JP5633963B2 - Control method for power system stabilizer - Google Patents

Description

  The present invention relates to a control method for a power system stabilizing device. More specifically, the present invention relates to a control method for a power system stabilizing device that is particularly suitable for application to a power system in which the frequency is constantly changing.

  As a conventional power system stabilizing device, for example, a reference frequency, a reference voltage, an active power amount, and a reactive power amount of a power supply system that connects a first facility that outputs power and a second facility that consumes power And a control means for controlling the amount of active power and reactive power output from the secondary battery system according to the detection result of the detection means (Patent Document) 1).

JP-A-2001-292531

  However, in the power system stabilizing device of Patent Document 1, the frequency deviation is deviated from the reference frequency on the assumption that the reference frequency is constant at the rated frequency 50/60 [Hz]. Therefore, for example, a power system in a small remote island cannot be applied to a system where the reference frequency cannot be regarded as a constant value at the rated frequency because the frequency fluctuates greatly every moment. There is. For this reason, it is difficult to say that it is widely applicable to power systems of various types and characteristics and is highly versatile.

  Therefore, an object of the present invention is to provide a control method for a power system stabilizing device that can stabilize a power system in consideration of a constant fluctuation of a variable power source and a constant fluctuation of a reference frequency.

  In order to achieve this object, a control method for a power system stabilization device according to claim 1 is a power system stabilization device in a power system in which a variable power source is connected and a power system stabilization device is introduced. And extracting a periodic component Δfa less than or equal to the first period from the fluctuation Δf of the system frequency of the power system and the second period (however, the first period of the output fluctuation ΔP of the active power of the variable power source) The periodic component ΔPb of the second cycle <the first cycle) or less is extracted, and the power system is stabilized using the sum of the cycle component Δfa less than the first cycle and the cycle component ΔPb less than the second cycle. A change in the output of the apparatus is derived, and the change in the output of the power system stabilization apparatus is used for controlling the output of the power system stabilization apparatus.

  Therefore, according to the control method of the power system stabilizer, the main power supply body to the power system is controlled because the output fluctuation ΔP of the active power of the variable power source is considered in the control of the power system stabilizer. For example, it is possible to appropriately cope with a periodic component of load fluctuation, which is considered to have a small frequency fluctuation suppression effect by an internal combustion power generator or a control method based on fluctuation Δf of the system frequency, and the system frequency of the power system Since the variation Δf is also taken into account, it is possible to appropriately cope with the remaining periodic components of the load variation.

  According to a second aspect of the present invention, in the control method for the power system stabilizing device according to the first aspect, the first period is any value in the range of 10 to 20 seconds. According to a third aspect of the present invention, in the control method for the power system stabilizing device according to the first aspect, the second period is any value within a range of 0.1 to 10 seconds. . In these cases, the first period and the second period are appropriately set.

  According to the control method of the power system stabilizing device of the present invention, in addition to the output fluctuation ΔP of the active power of the variable power source every moment after dividing the period to be considered in the control of the power system stabilizing device. Since the variation Δf of the grid frequency of the power system is also taken into account, the influence on the grid mainly on the grid frequency plane is appropriately suppressed without being affected by the periodic characteristics of the variation of the grid frequency of the power system. It is possible to improve the versatility of stabilizing the power system and improve the reliability.

It is a control block diagram (first half part) of the control method of the electric power system stabilization apparatus of this invention. It is a control block diagram (latter half part) of the control method of the electric power system stabilization apparatus of this invention. It is a figure which shows the outline | summary of the electric power grid | system to which this invention of Example 1 is applied.

  Hereinafter, the configuration of the present invention will be described in detail based on an example of an embodiment shown in the drawings.

  1 and 2 show an example of an embodiment of a control method for a power system stabilizing device of the present invention. The control method of the power system stabilization device is a control method of a power system stabilization device in a power system in which a variable power supply is connected and a power system stabilization device is introduced. The frequency component Δfa that is equal to or less than the first cycle is extracted from the frequency variation Δf and the output variation ΔP of the active power of the variable power source is equal to or less than the second cycle (where the second cycle <the first cycle). The periodic component ΔPb is extracted, and the change of the output of the power system stabilizing device is derived using the sum of the periodic component Δfa less than or equal to the first period and the periodic component ΔPb less than or equal to the second period. Changes in the output of the system stabilizer are used for controlling the output of the power system stabilizer.

