JP5946983B1 - Supply and demand control device, supply and demand control method - Google Patents

Abstract

Load frequency control is performed so that the demand and supply of power between the load and the load are balanced, and a plurality of first power generation devices that supply power to the load, and power is supplied to the load using renewable energy In a power system to which a second power generation device and a storage battery that charges the generated power of the second power generation device are connected, a supply and demand control device that controls parallel and disconnection of the plurality of first power generation devices, Each rated output value of the first power generator parallel to the power grid among the plurality of first power generators and power to the load until the first power generator parallel to the power grid is activated A first determination unit that determines whether or not a first addition value of the storage battery that continuously supplies the output value is insufficient with respect to the total demand of the load, and the first addition value is the Lack of total load demand That case, and a first control unit for parallel a predetermined first power generator which is Kairetsu from said electric power system among the plurality of first power generator.

Description

  The present invention relates to a supply and demand control device and a supply and demand control method.

  For example, as an electric power system provided on a remote island, an electric power system to which an internal combustion power generation device (first power generation device), a renewable energy power generation device (second power generation device), a storage battery, and a load are connected is known (for example, Patent Documents). 1).

  Renewable energy power generators have a structure that generates power using natural energy such as wind power and solar power, so the power generation output of renewable energy power generators is difficult to predict and depends on the weather conditions. It is unstable. Therefore, when introducing a renewable energy power generation device, (A) even if the power generation output of the renewable energy power generation device becomes zero, it is possible to supplement the supply of power to the load with the generated power of the internal combustion power generation device. B) The introduction amount of the renewable energy power generation apparatus is determined so as to satisfy the two conditions that the generated power of the renewable energy power generation apparatus does not become excessive. Here, when a plurality of internal combustion power generation devices are installed, if the same internal combustion power generation device is installed, the condition (A) is “maximum output of internal combustion power generation device × number of internal combustion power generation devices> load The condition (B) is expressed as “the minimum output of the internal combustion power generation apparatus × the number of internal combustion power generation apparatuses + the power generation output of the renewable energy power generation apparatus <the total load demand”.

  However, from the viewpoint of protecting the global environment, it is desirable to expand the introduction of renewable energy power generation devices. Therefore, as a result of introducing the renewable energy power generation device, if the generated power of the renewable energy power generation device does not satisfy the conditions (A) and (B) and surplus, the surplus power is charged using a storage battery, The charging power of the storage battery is discharged to the load in accordance with the power supply and demand plan. In this way, the introduction of renewable energy power generation devices has been expanded in the above power system.

JP 2011-114945 A

  However, since it is difficult to accurately predict the power generation output of the renewable energy power generation device, the following problems occur. For example, a case is assumed in which the power generation output of the renewable energy power generation device in the corresponding area on the corresponding day is predicted to be low based on weather-related data transmitted from the Japan Meteorological Agency, and the storage battery charging capacity is set to be small. In this case, even if the above prediction is not met and the power generation output of the renewable energy power generation device is increased and surplus power is generated, the storage battery cannot charge all the surplus power, and the power generation is excessive due to a shortage of reduction. There is a risk of becoming.

  Therefore, the present invention provides a supply and demand control device that controls parallel and disconnection of the first power generator with respect to the power system so that the amount of power supplied to the load can be secured even when the power generation output of the second power generator fluctuates. An object is to provide a supply and demand control method.

  The main present invention for solving the above-mentioned problems is that a load frequency control is performed so that the demand and supply of power between the load and the load are balanced, and a plurality of first power generators that supply power to the load can be regenerated. In a power system to which a second power generation device that supplies power to the load using energy and a storage battery that charges the generated power of the second power generation device are connected, the plurality of first power generation devices are connected in parallel and A supply and demand control device for controlling a row, wherein each rated output value of a first power generation device that is parallel to the power system among the plurality of first power generation devices and the first power supply that is parallel to the power system. A first determination is made as to whether or not the first added value of the output value of the storage battery that continuously supplies power to the load until the power generation device is activated is insufficient with respect to the total demand of the load. A determination unit and the first processor A first control unit configured to parallel a predetermined first power generation device disconnected from the power system among the plurality of first power generation devices when a value is insufficient with respect to the total demand of the load; I have.

  Other features of the present invention will become apparent from the accompanying drawings and the description of this specification.

