JP2013062953A - Power system power demand controller and power system power demand control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the residual control in the intermediate period region of a control period by EDC and LFC, and to reduce total power generation cost.SOLUTION: A load frequency controller 100 acquires the imbalance amount of power demand in a power system 42 every several seconds, for example, and outputs an LFC command value 11, as a control amount for eliminating the imbalance, to a generator. An economical load distribution controller 200 calculates the base generation power of each generator so that the total power generation cost in the power system 42 decreases, based on a preset prediction value of power demand in the power system 42. An economical load redistribution controller 300 acquires all or some of the control amounts calculated by the load frequency controller 100 every several tens of second, for example, calculates an economical load distribution correction amount on the basis of the control amount thus acquired, corrects the base generation power of the generator by the correction amount, and outputs the economical load distribution correction amount, as an EDC command value 33, to the generator.

Description

  The present invention relates to a power system power supply / demand control apparatus and a power system power supply / demand control method for maintaining a balance between a load change of a consumer that changes every moment in a power system and a supply / demand balance of total power generated by a generator.

  In an electric power system that supplies electric power from generators of a plurality of power plants to loads of a plurality of consumers, supply and demand control is performed in order to maintain a balance of power supply and demand. Supply and demand control is control for matching the amount of power generation with a load that fluctuates from time to time, and the control is EDC (Economic Load Dispatching) that is performed at time intervals of a long period (several minutes to several tens of minutes). Control: economic load distribution control) and LFC (Load Frequency Control) performed at time intervals of a short period (several seconds to several tens of seconds).

  In general, in EDC, a generator that generates power is determined in accordance with the power demand of the entire power system so that the total power generation cost of the generator in the power system is minimized, and the optimal output generation amount distribution is determined. It is determined. Then, at the power plant, a planned operation is performed according to, for example, a daily load curve determined based on the optimum output distribution. On the other hand, in LFC, the power grid power supply and demand control device detects the supply and demand imbalance from the detected values of the frequency and the interconnection flow, and supplies the power supply and demand to each power plant based on the detected supply and demand imbalance. The generated power adjustment command (LFC command) is issued to eliminate the imbalance.

  Normally, LFC does not control power generation costs, so if the power grid power supply / demand control device increases the number of generators and the amount of power generated by the LFC, the same amount of generated power can be obtained only by EDC. The total power generation cost will increase compared with the case where supply and demand control is performed. Therefore, in order to reduce the total power generation cost, it is only necessary to reduce the output adjustment amount that can be controlled by the LFC. However, in that case, it may be difficult to control power supply and demand.

  For example, if unpredictable demand fluctuations continue for a long period, the power grid power supply and demand controller will use up the output adjustment amount that can be controlled by the LFC due to the imbalance in supply and demand until then, It may be slightly. In such a case, if an unpredictable demand fluctuation occurs, the power grid power supply and demand control device cannot issue an LFC control command corresponding to the demand fluctuation.

  This means that conventional EDC and LFC supply / demand control alone cannot sufficiently respond to various supply / demand fluctuations in electric power, and in particular, the intermediate period of the control cycle of EDC long cycle control and LFC short cycle control. This means that there is a problem in the control method in the area. However, it is difficult to say that this problem has been sufficiently studied and addressed in the past.

  By the way, in Patent Document 1, AR (Area Requirement) is classified for each periodic component, and the fluctuation component of the AR is shared between the hydroelectric generator and the thermal power generator for each change speed. A control method is adopted in which the periodic component is shared by EDC control. However, in Patent Document 1, since control in the intermediate period region of the control period of LFC and EDC is ambiguous, sufficient control responsiveness cannot be obtained. That is, since an imbalance in supply and demand due to unpredictable demand fluctuations in the power system appears as fluctuations in the system frequency, it is necessary to quickly resolve the imbalance in supply and demand and return the system frequency to the reference frequency. In the invention described in (1), since supply and demand control in the intermediate period region between the EDC and LFC regions is not sufficient, it is difficult to quickly eliminate the supply and demand imbalance.