  Here, the control method of the power system stabilizing device according to the present invention is mainly based on a system using a variable power source (also called a distributed power source or an intermittent power source) such as a wind power generation facility in a small-scale independent power system in an island region, for example. This is particularly effective when suppressing the influence of the frequency plane on the system. Specifically, for example, an electric power system with a maximum demand of about 1000 [kW], a non-intermittent power generator with a total power of about 1000 [kW], and a wind power generation facility with a total of about 500 [kW] In the situation where a flywheel of about 200 to 250 [kW] is introduced as a power system stabilization device and a variable power supply such as the above is connected, the flywheel reduces the influence of the variable power supply on the system frequency The present invention is particularly effective when used for controlling the active power of the flywheel in this case (note that all numerical values [kW] are rated outputs).

  A control block diagram showing the overall configuration of the control method of the power system stabilizing device of the present invention is shown in FIGS. Note that “s” in FIGS. 1 and 2 is a Laplace operator (differential operator).

  First, the frequency f of the power system is input to the reset circuit 29A, and the fluctuation Δf [PU] of the system frequency is output. The frequency f of the power system is measured, for example, by inputting the bus voltage of the power plant to the transducer.

  The reset circuit 29A is an element that does not output when the input is constant but outputs the change in input. For example, a large output is output for an input that changes abruptly like a step, while a small output is output for an input that changes slowly. That is, the filter operates in the same manner as a filter that does not pass vibration components having a long period.

  The variable Tf of the reset circuit 29A is a time constant, and is a constant for determining how long the vibration component is to reduce the output. The time constant Tf is set as appropriate based on the analysis of the system. Specifically, for example, the time constant Tf is set to about 10 [seconds] in consideration of whether only input elements having a certain period of the system frequency are reflected in the output. Is done.

  The fluctuation Δf [PU] of the system frequency output from the reset circuit 29A is input to the detection delay circuit 1.

  The detection delay circuit 1 outputs an output that gradually approaches an input value over a certain time with respect to an input that changes abruptly (specifically, a frequency deviation). Also called first-order lag element.

  The variable T1 of the detection delay circuit 1 is a time constant, and when there is a step-like change, the time from when the change occurs until it reaches 63.2% of the change is defined as the time constant. Specifically, for example, the time constant T1 is set to 0.01 [seconds] in consideration of the detection delay of various electrical quantities (that is, the time necessary for detection).

  The output from the detection delay circuit 1 is multiplied by a system constant C1 as frequency fluctuation sensitivity (reference numeral 2 in FIG. 1). The system constant C1 is a coefficient that represents how much the power consumption changes with respect to a certain frequency change from the viewpoint of static characteristics, and is represented by the reciprocal of the speed regulation rate of the governor (that is, the governor). Specifically, the system constant C1 is set to 120 in consideration of, for example, a speed regulation rate of 0.83%. The speed regulation rate is a constant that quantitatively indicates how much the output of the generator can be increased or decreased when the frequency changes from the reference value, and is a value that differs for each generator.

  The output from the detection delay circuit 1 multiplied by the system constant C 1 is input to the reset circuit 3.

  The reset circuit 3 is an element that outputs an input change rate. Specifically, when the input changes stepwise, the maximum value is 1 and the output is attenuated with a time constant T2, while when the input is a constant value, the output is zero. That is, it acts as a high-pass filter that does not pass vibration components having a long period.

  The variable T2 of the reset circuit 3 is a time constant, and is a constant for determining how long a vibration component should be prevented from passing. In the present invention, the time constant T2 is an important variable in that it determines the target range of suppression of the system frequency fluctuation Δf (hereinafter referred to as the first time constant T2). The first time constant T2 is appropriately set in consideration of system analysis and the like, and specifically, for example, is set to about 10 to 20 [seconds] in consideration of the vibration period to be controlled. Further, the first time constant T2 is set to a numerical value (that is, a numerical value having a long cycle) larger than the time constant T4 of the reset circuit 8 in the preprocessing for the output fluctuation ΔP of the active power of the variable power source described later.