  ADVANTAGE OF THE INVENTION According to this invention, even when the electric power generation output of a 2nd electric power generating apparatus fluctuates, it becomes possible to control the parallel and disconnection of a 1st electric power generating apparatus with respect to an electric power grid | system so that the supply amount of the electric power with respect to a load can be ensured. Become.

It is a figure which shows an example of the electric power grid | system controlled by the supply-and-demand control apparatus which concerns on this embodiment. It is a figure which shows the input / output with respect to the supply-and-demand control apparatus which concerns on this embodiment. It is a figure which shows the structure of the supply-and-demand control apparatus which concerns on this embodiment. It is a flowchart which shows the whole control operation | movement of the supply-and-demand control apparatus which concerns on this embodiment. It is a flowchart which shows the normal supply-and-demand control operation of the supply-and-demand control apparatus which concerns on this embodiment. It is a flowchart which shows the supply-and-demand control operation | movement of the supply-and-demand control apparatus which concerns on this embodiment when the internal combustion power generator is the minimum number or the number of units which cannot be disconnected, and the power generation output of an internal combustion power generator falls below the minimum output. It is a figure which shows the characteristic of the supply-and-demand control apparatus which concerns on this embodiment when the power generation output of an internal combustion power generation device falls below the minimum output with the minimum number of internal combustion power generation devices or the number which cannot be disconnected. It is a figure which shows the characteristic of the supply-and-demand control apparatus which concerns on this embodiment when the power generation output of an internal combustion power generation device falls below the minimum output with the minimum number of internal combustion power generation devices or the number which cannot be disconnected. It is a flowchart which shows the other supply-and-demand control operation | movement of the supply-and-demand control apparatus which concerns on this embodiment, when the internal combustion power generator is the minimum number or the number which cannot be disconnected and the power generation output of an internal combustion power generator is less than the minimum output. It is a figure which shows the other characteristic of the supply-and-demand control apparatus which concerns on this embodiment, when the internal combustion power generator is the minimum number or the number which cannot be disconnected, and the power generation output of an internal combustion power generator is less than the minimum output.

At least the following matters will become apparent from the description of this specification and the accompanying drawings.
=== Power system ===
Hereinafter, with reference to FIG. 1 thru | or FIG. 3, the electric power system controlled by the supply-and-demand control apparatus which concerns on this embodiment is demonstrated. The power system in FIG. 1 is provided in a remote area such as a remote island.

  The electric power system 1 includes a plurality of internal combustion power generation devices 2 (2-1 to 2-n), a plurality of renewable energy power generation devices 3 (3-1 to 3-n), a storage battery 4, and a plurality of loads 5 (5- 1 to 5-n) are connected to the power line 6.

  The internal combustion power generation device 2 is a device that performs thermal power generation by rotating the internal combustion engine with chemical energy released by the combustion of fuel, and is configured using a compression ignition engine using a diesel engine, for example. Since the internal combustion power generator 2 has a feature that it can be started in a relatively short time, it is installed in a small-scale thermal power plant on a remote island and is operated efficiently. The internal combustion power generator 2 is composed of n devices having the same rated output, and is selectively paralleled or disconnected from the power line 6 in accordance with a control command from a supply and demand controller 7 described later. . The parallel internal combustion power generators 2 are started or stopped in accordance with a control command from the supply and demand controller 7, and load frequency control (LFC: LFC) is performed so that the power demand and supply with the load 5 are balanced. Load Frequency Control). In the following description, the internal combustion power generator 2 may be referred to as DG.

  The renewable energy power generation device 3 is a device that generates power using natural energy such as sunlight, wind power, wave power, tidal power, geothermal heat, and biomass. Here, the plurality of renewable energy power generation devices 3 may be power generation devices that use the same natural energy, or may be power generation devices that use different natural energy.

  The storage battery 4 is composed of, for example, a sodium / sulfur battery (NAS battery: registered trademark), and has a capacity capable of charging surplus power of the renewable energy power generation device 3. Sodium-sulfur batteries are rechargeable batteries that use sodium (Na) as the negative electrode, sulfur (S) as the positive electrode, and β-alumina solid electrolyte as the electrolyte that separates both electrodes, and are repeatedly charged and discharged by a chemical reaction of sulfur and sodium ions. is there. The storage battery 4 charges the surplus power of the renewable energy power generation device 3 according to a control command from the supply / demand control device 7 or discharges the charged power to the load 5 in accordance with the supply / demand plan of the power system 1.