  Patent Document 2 discloses an example of a supply and demand control method in an intermediate period region between LFC and EDC. That is, according to Patent Document 2, the power grid power supply and demand control device classifies generators into three groups based on output fluctuation delays, and uses a low pass filter (LPF) to provide AR (regional requirements). 3) extract the three fluctuation components that the generators of each group can follow, and distribute and calculate the fluctuation components to each group. The PID (Proportional, Integral and Differential) control unit controls the LFC command and EDC of each generator. A correction request command is output. That is, the control residual of LFC control is to be corrected by EDC control.

  However, in the supply and demand control method described in Patent Document 2, at least three generators having different response speeds are required as generators to be subjected to LFC, and further, one generator to be subjected to LFC is one. When it is biased to the group, it tends to be unable to follow fluctuations in supply and demand, resulting in a problem that it is not possible to increase the number of generators subject to EDC considering economic operation.

JP 2002-209336 A JP 2007-306770 A

  FIG. 2 is a diagram illustrating an example of a general supply and demand control mechanism in a conventional power system. Here, in accordance with the concept of supply and demand control in the conventional power system, the reason why control residue occurs in the intermediate period region of the EDC and LFC control periods will be described.

  As shown in FIG. 2, a conventional power system power supply and demand control device 500 is installed in, for example, a central power supply command station, and controls a generator output control device 40 that controls the output of a generator 41, a power system 42, and It is connected to the interconnection line 44 connected to the other company power system 45. The power system power supply and demand control device 500 includes a load frequency control device 100 that outputs the LFC command value 11 for the generator 41 via the generator output control device 40, and an economic load distribution control device that outputs the EDC command value 33. 200. In the present specification, the power system 42 includes a plurality of generators 41 and a plurality of loads 43 connected to the power system 42.

  Here, the load frequency control device 100 acquires the grid frequency 1 and the grid line flow 3 measured by the power system 42 and the grid line 44, respectively, and the power demand value 21 that changes from time to time in the power system 42. , A fluctuation in demand error that cannot be predicted is calculated, and the LFC command value 11 for the generator 41 corresponding to the fluctuation in demand error is output to the generator output control device 40. At this time, it is arbitrarily determined by an operator such as a central power station which LFC command value 11 is output to the generator output control device 40 of which generator 41.

  Further, the economic load distribution control device 200 outputs an EDC command value 33 for the generator 41 to the generator output control device 40 based on the preset demand prediction value 22. In this case as well, as in the case of the LFC command value 11, the operator of the central power station or the like arbitrarily determines which of the generators 41 outputs the EDC command value 33 to the generator output control device 40. Has been. However, the generator 41 that is the output target of the LFC command value 11 and the generator 41 that is the output target of the EDC command value 33 are not necessarily the same.

  In the power system power supply and demand control apparatus 500 configured as described above, the control of the demand error from the EDC command value 33 output from the economic load distribution control apparatus 200 is performed by the economic load distribution control apparatus 200. Until 33 is output, everything is controlled by the LFC command value 11 by the load frequency control device 100.

  That is, the load frequency control device 100 continues to output the LFC command value 11 to the generator output control device 40 of the generator 41 in order to eliminate the supply and demand imbalance due to the demand error of EDC. Therefore, before the supply-demand imbalance due to the demand error is resolved, a situation in which the supply-demand imbalance further increases occurs in the electric power system 42, and the load frequency control device 100 generates power for output of the LFC command value 11. When the machine 41 does not have a margin for the output changeable range, the load frequency control device 100 cannot resolve the continuous supply and demand imbalance. This is because the supply-demand imbalance in the supply / demand control by the long-cycle EDC cannot be controlled by the supply-demand control by the short-cycle LFC, in other words, there is a residual control in the intermediate cycle region of the control cycle of the EDC and the LFC. It means that.

  In general, the total power generation cost in the power system 42 while the load frequency control device 100 performs control based on the LFC command value 11 in order to eliminate the imbalance in supply and demand is the same amount of power as the economic load distribution control device. It will be larger than the total power generation cost when 200 controls the amount of power generated by the generator 41.

  As described above, in the conventional power supply and demand control by EDC and LFC, there is a case in which there is a residual control in the intermediate period region part of both control periods, and there is a problem that the total power generation cost increases. Therefore, in order to solve the problems of the prior art, the present invention reduces the remaining control in the intermediate period region portion of the control period by EDC and LFC and can control the total power generation power supply and demand control. An apparatus and a power system supply and demand control method are provided.