  Here, the vibration cycle defined by the first time constant T2 is the first cycle, and the output from the reset circuit 3 is mainly the cycle component Δfa which is not more than the first cycle.

  An output Δfa from the reset circuit 3 is input to the limiter 4.

  The limiter 4 determines an upper limit and a lower limit of the control signal.

  The variable Ff of the limiter 4 is a constant for setting so as not to exceed the hardware limit, and is set in consideration of the rated capacity of the flywheel.

  The output from the limiter 4 is input to the unit conversion circuit 5 and converted from the PU unit system to the kW unit system.

  The variable B1 of the unit conversion circuit 5 is a base value used for unit conversion associated with the PU unit system. Specifically, for example, the base value B1 is set to 100 when converting from PU to%.

  By passing through the detection delay circuit 1 to the unit conversion circuit 5 in order, preprocessing is performed for the fluctuation Δf [PU] of the system frequency based on the frequency f of the power system every moment.

  On the other hand, for example, active power P, which is an output of a variable power source such as a wind power generation facility, is input to the reset circuit 29B, and an output fluctuation ΔP [PU] of the active power is output. Note that the effective power P of the variable power source is measured, for example, by inputting the terminal voltage and current of wind power generation to the transducer. The reset circuit 29B functions in the same manner as the above-described reset circuit 29A, and the variable Tp of the reset circuit 29B is the same as the time constant Tf of the reset circuit 29A.

  The output fluctuation ΔP [PU] of the active power output from the reset circuit 29B is input to the detection delay circuit 6.

  The detection delay circuit 6 outputs an output that gradually approaches an input value over a certain time with respect to an input that changes abruptly (specifically, output fluctuation of a variable power supply (distributed power supply, intermittent power supply)). To do. Also called first-order lag element.

  The variable T3 of the detection delay circuit 6 is a time constant, and when there is a step-like change, the time from when the change occurs until it reaches 63.2% of the change is defined as the time constant. Specifically, for example, the time constant T3 is set to 0.02 seconds in consideration of detection delay of various electrical quantities.

  The output from the detection delay circuit 6 is multiplied by a gain G as a degree to amplify the input signal (reference numeral 7 in FIG. 1). The gain G is a coefficient that specifies how many times the input signal is to be multiplied. Specifically, the gain G is set to 0.8 when, for example, it is desired to output 80% of the input signal.

  The output from the detection delay circuit 6 multiplied by the gain G is input to the reset circuit 8.

  The reset circuit 8 is an element that outputs an input change speed. Specifically, when the input changes stepwise, the maximum value is set to 1 and the output is attenuated with a time constant T4, while when the input is a constant value, the output is zero. That is, it acts as a high-pass filter that does not pass vibration components having a long period.

  The variable T4 of the reset circuit 8 is a time constant, and is a constant for determining how long a vibration component should be prevented from passing. In the present invention, this time constant T4 is an important variable in that it determines the target range of suppression of the output fluctuation ΔP of the active power that is the output of the variable power source (hereinafter referred to as the second time constant T4). ). The second time constant T4 is appropriately set in consideration of system analysis and the like, and specifically, for example, is set to about 0.1 to 10 [seconds] in consideration of the vibration period to be controlled. Then, the second time constant T4 is set to a numerical value smaller than the first time constant T2 of the reset circuit 3 in the preprocessing for the system frequency fluctuation Δf of the power system (that is, a numerical value having a short period). .

  Here, the vibration cycle defined by the second time constant T4 is the second cycle, and the output from the reset circuit 8 is mainly the cycle component ΔPb of the second cycle or less.

  An output ΔPb from the reset circuit 8 is input to the limiter 9.

  The limiter 9 determines an upper limit and a lower limit of the control signal.

  The variable Fp of the limiter 9 is a constant for setting so as not to exceed the hardware limit, and is set in consideration of the rated capacity of the flywheel.

  The output from the limiter 9 is input to the unit conversion circuit 10 and converted from the PU unit system to the kW unit system.

