i, T _DiBe the involution piece time constant of unit i, unit is second, and the described link of differentiating is an involution piece, and in order to remove the stable state offset in the output of the 1st comparator, this involution piece is output as 0 when arriving stable state;

The 2nd comparator has n, and this comparator has following three input signals:

X, i.e. rotating speed deviation relative value;

The output valve of the aforementioned link of differentiating accordingly;

b _pP, wherein, P is the deviation relative value of these all operation aggregate capacities of step series connection power station, $P=(\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{p}_i-p)/p,$ The gross power that is whole step series connection power station operation unit is connected the deviate of the specified gross power p of electric power station system with respect to the connect ratio of the specified gross power p of electric power station system of whole step with whole step, the power measurement loop by unit obtains; p _iBe this series connection power station i platform unit output, b _pFor the slip of the attitude forever coefficient of whole step series connection power station combined operation system, be a set point.

The output of described the 2nd comparator is that the aforementioned corresponding link output of differentiating deducts x, deducts b again _pP and obtain poor;

The 1st integral operation link has n, and this link input links to each other with the output of corresponding the 2nd comparator, and input signal is carried out

Computing, wherein, T _MiBe the time constant of the hydraulic pressure amplifying device of unit i, unit is second;

The 3rd comparator has n, and this comparator input terminal links to each other with the output of corresponding the 1st integral operation link;

The 2nd integral operation link has n, and this link input links to each other with the output of corresponding the 3rd comparator, and input signal is carried out Computing, wherein, T _YiBe the servomotor time constant of unit i, unit is second, and output signal then feeds back to the input of corresponding the 3rd comparator, y _iBeing the servomotor deviation of stroke relative value of unit i, promptly is the deviation relative value of servomotor stroke of the i platform unit of fiducial value with the range of i platform unit servomotor, i=1 ..., n.

In order to verify the working control effect of designed controller to system, its cooperation controlled adjuster has been set up according to the present invention in certain semi-open type step series connection power station, and with the design controlled adjuster be embedded in the non-linear emulation of system, simulation calculation result proves that this adjuster can realize the stable operation in power station of connecting, and makes the flow system flow balance in the Adjustment System rotating speed.

Description of drawings

Fig. 1, step series connection power station cooperation regulating and controlling theory diagram

Fig. 2, the power station static characteristic

Fig. 3, involution link calcspar

Fig. 4, certain step hydropower station water-carriage system is arranged schematic diagram

Fig. 5, power station generating unit speed-time plot

Fig. 6,1# unit flow-time plot

Fig. 7,3# unit flow-time plot

Fig. 8,5# unit flow-time plot

Fig. 9, primary power station upstream surge shaft water level-time plot

Figure 10, second cascade hydropower station upstream collection chamber water level-time plot

Figure 11, second cascade hydropower station upstream regulation pool water level-time plot

Figure 12, second cascade hydropower station upstream surge shaft water level-time plot

Figure 13, upstream, three grades of power stations collection chamber water level-time plot

Figure 14, three grades of power station upstream regulation pool water level-time plots

Figure 15, upstream, three grades of power stations surge shaft water level-time plot

Embodiment

Semi-open type step series connection electric power station system because the scalable storage capacity between some power station is very little or do not have scalable storage capacity, not only needs to carry out the adjusting of frequency after disturbing being subjected to loading, and the flow equilibrium that also must connect between the power station is regulated.Such series connection electric power station system is adopted conventional hydraulic turbine PID speed regulator, can not make its stable operation, thus such series connection station group since the Hydraulic Power System contact closely, must cooperation, and will unite adjusting.The i.e. cooperation controlled adjuster in the semi-open type step series connection power station of setting up by the present invention, realize that external power grid requires a total load to whole series connection station group, and every load that unit is born distributes on the basis that guarantees flow equilibrium between the station by adjuster.

Certain semi-open type step series connection power station is made of three grades of impact type power stations, collection chamber and regulating reservoir are arranged between the power station, by the inverted-siphon pipeline or do not have and press tailrace tunnel to connect, every grade of power station is provided with the upstream surge shaft, the water-carriage system of step hydropower station is arranged sketch as shown in Figure 4, and each power station unit nominal parameter sees Table 1.