  The power grid power supply and demand control apparatus according to the present invention acquires an unbalanced amount of power demand in the power system and calculates a control amount of generated power for eliminating the unbalanced amount for each first time period. The calculated control amount is divided and distributed to the generators belonging to the power system, and the distributed control amount is output as an LFC command value toward the distribution target generator, For each second time period that is longer than the first time period, the total power generation cost of the generators belonging to the power system is small based on the preset predicted value of power demand in the power system and the demand value at that time. The economic load distribution control device for calculating the generator output base command value of each generator, and the same as the second time period or shorter than the second time period and the first time period Time period For each longer third time period, a part or all of the control amount calculated by the load frequency control device is acquired from the load frequency control device, and the economic load distribution correction amount is based on the acquired control amount. The calculated economic load distribution correction amount is divided and distributed to the respective generators according to the power generation costs of the respective generators, and the respective calculated by the economic load distribution control device The generator output base command value of each generator is corrected with the distributed economic load distribution correction amount, and the corrected generator output base command value of each generator is supplied as an EDC command value to each generator. And an economic load redistribution device that outputs the output.

  In the present invention, the EDC command value output to each generator by the economic load redistribution device is an amount obtained by distributing a part or all of the control amount calculated when performing LFC to each generator. Based on the correction. At this time, since the correction amount allocated to each generator takes into account the power generation cost of each generator, the EDC command value output based on the corrected result is the total power generation cost of the generator. Is suppressed.

  The corrected EDC command value is longer than the cycle in which the load frequency control device outputs the LFC command value, and the cycle in which the economic load distribution control device calculates the generator output base command value of each generator. Shorter than. Therefore, the control in the intermediate period region portion of the control cycle by EDC and LFC which has not been sufficiently controlled conventionally is also sufficiently performed, and the residual control in the intermediate period region portion is eliminated or reduced.

  ADVANTAGE OF THE INVENTION According to this invention, while reducing the control remainder in the intermediate period area | region part of the control period by EDC and LFC, the electric power grid electric power supply-and-demand control apparatus and electric power grid supply and demand control method which can suppress total power generation expense are provided. The

The figure which showed the example of the structure of the electric power grid electric power supply-and-demand control apparatus which concerns on the 1st Embodiment of this invention. The figure which showed the example of the mechanism of the general supply-and-demand control in the conventional electric power grid | system. The figure which showed the example of the time chart at the time of the fluctuation | variation of (a) generator output base command value which causes the electric power supply-and-demand fluctuation | variation in an electric power system at the time of (a) generator output base command change. (A) AR, (b) proportional amount, (c) differential amount, (d) integral amount time chart calculated in the power system power supply and demand control device when power supply and demand fluctuations occur in the power system The figure which showed the example. The figure which showed the example of the time chart of (a) LFC control amount and (b) generator output command value which are calculated within an electric power grid electric power supply-demand control apparatus when the supply-demand fluctuation of electric power arises in an electric power grid. The figure which showed the example of the structure of the electric power grid electric power supply-and-demand control apparatus which concerns on the 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a diagram illustrating an example of the configuration of the power system power supply and demand control apparatus according to the first embodiment of the present invention. As shown in FIG. 1, the power grid power supply and demand control device 400 includes a load frequency control device 100, an economic load distribution control device 200, and an economic load redistribution device 300. Here, the economic load redistribution device 300 is not included in the conventional power system power supply and demand control device 500 (see FIG. 2). That is, it is a feature of this embodiment that the power grid power supply and demand control device 400 includes the economic load redistribution device 300.

  Hereinafter, detailed configurations and functions of the load frequency control device 100, the economic load distribution control device 200, and the economic load redistribution device 300 will be described. In the following description, FIG. 2 is referred to as appropriate. In that case, the conventional power system power supply and demand control apparatus 500 in FIG. 2 is replaced with the power system power supply and demand control apparatus 400 according to the present embodiment. To do.

  As shown in FIG. 1, the load frequency control device 100 includes an area request amount calculation unit 5, a differential amount calculation unit 6, a proportional amount calculation unit 7, an integral amount calculation unit 8, an LFC control amount calculation unit 9, and a proportional distribution. A quantity calculation unit 10 is included.