  The variable B2 of the unit conversion circuit 10 is a base value used for unit conversion associated with the PU unit system.

  By passing through the detection delay circuit 6 to the unit conversion circuit 10 in order, the pre-processing for the output fluctuation ΔP [PU] of the active power based on the active power P of the variable power source from moment to moment is performed.

  Then, the value [kW] based on the fluctuation Δf of the power system frequency output from the unit conversion circuit 5 that has been preprocessed and the variable power source that has been preprocessed and output from the unit conversion circuit 10. A value [kW] based on the output fluctuation ΔP of the active power is added (reference numeral 23 in FIG. 1). Further, outputs from a gain limiter 22 described later are added (reference numeral 24 in FIG. 2) and input to the limiter 11.

  The limiter 11 determines an upper limit and a lower limit of the control signal, and the upper limit and the lower limit can be arbitrarily changed and set by an external signal. The upper limit is set by an output from an upper limit setting circuit 18 described later, and the lower limit is set by an output from a lower limit setting circuit 20 described later.

  The output from the limiter 11 is input to the unit conversion circuit 12, and conversion from the kW unit system to the PU unit system is performed.

  The variable B3 of the unit conversion circuit 12 is a base value used for unit conversion associated with the PU unit system. Specifically, the base value B3 is 1/240 when 1 [PU] = 240 [kW], for example.

  The output from the unit conversion circuit 12 is multiplied by “−1” as code conversion (reference numeral 13 in FIG. 2). Then, the signal obtained by multiplying “−1” and converting the positive / negative as the input signal is input to the control delay circuit 14.

  The control delay circuit 14 outputs an output that gradually approaches an input value over a certain time with respect to an input that changes abruptly. Also called first-order lag element.

  The variable T5 of the control delay circuit 14 is a time constant, and when there is a step-like change, the time from when the change occurs until it reaches 63.2% of the change is defined as the time constant. Specifically, for example, the time constant T5 is set to 0.02 [seconds] in consideration of the control delay of the inverter control system.

The output from the control delay circuit 14 is multiplied by ω ₀ / ω (reference numeral 15 in FIG. 2). ω ₀ / ω is a coefficient for calculating the flywheel control torque from the flywheel control output, ω ₀ is the rated angular velocity of the flywheel, and ω is the momentary angular velocity of the flywheel.

A change in the rotational speed of the flywheel (in other words, a change in the output of the flywheel as a power system stabilizing device) is derived from the change in the control torque of the flywheel calculated by multiplying ω ₀ / ω (FIG. 2). Medium code 16). Here, M is a unit inertia constant of the flywheel, and s is a Laplace operator.

Then, the change in the rotational speed of the flywheel derived by the above processing is subtracted from the rated rotational speed ω _REF [PU] of the flywheel (reference numeral 25 in FIG. 2), and the flywheel rotational speed (hereinafter referred to as FW rotation). Ω _t [PU] is calculated.

The FW rotation speed ω _t [PU] is sent to a flywheel control system (not shown) as a power system stabilization device and used for flywheel control.

The FW rotation speed ω _t [PU] is also used for setting an upper limit and a lower limit of a flywheel control output (hereinafter referred to as FW control output).

First, in order to set the upper limit of the FW control output, the FW rotation speed ω _t [PU] is converted from the PU unit system to the rpm unit system by the unit conversion circuit 17 (after conversion: ω _r ), and the flywheel specifications A difference (that is, Rmax−ω _r [rpm]) from the upper maximum rotational speed Rmax [rpm] is calculated (reference numeral 26 in FIG. 2).

The difference (= Rmax−ω _r [rpm]) is input to the upper limit setting circuit 18, and the upper limit setting circuit 18 sets the upper limit of the FW control output. The upper limit setting circuit 18 determines the upper limit of the FW control output based on the difference between the current rotational speed of the flywheel and the maximum rotational speed Rmax. Specifically, the rotational speed of the flywheel reaches the maximum rotational speed Rmax. Then, the upper limit of the FW control output is set to zero so that the output of the flywheel is controlled so as not to increase further.