  The load 5 is a power device that consumes power in a consumer such as a private house, a public facility, or a factory. Power is supplied to the load 5 from any one of the internal combustion power generation device 2, the renewable energy power generation device 3, and the storage battery 4 depending on the situation.

  The supply and demand control device 7 controls parallel and disconnection of the internal combustion power generation device 2 with respect to the power line 6, start and stop of the internal combustion power generation device 2, charge / discharge of the storage battery 4, and power flow of the power system 1. The supply and demand control device 7 is provided together with the internal combustion power generation device 2 in, for example, a small-scale thermal power plant.

  In order to perform the above-described control, the supply and demand control device 7 includes the number N of internal combustion power generation devices 2 in parallel, the power generation output DG of the internal combustion power generation device 2, the power generation output RE of the renewable energy power generation device 3, and the output S of the storage battery 4. Information indicating the charge level SOC of the storage battery 4, the total demand L of the load 5, and the frequency F of the power system 1 is input (positive during charging and negative during discharging). When the above information is input, the supply and demand control device 7 receives parallel and disconnection commands C for the internal combustion power generation device 2, start and stop commands D for the internal combustion power generation device 2, and charge / discharge commands E for the storage battery 4. Is output.

  The supply and demand control device 7 includes an input unit 7A, a storage unit 7B, a control unit 7C, and an output unit 7D. The input unit 7A includes the parallel number N of the internal combustion power generation devices 2 and the power generation output DG, the power generation output RE of the renewable energy power generation device 3, the output S and the charge level SOC of the storage battery 4, the total demand L of the load 5, the power system Information indicating the frequency F of 1 is input. The storage unit 7B stores program data for generating the commands C to E from the above information, table data necessary for generating the commands C to E, and the like. Based on the program data and table data read from the storage unit 7B, the control unit 7C calculates the above information obtained from the input unit 7A to generate commands C to E. The output unit 7D outputs commands C to E obtained from the control unit 7C. The commands C to E are transmitted from, for example, a small-scale thermal power plant via a communication line when controlling the internal combustion power generation device 2 and the storage battery 4.

  Here, the supply and demand balance of the electric power system 1 including the storage battery 4 will be described.

  The total demand L of the load 5 at time t is expressed by equation (1).

  Further, the supply and demand imbalance amount AR of the power system 1 is expressed by Expression (2).

(However, −K represents a constant, and ΔF represents a frequency deviation of the power system 1 at time t.)
Moreover, the receiving balance is satisfied by setting the output S of the storage battery 4 at time t + 1 to a value represented by the expression (3).

Then, by substituting Equation (2) into Equation (1), the total power generation output of the internal combustion power generation device 2, the total power generation output of the renewable energy power generation device 3, the total demand of the load 5, the supply / demand imbalance amount, the storage battery The load L is obtained from the output S of 4. That is, in Expression (3), the output _{St + 1} of the storage battery 4 can be said to be a value at a time t + 1 after the so-called time t, which is determined from the result of the value on the right side at the time t.
=== Operation of Supply / Demand Control Device ===
<< Overall control action >>
With reference to FIG. 4, the overall control operation of the supply and demand controller 7 will be described. The main body that controls the operation of FIG. 4 is the control unit 7C.

First, even if the total generated power of the internal combustion power generation device 2 and the renewable energy power generation device 3 exceeds the total demand of the load 5, the power generation output of the internal combustion power generation device 2 performing the load frequency control has the minimum target value. It is desirable that the storage battery 4 be in a discharged state as much as possible so that control is performed so as not to fall below. Therefore, the supply and demand control device 7 determines that the internal combustion power generation device has a state where the charge level SOC of the storage battery 4 is equal to or higher than the first charge level T ₁ in a state where the power generation output of the internal combustion power generation device 2 has not decreased to the minimum target value. Control is performed to discharge the storage battery 4 while performing load frequency control using at least one of the storage battery 2 and the storage battery 4. On the other hand, which internal combustion power generation device 2 among the plurality of internal combustion power generation devices 2 is parallel to or disconnected from the power system 1 at which timing depends on the power generation output of the renewable energy power generation device 3 on the corresponding day. And a predicted value of the demand of the load 5 are obtained from a predetermined calculation formula. For example, according to the calculation result, when any one of the internal combustion power generation devices 2 is expected to be started in a short time in parallel with the power system 1 at any time, from the viewpoint of economy such as fuel consumption, It is desirable to supply electric power from the storage battery 4 to the load 5 without paralleling the internal combustion power generator 2 to the power system 1. Therefore, the supply and demand control device 7 sets the charge level SOC of the storage battery 4 to the second charge level T ₁ + α (> first charge level T ₁₎ in a state where the power generation output of the internal combustion power generation device 2 has not decreased to the minimum target value. In the case of the above, control is performed to discharge the storage battery 4 while performing load frequency control using at least one of the internal combustion power generation device 2 and the storage battery 4 (S101). Details of step S101 will be described later.