In the load frequency control device 100, the local requirement amount calculation unit 5 firstly has a grid frequency 1 measured by the power grid 42 (see FIG. 2), a preset reference frequency 2, and a link measured by the interconnection line 44. Based on the power line flow 3 and the preset interconnection line planned flow 4, AR (regional demand amount), which is an unbalanced amount of power supply and demand in the power system 42, is calculated according to the following equation (1).
AR (t) = − ΔF · system constant + ΔPt Equation (1)
Where ΔF = system frequency−reference frequency
ΔPt = Interconnection line tidal current-Interconnection line planned tidal current

Next, the differential amount calculation unit 6, the proportional amount calculation unit 7, and the integral amount calculation unit 8 respectively follow the equation (2), the equation (3), and the equation (4) for the differential amount, the proportional amount, and the PID control. Calculate the integration amount.
Differential amount = Gd · (AR (t) −AR (t−1)) Equation (2)
Proportional amount = Gp · AR (t) Equation (3)
Integration amount = Gi · ΣAR (τ) Equation (4)
Here, Gd, Gp, Gi are constants,
Σ represents the total sum from τ = 1 to t.

  Next, the LFC control amount calculation unit 9 calculates the LFC control amount based on the differential amount, the proportional amount, and the integral amount calculated by the differential amount calculation unit 6, the proportional amount calculation unit 7, and the integral amount calculation unit 8, respectively. To do. Here, it is assumed that the LFC control amount is given by the sum of the differential amount, the proportional amount, and the integral amount expressed by Equation (2), Equation (3), and Equation (4).

  Next, the proportional distribution amount calculation unit 10 uses the calculated LFC control amount as an LFC target generator 41 (#i) (i = 1,..., N: where n is the number of generators 41). Proportional distribution is performed in accordance with the LFC adjustment force set for each (however, proportional distribution with upper and lower limit restrictions), and the LFC command value 11 ((i = 1,..., N)) for each generator 41 (#i) #I) (i = 1,..., N) is calculated. Then, the calculated LFC command value 11 (#i) (i = 1,..., N) is output to the respective generator 41 (#i) (i = 1,..., N).

  In FIG. 1, the integration amount calculation unit 8 receives the generator output 20 (#i) (i = 1,..., N) and the output signal from the economic load distribution unit 24. The handling of signals will be described in detail in a modification of the embodiment described later.

  As shown in FIG. 1, the economic load distribution control device 200 includes an economic load distribution control amount calculation unit 23 and an economic load distribution unit 24.

  In the economic load distribution control device 200, the economic load distribution control amount calculation unit 23 calculates an economic load distribution control amount at a future control time based on the power demand value 21 and the demand predicted value 22 at the current time point. Then, the economic load distribution unit 24 uses the calculated economic load distribution control amount for each generator 41 (#i) (#) so that the total power generation cost of all the generators 41 in the power system 42 is minimized. i = 1,..., n).

Here, an outline of an economic load distribution method performed by the economic load distribution unit 24 to minimize the total power generation cost will be described. The power generation fuel cost C _i of the generator 41 (#i) (i = 1,..., N) in the power system 42 is calculated by the following equation (5).
C _i = a _i · P _i ² + b _i · P _i + c _i Formula (5)
Here, _{P i} is power generation amount of the generator 41 (#i)
a _i , b _i , and c _i are the fuel characteristic coefficients of the generator 41 (#i).

At this time, the proportional distribution ratio of the economic load distribution amount to the generator 41 (#i) (i = 1,..., N) is calculated by the following equation (6).
Proportional distribution ratio = 2 · a _i · P _max + b _i formula (6)
Here, P _max is the maximum value of P _i (i = 1,..., N).

  This proportional distribution ratio represents the incremental fuel cost of the generated fuel cost with respect to the amount of change in the generated power of the generator 41 (#i) (i = 1,..., N). It is a generator with low fuel cost.

  The economic load distribution unit 24 calculates a command value of generated power for each generator 41 (#i) (i = 1,..., N) using the proportional distribution ratio calculated by the equation (6). This generated power command value corresponds to the EDC command value 33 output by the conventional power grid power supply and demand control device 500 (see FIG. 2), and is hereinafter referred to as a generator output base command value.

  Furthermore, as shown in FIG. 1, the economic load redistribution device 300 includes an LPF 30, an economic load distribution correction amount calculation unit 31, and an economic load redistribution amount calculation unit 32.