  A coefficient 10000 of the upper limit setting circuit 18 is a gain coefficient for setting the upper limit of the FW control output to 0 so that the output of the flywheel is not increased any more when the rotational speed of the flywheel reaches the maximum rotational speed Rmax. The gain coefficient is such that the FW control output is set to a predetermined value (for example, a variable F1 [kW] described later) until the FW rotation speed reaches the maximum rotation speed Rmax, and the FW control output is output immediately before reaching the maximum rotation speed Rmax. It is set to be changed to 0 [kW], and is set to 10000 in this embodiment. The gain coefficient is not limited to 10000.

  The variable F1 of the upper limit setting circuit 18 is the upper limit (unit [kW]) of the output of the flywheel, and is set in consideration of the specifications of the flywheel.

On the other hand, in order to set the lower limit of the FW control output, the FW rotation speed ω _t [PU] is converted from the PU unit system to the rpm unit system by the unit conversion circuit 19 (after conversion: ω _r ), and the flywheel specifications A difference (that is, Rmin−ω _r [rpm]) from the lowest minimum rotational speed Rmin [rpm] is calculated (reference numeral 27 in FIG. 2).

Then, the difference (= Rmin−ω _r [rpm]) is input to the lower limit setting circuit 20, and the lower limit setting circuit 20 sets the lower limit of the FW control output. The lower limit setting circuit 20 determines the lower limit of the FW control output based on the difference between the current rotational speed of the flywheel and the minimum rotational speed Rmin. Specifically, the rotational speed of the flywheel reaches the minimum rotational speed Rmin. Then, the lower limit of the FW control output is set to zero and the flywheel output is controlled so as not to further decrease.

  The coefficient 10000 of the lower limit setting circuit 20 is a gain coefficient for setting the lower limit of the FW control output to 0 so that the output of the flywheel is not further lowered when the rotational speed of the flywheel reaches the minimum rotational speed Rmin. The gain coefficient is such that the FW control output is set to a predetermined value (for example, -F1 [kW]) until the FW rotation speed reaches the minimum rotation speed Rmin, and the FW control output is set to 0 [ kW], and is set to 10000 in this embodiment. The gain coefficient is not limited to 10000.

  The variable F1 of the lower limit setting circuit 20 is the same as the variable F1 of the upper limit setting circuit 18.

  The upper limit value of the FW control output set by the upper limit setting circuit 18 and the lower limit value of the FW control output set by the lower limit setting circuit 20 are input to the limiter 11, and the upper limit value and lower limit value of the limiter 11 are input. Used as

Further, using the FW rotation speed ω _r converted into the rpm unit system by the unit conversion circuit 19, a difference from the center rotation speed Rmid [rpm] in the flywheel specifications (that is, Rmid−ω _r [rpm]) Is calculated (reference numeral 28 in FIG. 2). Then, the difference (= Rmid−ω _r [rpm]) is input to the control delay circuit 21.

  The control delay circuit 21 is one of functions for returning the rotational speed of the flywheel to the central rotational speed Rmid when the rotational speed deviates from the central rotational speed Rmid. This is an output that gradually approaches the input value over a certain time with respect to the deviation from the center rotational speed Rmid). Also called first-order lag element. The control delay circuit 21 acts as a low-pass filter that does not allow a vibration component having a short vibration period to pass through for a periodic input.

  The variable T6 of the control delay circuit 21 is a time constant, and is a constant for determining how short a vibration component should be prevented from passing. The time constant T6 is appropriately set based on system analysis and the like. Specifically, for example, it is set to about 5 [seconds] in consideration of not affecting the main output fluctuation cycle of the variable power supply (distributed power supply) and preventing the exhaustion of flywheel energy. Is done.

  The output from the control delay circuit 21 is input to the gain limiter 22.

The gain limiter 22 is one of functions for returning the rotational speed of the flywheel to the central rotational speed Rmid when the rotational speed of the flywheel deviates from the central rotational speed Rmid. , Rmid−ω _r [rpm]), an input signal in which a control delay by the control delay circuit 21 is added is amplified to determine an upper limit and a lower limit of the output control signal.