  Next, the supply and demand control device 7 controls parallel and disconnection of the internal combustion power generation device 2 in accordance with fluctuations in the power generation output of the renewable energy power generation device 3, and the internal combustion power generation devices 2 that are already in parallel. Is also controlled (S102).

  The supply and demand control device 7, for example, as a result of a decrease in the power generation output of the renewable energy power generation device 3, the power generation output (rated output) of the internal combustion power generation device 2 that is currently operating and the power generation output of the renewable energy power generation device 3 When the supply amount of power to the load 5 is insufficient, the internal combustion power of any of the internal combustion power generation devices 2 that are disconnected so that the shortage of supply amount of power to the load 5 is resolved. The power generator 2 is started in parallel with the power system 1. On the other hand, the supply and demand control device 7, for example, as a result of an increase in the power generation output of the renewable energy power generation device 3, the power generation output (minimum output) of the internal combustion power generation device 2 that is currently operating and the When combined with the power generation output, if the supply amount of power to the load 5 becomes surplus, any one of the internal combustion power generation devices 2 in parallel so that the power generation output of the renewable energy power generation device 3 is not surplus The internal combustion power generator 2 is disconnected from the power system 1. In general, the internal combustion power generation device 2 is a thermal power generation device that burns fuel. Therefore, if the internal combustion power generation device 2 is frequently started and stopped, the fuel consumption is deteriorated. Therefore, the supply and demand control device 7 controls the number of parallel internal combustion power generation devices 2 with respect to the power system 1 in accordance with fluctuations in the power generation output of the renewable energy power generation device 3. Therefore, since the internal combustion power generation device 2 is not always in parallel with the power system 1, even if the power generation output of the renewable energy power generation device 3 fluctuates, the internal combustion power generation device 2 stops immediately after starting or immediately after stopping. The start-up is not performed frequently, and an economic merit can be obtained. Details of step S102 will be described later.

  Next, the supply and demand control device 7 determines whether or not the number of the internal combustion power generation devices 2 arranged in parallel with the power system 1 is either a predetermined minimum number or a number that cannot be disconnected (S103). ). Note that the number of internal combustion power generation devices 2 that cannot be disconnected means the number of internal combustion power generation devices 2 that are parallel to the power system 1 when the supply and demand control device 7 determines in step S102 that it cannot be disconnected. That is. Specifically, the number of internal combustion power generators 2 that cannot be disconnected means the minimum number that can supply power to the load 5 without a shortage when the power generation output of the renewable energy power generator 3 becomes zero. is there. When the number of the internal combustion power generators 2 that are arranged in parallel with the power system 1 is neither the predetermined minimum number nor the number that cannot be disconnected (S103: NO), the supply and demand controller 7 repeats the operation from step S101. .

  Next, when the number of internal combustion power generators 2 in parallel with the power system 1 is one of a predetermined minimum number or a number that cannot be disconnected (S103: YES), the supply and demand control device 7 It is determined whether or not the output value of the generated power of the internal combustion power generator 2 parallel to the system 1 has reached the minimum target value (S104). The minimum target value of the internal combustion power generator 2 is the minimum output value at which the internal combustion power generator 2 can supply power to the load 5. When the output value of the generated power of the internal combustion power generator 2 in parallel with the power system 1 has not reached the minimum target value (S104: NO), the supply and demand controller 7 repeats the operation from step S101.

  On the other hand, the number of internal combustion power generation devices 2 that are parallel to the power system 1 is either a predetermined minimum number or the number that cannot be disconnected, and the internal combustion power generation that is parallel to the power system 1. When the output value of the generated power of the device 2 reaches the minimum target value (S104: YES), the supply and demand control device 7 stores the storage battery so that the output value of the generated power of the internal combustion power generation device 2 does not fall below the minimum target value. 4 is controlled to charge the power generation output of the renewable energy power generation device 3 (S105). Details of step S105 will be described later.