  The LPF 30 is a low-pass filter that takes in part or all of the integration amount integrated by the integration amount calculation unit 8 as an input signal, removes a short period component from the signal, and outputs a signal with a long period component. Subsequently, the economic load distribution correction amount calculation unit 31 calculates an economic load distribution correction amount based on the output signal from the LPF 30. The economic load distribution correction amount may be the magnitude of the output signal from the LPF 30 itself.

Further, the economic load redistribution amount calculation unit 32 distributes the calculated economic load distribution correction amount to each generator 41 (#i) (i = 1,..., N). At this time, the distribution ratio by which the economic load redistribution amount calculation unit 32 distributes the economic load distribution correction amount to the generators 41 (#i) (i = 1,..., N) is the generator 41 in the equation (5). It is assumed that ( _i ) is given by b _i / (2 · a _i ) using fuel characteristic coefficients a _i and b _i of (#i).

  Next, the economic load redistribution apparatus 300 sets the economic load redistribution device to the generator output base command value calculated by the economic load distribution unit 24 for the generator 41 (#i) (i = 1,..., N). The economic load redistribution amount distributed to the generator 41 (#i) (i = 1,..., N) by the distribution amount calculation unit 32 is added, and the added amount is used as the EDC command value 33 (#i) (i = 1,..., N) and output toward the generator 41 (#i) (i = 1,..., N).

  As described above, the EDC command value 33 output from the economic load redistribution device 300 is the generator output base command value calculated by the economic load distribution control device 200 in consideration of the economy, and the load frequency control device 100. The long period component of the output amount from the integral amount calculation unit 8 by the LPF 30 is distributed and corrected by the distribution amount. That is, in the present embodiment, an amount proportional to the integral value of the regional requirement amount (AR) (the output amount of the integral amount calculation unit 8) is subtracted from the LFC control amount, and the reduced amount is an economic load. Redistribution is performed by the redistribution device 300 as an amount constituting a part of the EDC command value 33 (#i) (i = 1,..., N).

  This means that when a control residue occurs in the LFC control amount, the control residue is redistributed to the EDC, and the control in the intermediate period region of the control cycle by the EDC and the LFC is sufficiently performed. This means that the problem of the prior art is not solved or improved. Therefore, in the power system power supply and demand control apparatus 400 according to the present embodiment, it is possible to eliminate or reduce the residual control generated in the intermediate period region portion of the control cycle by EDC and LFC in the power supply and demand control in the power system 42. .

  When it is necessary to quickly reflect the corrected EDC command value 33 in the power system 42, the output cycle of the EDC command value 33 from the economic load redistribution device 300 is changed from the economic load distribution control device 200. What is necessary is just to make it shorter than the cycle (output cycle of the EDC command value 33 in the conventional sense) in which the generator output base command value is output. However, it is not necessary that the output cycle be equal to or shorter than the output cycle of the LFC command value 11 from the load frequency control device 100.

  Next, an example of the power supply / demand control operation in the power system power supply / demand control apparatus 400 according to the first embodiment of the present invention will be described with reference to FIGS. Here, FIG. 3 shows an example of a time chart that causes power supply / demand fluctuations in the power system 42 (a) when the generator output base command value is changed, and (b) an example of a time chart when the load amount fluctuates. FIG. FIG. 4 shows (a) AR, (b) proportional amount, (c) differential amount, (d) calculated in the power system power supply and demand control device when power supply and demand fluctuation occurs in the power system 42. FIG. 4 is a diagram showing an example of a time chart of integration amount. FIG. 5 is a time chart of (a) LFC control amount and (b) generator output command value calculated in the power system power supply and demand control device when power supply and demand fluctuation occurs in the power system 42. It is the figure which showed the example.

  As shown in FIG. 3A, when the generator output base command value for the generator 41 in the power system 42 is changed, or as shown in FIG. 3B, the load amount of the load 43 is large. When there is a fluctuation, an imbalance occurs in the power supply and demand in the power system 42. At this time, the power grid power supply and demand control device 400 outputs the LFC command value 11 and the EDC command value 33 to the generator 41 as described above, thereby eliminating the power supply and demand imbalance.