Table 1 power station at different levels unit nominal parameter

The calcspar of semi-open type controlling regulator for joint running of spepped series power station as shown in Figure 1.

Suppose in the step series connection power station that the machine number of organizing a performance is n, below the variable in the adjuster calcspar of Fig. 1 described:

X-rotating speed deviation relative value is a fiducial value with the unit rated speed promptly, the relative value of the deviation of generating unit speed during the operation of generating unit speed and systematic steady state, and the frequency measurement loop by unit records;

The deviation relative value of all operation aggregate capacities of P-step series connection power station, the deviate of the gross power that is whole step series connection power station operation unit and system specified gross power is with respect to the connect ratio of the specified gross power of electric power station system of whole step, and the power measurement loop by unit obtains;

U _iThe control variables of-Di i platform unit is the weighted sum of required feedback states amount. $U_i=\underset{j=1}{\overset{m}{\mathrm{\Σ}}}{K}_{\mathrm{ij}}{u}_{\mathrm{ij}},$ Wherein, u _IjBe unit

The feedback states amount of water level of open channel deviation relative value or other appointments between regulating reservoir water level deviation relative value or surge shaft water level deviation relative value or station between the rotating speed deviation relative value of i or servomotor deviation of stroke relative value or station, K _IjBe corresponding u _IjFeedback factor, j=1,2 ... m, m are the quantity of state number of the required feedback of corresponding i platform unit, and the quantity of state of required feedback and its feedback factor are determined according to actual conditions.

y _i-Di i platform unit servomotor deviation of stroke relative value promptly is the deviation relative value of servomotor stroke of the i platform unit of fiducial value with the range of i platform unit servomotor, i=1, and 2,3 ... n;

b _p-be the coefficient of transmission link, be called the coefficient of attitude slip forever, the static permanent speed regulation in reflection power station.

Unit is when operation of power networks, and adjuster need have certain clear and definite its sharing of load of static permanent speed regulation ability, and the unit permanent speed regulation satisfies x in the conventional hydropower station _i=-b _Ply _l, x wherein _l, y _l, b _PlBe respectively rotating speed, guide vane opening deviation relative value and the coefficient of attitude slip forever of each unit, l is the machine group #, and every unit all is provided with the coefficient of attitude slip forever.But, during the cooperation of step series connection power station, to do as a wholely to the external power grid power output, the power station power of the assembling unit is distributed on the basis of flow equilibrium between the station, and the relative value of rated speed is identical separately with respect to it for each generating unit speed.If given according to a conventional method unit permanent speed regulation, then each unit guide vane opening will be limited by rotating speed according to permanent speed regulation in the combined operation system of step series connection power station, regulate contradicting with the flow equilibrium between the station, cause the system can not stable operation.Therefore, in the combined operation system of step series connection power station, the present invention has provided the slip of the attitude forever coefficient at whole power station combined operation system, and x=-b presses in system during cooperation _pP regulates power.Thereby guaranteed that the power station has rational sharing of load when normal operation, that is be make the power station unit when stable state rotating speed and the power station gross power between have relation one to one, as shown in Figure 2.

For convenience of description, below provide the symbol definition of some quantity of states.y ₁, y ₂, y ₃, y ₄, y ₅, y ₆Be respectively the deviation relative value of the servomotor stroke of each unit, H _S1, H _S4, H _S7Be respectively one-level, secondary, three grades of power station upstream surge shaft water level deviation relative values separately, H _S2, H _S3Be second cascade hydropower station upstream collection chamber, regulating reservoir water level deviation relative value, because the collection chamber of second cascade hydropower station upstream, regulating reservoir connect by short siphon piping, collection chamber, regulating reservoir water-level fluctuation are approaching, so only adopt the water level deviation relative value H of regulating reservoir _S3, H _S5, H _S6Be respectively upstream, three grades of power stations collection chamber, regulating reservoir water level deviation relative value, water level deviation relative value is the ratio of the datum level of the variation of each surge shaft, collection chamber, regulating reservoir water level and setting, and x represents generating unit speed deviation relative value.