  The coefficient 0.1 of the gain limiter 22 serves to determine the force to be pulled back to the center rotational speed Rmid, that is, how fast the center rotational speed Rmid is when the flywheel rotational speed deviates from the central rotational speed Rmid. It acts to determine whether to return to. Note that the coefficient of the gain limiter 22 is not limited to 0.1, and is appropriately set in consideration of how quickly the gain should be returned to the center rotational speed Rmid.

  The variable F2 of the gain limiter 22 determines an upper limit and a lower limit of the force to be pulled back to the center rotational speed Rmid. Specifically, for example, the variable F2 is set to about 15 after considering the magnitude and frequency of the rotational speed of the flywheel that deviates from the central rotational speed Rmid.

  Then, the output from the limiter 22 with gain is added to the sum of the output from the unit conversion circuit 5 and the output from the unit conversion circuit 10 (reference numeral 23 in FIG. 1) (reference numeral in FIG. 2). 24) Input to the limiter 11.

  According to the control method of the power system stabilizing device of the present invention configured as described above, it is possible to directly suppress the short period component of the output fluctuation of the variable power source such as the wind power generation facility at the ΔP portion. In addition, it is possible to suppress the relatively long frequency fluctuation component that cannot be suppressed by the internal combustion power generator in the Δf portion, and in addition, by making the flywheel center rotational speed control response faster, It is also possible to avoid charge / discharge energy depletion (that is, the rotation speed reaches the upper and lower limits) as much as possible. In particular, by increasing the responsiveness of this center speed control, it is possible to avoid the risk of frequency fluctuations that occur when the charge and discharge energy of the flywheel is exhausted, and when significant frequency fluctuations occur intermittently in a short time However, according to the control method of the power system stabilizing device of the present invention, it is possible to keep the power system stable.

  In addition, according to the control method of the power system stabilizing device of the present invention, the frequency fluctuation component Δf is used for stabilizing the power system, so even when an abnormality occurs in the power system due to some circumstances or accidents. It is possible to keep the power system stable. Specifically, for example, even when the internal combustion power generator has stopped or when there is a demand fluctuation in a large-scale consumer, according to the control method of the power system stabilizing device of the present invention, the stability of the power system is maintained. Is possible. That is, since the frequency fluctuation component Δf is in the entire system, even if the output (P) of only the variable power source such as a wind power generation facility is measured, the entire system including the internal combustion power generator This state can be detected as a fluctuation in the grid frequency, and for example, it is possible to stabilize the power system in consideration of a situation in which monitoring is not directly performed, such as a demand fluctuation in a large-scale customer.

  Furthermore, according to the control method of the power system stabilizing device of the present invention, the fluctuation Δf of the system frequency of the power system is taken into consideration (specifically, mainly from reference numerals 29A to 5 in FIG. 1). In addition, the process of reference numeral 23 is not a deviation from the reference frequency), and the output fluctuation ΔP of the active power of the variable power supply is taken into account (also from reference numeral 29B to reference numeral 10 and reference numeral 23). Therefore, it can be applied to a system in which the reference frequency cannot be regarded as a constant value at the rated frequency because the system frequency varies greatly from moment to moment, and is highly versatile.

  In addition, although the above-mentioned form is an example of the suitable form of this invention, it is not limited to this, A various deformation | transformation implementation is possible in the range which does not deviate from the summary of this invention. For example, in this embodiment, the power system stabilization device is configured to control the flywheel using a flywheel, but the power system stabilization device to which the present invention can be applied is limited to the flywheel. Instead, any other power storage device such as a battery, a superconducting power storage device (SMES), or a capacitor may be used as long as it can adjust the output of active power according to predetermined control.

  Further, as a variable power source (distributed power source, intermittent power source) linked to a power system to be stabilized by the present invention, specifically, for example, a wind power generator or solar power generation can be considered.

  The simulation result performed in order to verify the suppression effect of the system frequency fluctuation | variation by a flywheel by applying the control method of the electric power system stabilization apparatus of this invention is demonstrated using FIG.