  Conventionally, since the EDC command value 33 is output in a long cycle (for example, several minutes to several tens of minutes), at least for several minutes to several tens of minutes, there is an imbalance in power supply and demand in the power system 42. Needs to be resolved only by controlling the LFC command value 11. On the other hand, in the case of the present embodiment, a long period component of a part of the LFC control amount (that is, the output amount of the integral amount calculation unit 8) is reflected in the EDC command value 33. Therefore, the power supply / demand imbalance in the power system 42 is quickly resolved by the cooperative control of the LFC and the EDC.

  As described above, the unbalanced amount of power supply and demand in the power system 42 is expressed as AR (regional demand amount). Therefore, when the output base command value of the generator 41 or the load amount in the electric power system 42 is changed (see FIGS. 3A and 3B), as shown in FIG. AR (regional demand) occurs.

  In this embodiment, the power supply / demand imbalance is eliminated by cooperative control by LFC and EDC, so AR (solid line in FIG. 4A) rapidly converges to zero and disappears. On the other hand, in the conventional case, cooperative control by LFC and EDC is not performed, and the power supply / demand imbalance is solved only by LFC, so that AR (broken line in FIG. 4A) is associated with PID control. As a result, the undershoot to the negative side cannot be fully resolved, and it takes time to converge to zero.

  Further, (b) proportional amount, (c) differential amount, and (d) integral amount in FIG. 4 are based on AR (region required amount) in FIG. This corresponds to the proportional amount, the differential amount, and the integral amount calculated by the calculation unit 7, the differential amount calculation unit 6, and the integral amount calculation unit 8. Also, the (a) LFC control amount in FIG. 5 corresponds to the LFC control amount calculated by the LFC control amount calculation unit 9. In either case, it can be seen that the convergence to zero is faster in the present embodiment (with cooperative control) than in the conventional case (without cooperative control).

  Further, (b) the generator output command value in FIG. 5 is, for example, the output command value to the generator 41 when the generator output base command value is changed as shown in FIG. It shows how it stabilizes following the generator output command value. From this, it can be seen that the stabilization time is shorter in the present embodiment (with cooperative control) than in the conventional case (without cooperative control).

(Modification of the embodiment)
The following can be understood from FIGS. 3A and 4A described above. That is, when the power demand in the power system 42 is balanced with the total output of each generator 41 at a certain point in time and the AR (regional requirement amount) is “zero”, the power system power supply / demand control apparatus 400 When a new EDC command value 33 is output to the generator 41 based on the power demand of the next control section of the EDC, the power supply / demand temporarily becomes unbalanced due to the output change of the generator 41 at that time. , AR (regional demand) occurs.

Therefore, in the modification of this embodiment, the total generated power EDC deviation amount calculated by the following equation (7) is input to the integral amount calculation unit 8.
The total power generated EDC deviation = Σ _{(P i} -BASE i) formula (7)
Here, _{P i} is power generation amount of the generator 41 (#i),
BASE _i indicates the generator 41 (#i) in the next control section of EDC control.
Generator output base command value,
Σ represents the total sum from i = 1 to n.

Therefore, the integration amount calculated by the integration amount calculation unit 8 is expressed by the following equation (4) ′.
Integration amount = Gi · Σ {AR (τ) + Σ (P _i (τ) −BASE _i )} Equation (4) ′
Here, the sigma outside {} represents the total sum from τ = 1 to t.

  In this case, the total generated power EDC deviation amount expressed by the equation (7) is controlled in advance by the LFC. Accordingly, when the EDC reaches the next control section, the power generation amount of the generator 41 at that time is close to the generator output base command value in the next control section of the EDC. As a result, the power supply / demand imbalance at the time when the EDC shifts to the next control section is minimized. Therefore, a large AR (regional requirement amount) as shown in FIG. 4A hardly occurs.

  In addition, the total generated power EDC deviation amount expressed by the equation (7) is not only controlled by the LFC, but also input to the economic load redistribution device 300 via the integral amount calculation unit 8. But it will be shared and controlled.

(Second Embodiment)
FIG. 6 is a diagram showing an example of the configuration of the power system power supply and demand control apparatus according to the second embodiment of the present invention. In the power system power supply and demand control apparatus 400 (see FIG. 1) according to the first embodiment, the output from the integral amount calculation unit 8 is input to the LPF 30, but the power system power supply and demand according to the second embodiment. In the control device 400a, the output from the LFC control amount calculation unit 9 is input to the LPF 30.