Quantity of state that each unit need feed back and corresponding feedback factor thereof see Table 2, in the table, and U ₁, U ₂, U ₃, U ₄, U ₅, U ₆Be respectively the controlled quentity controlled variable input of each unit, take advantage of the feedback factor addition to obtain by the feedback states amount of each unit.

Table 2 system mode feedback quantity dimensionality reduction result

K _DiThe gain of-Di i platform unit involution piece;

T _Di-Di i platform unit involution piece time constant, unit is s;

The control variables U of power station unit controlled adjuster is that the linear combination by a plurality of quantity of states forms, and for the introducing of avoiding quantity of state produces bigger static receiver error, adopts involution link commonly used on the engineering to remove its stable state offset.The involution link is actually an actual differentiation element, and its calcspar as shown in Figure 3.When reaching stable state, the involution link is output as 0, when input changes acutely, plays proportional component.

T _Mi-Di i platform unit hydraulic pressure amplifying device time constant, unit is s;

T _Yi-Di i platform unit servomotor time constant, unit is s;

Can partly ask its transfer function to be to the adjusting of every unit according to the adjuster calcspar:

$\frac{K_{\mathrm{Di}}s}{1+T_{\mathrm{Di}}s}(U_i-x)-b_{p}P-x=T_{m}s(1+T_{\mathrm{yi}}s)y_i$

Through the Laplace inverse transformation, adjusted device equation is again:

$A_i\frac{d^3{y}_i}{{\mathrm{<figure-callout\; id="3"\; label="dt"\; filenames="C20061007624500125.png"\; state="\{\{state\}\}">dt</figure-callout>}}^3}+B_i\frac{d^2{y}_i}{{\mathrm{<figure-callout\; id="2"\; label="dt"\; filenames="C20061007624500121.png"\; state="\{\{state\}\}">dt</figure-callout>}}^2}+C_i\frac{{\mathrm{dy}}_i}{\mathrm{dt}}+b_{p}P+D_i\frac{\mathrm{dx}}{\mathrm{dt}}+x-K_{\mathrm{Di}}\frac{d{U}_i}{\mathrm{dt}}=0$

In the formula, A _i=T _DiT _MiT _Yi, B _i=T _DiT _Mi+ b _pT _DiT _Yi, C _i=b _p(T _Di+ T _Yi)+T _Mi(1+T _Yi), D _i=K _Di+ T _Di

The adjuster of design is embedded in the non-linear simulated program of total system in step series connection power station, total system has been carried out simulation calculation, pipeline, non-pressure tunnel, surge shaft, collection chamber, regulating reservoir, power station unit are all set up Mathematical Modeling according to the design parameter of real system and the nonlinear characteristic of itself and are calculated in the calculating, owing to include non-pressure tunnel in the system, the stable state initial value of system adopts the dead head condition method to calculate.The output of power station of calculating example is 70.128 ten thousand KW, gets rid of 10% load, static permanent speed regulation gets 0.04, the simulation result of this operating mode such as Fig. 5～Figure 15.

Calculating shows, static permanent speed regulation in the power station is 0.04 o'clock, after getting rid of 10% load, adopt adjuster to control, system finally can stablize, but each generating unit speed is a rated speed owing to adjust when sending out rated output 77.92 ten thousand KW in the power station, static permanent speed regulation is taken as 0.04, so when 70.128 ten thousand KW load was sent out in initial operating mode power station, the relative rotation speed of each unit was 1.004, the relative rotation speed steady-state value of each unit is 1.0076 after getting rid of 10% steady load.The steady state deviation of collection chamber, regulating reservoir water level is little between the power station, and control better.Each surge shaft, collection chamber, regulating reservoir water level see Table 3.