  The overall control operation of the supply and demand control device 7 is an operation of repeating the above steps S101 to S105.

<< Supply and demand control action >>
With reference to FIG. 5, the details of step S <b> 101 in FIG. 4 at the time when the output value of the generated power of the internal combustion power generator 2 arranged in parallel with the power system 1 is larger than the minimum target value will be described. The main body that controls the operation of FIG. 5 is the control unit 7C.

  As described above, which internal combustion power generator 2 among the plurality of internal combustion power generators 2 is parallel to or disconnected from the power system 1 at which timing depends on the renewable energy power generation on the corresponding day. It is obtained from a predetermined calculation formula based on the predicted value of the power generation output of the device 3 and the predicted value of the demand of the load 5. Said calculation is implement | achieved when the control part 7C performs the program data memorize | stored in the memory | storage part 7B in the supply-and-demand control apparatus 7. FIG. For example, according to the calculation result of the control unit 7C, when any one of the internal combustion power generation devices 2 is expected to be started in a short time in parallel with the electric power system 1, this internal combustion power is considered from the viewpoint of economy such as fuel consumption. It is desirable to supply power from the storage battery 4 to the load 5 without paralleling the power generation device 2 to the power system 1.

First, the supply and demand control device 7 determines whether or not it is necessary to set the second charge level T ₁ + α as a reference level to be compared with the charge level SOC of the storage battery 4 according to the calculation result of the control unit 7C (S201). ). When it is necessary to set the second charge level T ₁ + α (S201: YES), the supply and demand control device 7 generates a predetermined charge level α (> 0) and sets the second charge level T ₁ + α ( S202). The case where the setting of the second charge level T ₁ + α is necessary is, for example, a case where it is expected that any of the internal combustion power generation devices 2 needs to be started in a short time in parallel with the power system 1. is there.

Next, the supply and demand control device 7 determines whether or not the charge level SOC of the storage battery 4 is equal to or higher than the second charge level T ₁ + α (S203). When the charge level SOC of the storage battery 4 is less than the second charge level T ₁ + α (S203: NO), the discharge of the storage battery 4 is stopped (S = 0) (S204), and the internal combustion already in parallel with the power system 1 A command is output so that the load frequency control is performed only by the power generation device 2 (S205). Thus, since the discharge of the storage battery 4 stops at the second charge level T ₁ + α higher than the first charge level T _{1, the} internal combustion power generator 2 that is expected to be parallel to the power system 1 is disconnected. As it is, power can be supplied from the storage battery 4 to the load 5. The supply and demand control device 7, and outputs a command at step S205, the flow returns to the determination of the necessity of first charge level T ₁ or second charge level T ₁ + alpha settings in step S201.

  Here, the relationship between the power generation output of the internal combustion power generation device 2 and the output of the storage battery 4 when the supply and demand control device 7 executes Step S204 is expressed by Expression (4).

(However, ΣDG _ctl represents the total adjustment output when the N internal combustion power generation devices 2 parallel to the power system 1 perform load frequency control.)
That is, as conditions for stopping the discharge of the storage battery 4, the adjustment output ΣDG _ctl of the internal combustion power generation device 2 on the power supply side, the power generation output RE of the renewable energy power generation device 3, and the load 5 on the power demand side The internal combustion power generation device 2 outputs the adjustment output ΣDG _ctl with the load frequency controlled so that the difference from the total demand L becomes zero.

When the setting of the second charge level T ₁ + α is not necessary (S201: NO), the supply and demand control device 7 sets the predetermined charge level α to zero and sets the first charge level T ₁ (S206). The case where the setting of the second charge level T ₁ + α is unnecessary is a case where, for example, any of the internal combustion power generation devices 2 is expected not to be started in a short time in parallel with the power system 1. is there. In this case, even if the total generated power of the internal combustion power generation device 2 and the renewable energy power generation device 3 exceeds the total demand of the load 5, the power generation output of the internal combustion power generation device 2 performing the load frequency control is the minimum target value. The control (modes A to C) for discharging the storage battery 4 as much as possible is performed so that the control is performed so as not to fall below.

Next, the supply and demand control device 7 determines whether or not the charge level SOC of the storage battery 4 is equal to or higher than the first charge level T ₁ (S207). When the charge level SOC of the storage battery 4 is lower than the first charge level T ₁ (S207: NO), the supply and demand control device 7 executes the above steps S204 and S205, stops the discharge of the storage battery 4, and A command is output so that the load frequency control is performed only by the internal combustion power generator 2 that is already in parallel with the power generator 1. The supply and demand control device 7, and outputs a command at step S205, the flow returns to the determination of the necessity of first charge level T ₁ or second charge level T ₁ + alpha settings in step S201.