  In this embodiment, the small-scale independent power system 30 shown in FIG. Specifically, the power system 30 has a maximum demand of about 800 [kW] combined with the load 34, and four diesel generators 31A, 31B, 31C, and 31D (rated outputs are 150, 150, 300, and 300, respectively). [kW]) and two wind power generators 32A and 32B (both rated outputs are 245 [kW]), and flywheel 33 (indicated as FW in FIG. 3) as a system stabilizing device; The rated output is 200 [kW]). In addition, since the frequency fluctuation (specifically, the fluctuation width of the maximum and minimum values of the frequency fluctuation) is usually about ± 0.30 [Hz], the management target value is also used in this embodiment. ] Is the management target value.

  In this embodiment, the first time constant T2 of the reset circuit 3 that defines the first cycle is set to 10 [seconds], and the second time constant T4 of the reset circuit 8 that defines the second cycle is used. Was 5 [seconds].

  A simulation was performed using time series data actually measured in the power system 30. As the time series data of actual measurement, the maximum value of wind power generation output is 159 [kW] in daily data, the peak of wind power generation output fluctuation is large, and the output fluctuation continues constantly. The one for the day was selected.

  In addition, in this embodiment, in order to examine the effect of wind power generation fluctuations on the grid frequency by simulation, the pitch angle control of the windmill is slow, the output of 159 [kW] appears, and the wind power with a fairly short period of less than 10 seconds appears. An actual measurement result in which a fluctuation in the power generation output was observed was picked up as an analysis target (for one wind power generator 32A). Furthermore, the simulation was performed by simulating a state in which the wind turbine introduction ratio was increased to about 50% by multiplying this measured time series data by 2.75 times.

  In the simulation, measured data for 5 minutes from the start of the high speed generator of the wind power generator 32A to the stop was used as time series data. Since the start / stop of the wind power generator 32A is included in the time-series data, it was possible to study the characteristics of the three phenomena of cut-in, constant output fluctuation, and cut-out with a single time-series data. .

  Using time series data of wind power generator output (that is, time series data obtained by multiplying actual measurement data by 2.75), a simulation was performed regarding fluctuations in system frequency in the absence of a system stabilization device. From the results of the simulation, the frequency fluctuation (specifically, the single fluctuation width of the maximum and minimum values of the frequency fluctuation) is ± 0.39 [Hz], and it vibrates about 0.40 [Hz] in the vertical direction from the rated frequency. I understood. And it was confirmed that this value is larger than the management target value 0.3 [Hz].

  Furthermore, the simulation on fluctuation of the system frequency when the present invention was applied was performed using the same time series data of the wind power generator output as described above (that is, time series data obtained by multiplying the actual measurement data by 2.75). From the result of the simulation, the frequency fluctuation (specifically, the single fluctuation width of the maximum and minimum values of the frequency fluctuation) was ± 0.12 [Hz]. This value was confirmed to be sufficiently smaller than the management target value 0.3 [Hz].

  From these results, according to the control method of the power system stabilizing device of the present invention, the output of the variable power supply that is a small-scale independent power system and that is a power system that is greatly affected by the variable power supply and that is connected. It was confirmed that even in an electric power system in which fluctuations continue constantly, fluctuations in the electric power system frequency can be reduced and the electric power system can be sufficiently stabilized.

Δf Periodic component ΔP less than or equal to the first period of the fluctuation Δfa Δf of the power system of the electric power system Periodic component less than or equal to the second period of the output fluctuation ΔPb ΔP of the active power of the variable power source

Claims (3)

  A control method for the power system stabilizing device in a power system in which a variable power source is connected and a power system stabilizing device is introduced, the first of the system frequency fluctuations Δf of the power system Extracting a period component Δfa less than or equal to a period and extracting a period component ΔPb less than or equal to a second period (where the second period is less than the first period) from the output fluctuation ΔP of the active power of the variable power source, A change in the output of the power system stabilizing device is derived using a sum of the period component Δfa less than or equal to the first period and the period component ΔPb less than or equal to the second period, A control method for a power system stabilizing device, wherein a change in output is used for controlling the output of the power system stabilizing device.   The method of controlling a power system stabilizing apparatus according to claim 1, wherein the first period is any value in a range of 10 to 20 seconds.   The method of controlling a power system stabilizing apparatus according to claim 1, wherein the second period is any value within a range of 0.1 to 10 seconds.

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