Table 3 surge shaft, collection chamber, regulating reservoir water gage

	Initial water level (m)	Peak level (m)	Lowest water level (m)	Final fixed level (m)
					Primary power station upstream surge shaft	2926.491	?2930.809	?2923.661	?2927.124
Second cascade hydropower station upstream collection chamber	2315.487	?2315.534	?2315.364	?2315.468
					Second cascade hydropower station upstream regulation pond	2315.437	?2315.440	?2315.415	?2315.428
Second cascade hydropower station upstream surge shaft	2313.062	?2316.668	?2310.585	?2313.481
					Upstream, three grades of power stations collection chamber	1691.599	?1691.652	?1691.531	?1691.626
Upstream regulation pond, three grades of power stations	1691.594	?1691.623	?1691.586	?1691.622
					Upstream, three grades of power stations surge shaft	1688.122	?1693.067	?1685.288	?1688.777

Claims (1)

1. controlling regulator for joint running of spepped series power station, it is characterized in that, this adjuster is arranged on the miniature digital computer or the digital integrated circuit chip that are used for the computer set adjustment law on each unit i in the described step series connection power station, if n is total platform number of unit in this step series connection power station, i is the unit sequence number, on described each digital integrated circuit or digital computer, be provided with successively: the 1st comparator, the link of differentiating, the 2nd comparator, the 1st integral operation link, the 3rd comparator and the 2nd integral operation link, wherein:

The 1st comparator has n, and this comparator has following two input signals:

X, rotating speed deviation relative value, i.e. the ratio of unit rated speed when the deviate of unit rated speed is moved with respect to systematic steady state during generating unit speed and systematic steady state operation is by the frequency measurement circuit acquisition of unit;

U _i, the control variables of unit i is the weighted sum that this unit is regulated the quantity of state of required feedback, i=1 ..., n, express with following formula:

$U_i=\underset{j=1}{\overset{m}{\mathrm{\&Sigma;}}}{K}_{\mathrm{ij}}{u}_{\mathrm{ij}}$

Wherein, u _IjBe the feedback states amount of water level of open channel deviation relative value or other appointments between regulating reservoir water level deviation relative value or surge shaft water level deviation relative value or station between the rotating speed deviation relative value x of unit i or servomotor deviation of stroke relative value or station, K _IjQuantity of state u for corresponding each feedback _IjThe feedback factor of setting, j=1 ..., m, m are the quantity of state number corresponding to the required feedback of i unit;

The link of differentiating has n, and this link input links to each other with the output of corresponding the 1st comparator, to carry out

Computing, wherein, K _DiBe the involution piece gain of unit i, T _DiBe the involution piece time constant of unit i, unit is second, and the described link of differentiating is an involution piece, and in order to remove the stable state offset in the output of the 1st comparator, this involution piece is output as 0 when arriving stable state;

The 2nd comparator has n, and this comparator has following three input signals:

X, i.e. rotating speed deviation relative value;

The output valve of the aforementioned link of differentiating accordingly;

b _pP, wherein, P is the deviation relative value of these all operation aggregate capacities of step series connection power station, $P=(\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}{p}_i-p)/p,$ The gross power that is whole step series connection power station operation unit is connected the deviate of the specified gross power p of electric power station system with respect to the connect ratio of the specified gross power p of electric power station system of whole step with whole step, the power measurement loop by unit obtains; p _iBe this series connection power station i platform unit output, b _pFor the slip of the attitude forever coefficient of whole step series connection power station combined operation system, be a set point.

The output of described the 2nd comparator is that the aforementioned corresponding link output of differentiating deducts x, deducts b again _pP and obtain poor;

The 1st integral operation link has n, and this link input links to each other with the output of corresponding the 2nd comparator, and input signal is carried out

Computing, wherein, T _MiBe the time constant of the hydraulic pressure amplifying device of unit i, unit is second;

The 3rd comparator has n, and this comparator input terminal links to each other with the output of corresponding the 1st integral operation link;

The 2nd integral operation link has n, and this link input links to each other with the output of corresponding the 3rd comparator, and input signal is carried out Computing, wherein, T _YiBe the servomotor time constant of unit i, unit is second, and output signal then feeds back to the input of corresponding the 3rd comparator, y _iBeing the servomotor deviation of stroke relative value of unit i, promptly is the deviation relative value of servomotor stroke of the i platform unit of fiducial value with the range of i platform unit servomotor, i=1 ..., n.

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