When the charge level SOC of the storage battery 4 is greater than or equal to the second charge level T ₁ + α (S203: YES) or greater than or equal to the first charge level T ₁ (S207: YES), the supply and demand controller 7 discharges the storage battery 4 One of the three modes A to C is selected (S208). In addition, as a selection method of three types of modes A to C, for example, a method in which an operator manually selects one of the three types of modes A to C, or the supply and demand control device 7 is in the three types of modes A to C. A method of selecting either one according to the condition including the total demand L of the load 5 is conceivable. In the former case, the supply and demand control device 7 determines that the charge level of the storage battery 4 is not less than the first charge level T ₁ or the second charge level T ₁ + α, for example, three types of modes A to C for the worker. Output an alarm to prompt selection. And the supply-and-demand control apparatus 7 can perform the mode which the worker selected, if the signal which informs that the worker selected any of three types of modes AC is received. In the latter case, for example, three types of modes A to C are respectively associated with three types of sizes of the total demand L of the load 5. Then, when the charge level of the storage battery 4 is equal to or higher than the first charge level T ₁ or the second charge level T ₁ + α, the supply and demand control device 7 determines the total demand L of the load 5 from among the three modes A to C. The mode corresponding to can be selected and executed.

When the mode A for discharging the storage battery 4 is selected (S208: A), the supply and demand control device 7 controls the storage battery 4 to discharge at a constant output (S209) and is parallel to the power system 1. A command is output so that the load frequency control is performed only by the internal combustion power generation device 2 that is in operation (S210). The supply and demand control device 7, and outputs a command at step S210, the flow returns to the determination of the necessity of first charge level T ₁ or second charge level T ₁ + alpha settings in step S201.

  Here, the relationship between the power generation output of the internal combustion power generation device 2 and the output of the storage battery 4 when the supply and demand control device 7 executes steps S209 and S210 in mode A is expressed by equation (5).

(However, S _fix represents the fixed output of the storage battery 4)
In other words, the internal combustion power generator 2 is adjusted by controlling the load frequency so that the storage battery 4 is discharged at a constant output S _fix while considering the power generation output RE of the renewable energy power generator 3 and the total demand L of the load 5. Output ΣDG _ctl .

When the mode B for discharging the storage battery 4 is selected (S208: B), the supply and demand control device 7 stops the load frequency control of the internal combustion power generation device 2 parallel to the power system 1, and this internal combustion The power generation output of the power generation device 2 is fixed to the minimum output that is the minimum target value (S211), and a command is output so that the storage battery 4 performs load frequency control (S212). The supply and demand control device 7, and outputs a command at step S212, the flow returns to the determination of the necessity of first charge level T ₁ or second charge level T ₁ + alpha settings in step S201.

  Here, the relationship between the power generation output of the internal combustion power generation device 2 and the output of the storage battery 4 when the supply and demand control device 7 executes steps S211 and S212 is expressed by equation (6).

(However, S _ctl represents the adjustment output when the storage battery 4 is performing the load frequency control, and ΣDG _min represents the sum of the minimum outputs of the N internal combustion power generation devices 2 arranged in parallel with the power system 1.)
That is, the storage battery 4 is subjected to load frequency control and adjusted output so that the internal combustion power generation device 2 outputs the minimum output ΣDG _min while considering the power generation output RE of the renewable energy power generation device 3 and the total demand L of the load 5. Output S _ctl .

When the mode C for discharging the storage battery 4 is selected (S208: C), the supply and demand control device 7 performs the load frequency control of the storage battery 4 (S213), and the internal combustion power generation parallel to the power system 1 The apparatus 2 also outputs a command to perform load frequency control (S214). The supply and demand control device 7, and outputs a command at step S214, the flow returns to the determination of the necessity of first charge level T ₁ or second charge level T ₁ + alpha settings in step S201.

  Here, the relationship between the power generation output of the internal combustion power generation device 2 and the output of the storage battery 4 when the supply and demand control device 7 executes steps S213 and S214 is expressed by equation (7).