  Therefore, in the present embodiment, the differential amount calculated by the differential amount calculation unit 6 and the proportional amount calculated by the proportional amount calculation unit 7 are added to the LPF 30 to the integration amount calculated by the integral amount calculation unit 8. And input to the LPF 30. The differential amount is removed as a short cycle component by the LPF 30, and the proportional cycle also has a small long cycle component. Therefore, the output signal from the LPF 30 does not differ greatly between the case of the first embodiment and the case of the second embodiment.

  Except for the above points, the configuration and operation of the power system power supply and demand control apparatus 400a according to the second embodiment are the same as those of the power system power supply and demand control apparatus 400 according to the first embodiment. The description is omitted.

(Effect of embodiment)
Hereinafter, effects of the embodiment described above will be described together.
First, in the present embodiment, all or part of the long-period component of the control amount (LFC command value 11) to be borne by the LFC (load frequency control device 100) is the economic load redistribution device. Since 300 is added to the control amount (EDC command value 33) to be borne by the EDC (economic load distribution control device 200), the burden of the control amount by the LFC is reduced. That is, since the LFC command value 11 per LFC is reduced, the load frequency control device 100 increases the LFC command value 11 even when the supply and demand imbalance in the same positive or negative direction continues for a long time. Can continue to output for a period.

  Second, in this embodiment, since the burden of the control amount by the LFC is reduced, the controllability of the LFC can be achieved even in the case of the power system 42 in which the number of generators 41 to be subjected to LFC is small. And applicability is improved.

  Thirdly, in the present embodiment, the control amount turned from the LFC share to the EDC share is determined so that the total power generation fuel cost is reduced in accordance with the fuel consumption characteristics of the generator 41, The EDC command value 33 for the generator 41 is distributed. Therefore, it is possible to reduce the total power generation cost by eliminating the power supply / demand imbalance in cooperation with the LFC and the EDC as in the present embodiment rather than eliminating the imbalance in the power supply and demand.

  Fourthly, in the present embodiment, since the burden of the control amount by the LFC is reduced, it is possible to reduce the number of generators 41 that are the targets of the LFC. Accordingly, a decrease in power generation efficiency associated with the output adjustment of the generator 41 by LFC can be suppressed, so that the total power generation cost is reduced.

  Fifth, in the modified example of the present embodiment, not only the AR (regional requirement amount), but also the imbalance in the power supply and demand that occurs when the output of the generator 41 is changed in a long cycle by EDC, Since the EDC and the EDC perform the control in a coordinated manner, the imbalance between the supply and demand is not accumulated and is eliminated by the next EDC control stage.

  In the present embodiment, as a result of the above effects, the remaining power supply and demand control in the intermediate period region portion of the control cycle by LFC and EDC is eliminated or reduced, and the system frequency in the power system 42 is reduced while suppressing the total power generation cost. Is maintained at the reference frequency, and the quality of the power system can be improved.

DESCRIPTION OF SYMBOLS 1 System frequency 2 Reference frequency 3 Interconnection line power flow 5 Area requirement calculation part 6 Differential quantity calculation part 7 Proportional quantity calculation part 8 Integral quantity calculation part 9 LFC control quantity calculation part 10 Proportional distribution quantity calculation part 11 LFC command value 20 Power generation Machine output 21 Demand value 22 Demand forecast value 23 Economic load distribution control amount calculation unit 24 Economic load distribution unit 30 LPF
31 Economic load distribution correction amount calculation unit 32 Economic load redistribution amount calculation unit 33 EDC command value 40 Generator output control device 41 Generator 42 Power system 43 Load 44 Interconnection line 45 Other power system 100 Load frequency control device 200 Economic load Distribution control device 300 Economic load redistribution device 400, 400a Power system power supply / demand control device 500 (Conventional) power system power supply / demand control device

Claims (10)

A power system power supply and demand control device for controlling power supply and demand in a power system configured to include loads of a plurality of generators and a plurality of consumers,
For each first time period, obtain an unbalance amount of power demand in the power system, calculate a control amount of generated power for eliminating the unbalance amount, divide the calculated control amount, and A load frequency control device that distributes to the generators belonging to the power system, and outputs the allocated control amount as an LFC command value to the generator to be allocated;
For each second time period that is longer than the first time period, the total power generation cost of the generators belonging to the power system based on the preset predicted value of power demand in the power system and the current demand value Economic load distribution control device for calculating the generator output base command value of each generator,
For each third time period that is the same as the second time period or shorter than the second time period and longer than the first time period, from the load frequency control device, the load frequency control device Part or all of the control amount calculated in step (b) is obtained, an economic load distribution correction amount is calculated based on the acquired control amount, and the calculated economic load distribution correction amount is used as the power generation cost of each generator. In response to the generator load base command value of each generator calculated by the economic load distribution control device is corrected with the distributed economic load distribution correction amount, An economic load redistribution device for outputting the corrected generator output base command value of each generator as an EDC command value to the respective generator;
An electric power system power supply and demand control device comprising: 2. The power system power supply and demand control apparatus according to claim 1, wherein the control amount acquired by the economic load redistribution device from the load frequency control apparatus is an integral amount of the power supply and demand imbalance amount. The control amount acquired by the economic load redistribution device from the load frequency control device is a PID control amount including a differential amount, a proportional amount, and an integral amount of the unbalanced amount of the power supply and demand. The power grid power supply and demand control device according to 1. The economic load redistribution device
The power according to claim 1, wherein a low-pass filtering process is added to the control amount acquired from the load frequency control device, and the economic load distribution correction amount is calculated based on the control amount obtained by adding the low-pass filtering process. Grid power supply and demand control device. When the load frequency control device calculates the integral amount, the sum of the generator output base command values of the generators calculated by the economic load distribution control device is subtracted from the total power generation amount of the plurality of generators. The power grid power supply and demand control device according to claim 2 or 3, wherein an amount is added to the power imbalance amount, and the added amount is integrated. A power system power supply and demand control method by a power system power supply and demand control device for controlling power supply and demand in a power system configured to include loads of a plurality of generators and a plurality of consumers,
The power grid power supply and demand control device,
For each first time period, obtain an unbalance amount of power demand in the power system, calculate a control amount of generated power for eliminating the unbalance amount, divide the calculated control amount, and A load frequency control device that distributes to the generators belonging to the power system, and outputs the allocated control amount as an LFC command value to the generator to be allocated;
For each second time period that is longer than the first time period, the total power generation cost of the generators belonging to the power system based on the preset predicted value of power demand in the power system and the current demand value Economic load distribution control device for calculating the generator output base command value of each generator,
An economic load redistribution device that corrects each of the generator output base command values calculated by the economic load distribution control device based on a control amount obtained from the power grid power supply and demand control device;
With
The economic load redistribution device
For each third time period that is the same as the second time period or shorter than the second time period and longer than the first time period,
A first process of acquiring a part or all of a control amount calculated by the load frequency control device from the load frequency control device, and calculating an economic load distribution correction amount based on the acquired control amount;
A second process of allocating the calculated economic load distribution correction amount to the respective generators according to the power generation costs of the respective generators;
The generator output base command value of each generator calculated by the economic load distribution control device is corrected with the distributed economic load distribution correction amount, and the corrected generator output base command value of each generator is corrected. And a third process for outputting to the respective generators as EDC command values;
A power grid power supply and demand control method characterized in that The control amount acquired by the economic load redistribution device from the load frequency control device is an integral amount of the unbalanced amount of the power supply and demand. The control amount acquired by the economic load redistribution device from the load frequency control device is a PID control amount including a differential amount, a proportional amount, and an integral amount of the unbalanced amount of the power supply and demand. 6. The power grid power supply and demand control method according to 6. The economic load redistribution device adds a low pass filtering process to the control amount acquired from the load frequency control device in the first process, and calculates the economic load distribution correction amount based on the control amount obtained by adding the low pass filtering process. The power system power supply and demand control method according to claim 6, wherein the power system power supply and demand control method is calculated. When the load frequency control device calculates the integral amount, the sum of the generator output base command values of the generators calculated by the economic load distribution control device is subtracted from the total power generation amount of the plurality of generators. The power system power supply and demand control method according to claim 7 or 8, wherein an amount is added to the power imbalance amount, and the added amount is integrated.

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