In other words, the internal combustion power generator 2 outputs the adjusted output ΣDG _ctl while controlling the load frequency while considering the power generation output RE of the renewable energy power generator 3 and the total demand L of the load 5, and the storage battery 4 controls the load frequency. Then, control is performed so as to output the adjustment output _Sctl . As the distribution of the adjustment outputs ΣDG _ctl , S _ctl for the load 5, for example, proportional distribution or frequency distribution can be considered. Thus, while the internal combustion power generation device 2 and the storage battery 4 share the supply of power to the load 5, The storage battery 4 can be discharged.

<< Unit control operation >>
The details of step S102 of FIG. 4 for controlling the parallel and disconnection of the internal combustion power generation device 2 with respect to the power system 1 according to the fluctuation of the power generation output of the renewable energy power generation device 3 will be described.

  First, when any one of the above modes A to C is executed for the purpose of securing the amount of power supplied to the load 5, the supply and demand control device 7 applies to the power system 1 according to equations (8) and (9). It is determined whether or not the internal combustion power generator 2 should be paralleled or disconnected.

(Where ΣDG _max is the total of the rated outputs (maximum outputs) of the N internal combustion power generators 2 in parallel with the power system 1, and S _Ts is the load 5 until the internal combustion power generator 2 is activated. Output of the storage battery 4 capable of continuously supplying power to the battery (discharge: negative value), ε ₁ is a margin for fluctuations in demand of the load 5, ε _RE is a rapid decrease in the power generation output of the renewable energy generator 3 Even if it does, it represents the minimum expected output.)

(Where ΣDG _max is the total of the rated outputs of the N−1 internal combustion power generators 2 assumed to be in parallel with the power system 1, and ε ₂ represents a margin for fluctuations in the demand of the load 5.)
Here, even if the power generation output of the renewable energy power generation device 3 rapidly decreases, if, for example, 20% of the power generation output of the renewable energy power generation device 3 is expected to be minimal, ε _RE is 20% of this It represents the power generation output. Note that ε _RE is an expected value and may be omitted from the equations (8) and (9).

Equation (8) is obtained by calculating the load 5 including the margin ε ₁ when the sum of the rated output ΣDG _max of the N internal combustion power generation devices 2, the expected output ε _{RE of the} renewable energy power generation device 3, and the output S _Ts of the storage battery 4. It represents that it is less than the total demand L. That is, Expression (8) represents that the amount of power supplied to the load 5 is insufficient. Therefore, when the condition of Expression (8) is satisfied, the supply and demand control device 7 parallels one internal combustion power generation device 2 among the already disconnected internal combustion power generation devices 2 with respect to the power system 1. Command is output. One internal combustion power generator 2 is started in parallel with the power system 1 in response to this command. In this way, the number of internal combustion power generators 2 arranged in parallel with the power system 1 is changed from N to N + 1.

On the other hand, Equation (9) assumes that the number of internal combustion power generators 2 in parallel with the power system 1 has decreased from N to N−1, and the rating of N−1 internal combustion power generators 2 output ShigumaDG _max, expected output epsilon _RE renewable energy power generating apparatus 3, the sum of (discharge) output -S _Ts of the storage battery 4, indicating that it is the total demand L or more load 5 including a margin epsilon _2. That is, equation (9) represents that the amount of power supplied to the load 5 remains even if the number of the internal combustion power generation devices 2 decreases from the current N to N−1. Therefore, when the condition of Expression (9) is satisfied, the supply and demand control device 7 disconnects one internal combustion power generation device 2 from the internal combustion power generation devices 2 already in parallel with the power system 1. Command is output. One internal combustion power generator 2 is disconnected from the power system 1 in response to this command. In this way, the number of internal combustion power generators 2 arranged in parallel with the power system 1 decreases from N to N-1.

It can be seen that when the output _{STs of the} storage battery 4 increases, the chance of satisfying the condition of the equation (8) decreases, and the parallel arrangement of the internal combustion power generation devices 2 is suppressed. This also, in all times of supply and demand control operation, since the provided step (step S201~S203 of FIG. 5) that the storage battery 4 compares the charge level SOC first charge level T ₁ is greater than the second charge level T1 + alpha It can be understood that even when any of the internal combustion power generation devices 2 is expected to need to be started in a short time in parallel with the power system 1, the internal combustion power generation device 2 can be suppressed in parallel.

  In addition, the supply and demand control device 7 has an internal combustion system for the power system 1 according to the equation (10) for the purpose of securing a “lowering allowance (reduction margin)” that is an adjustment force that systematically lowers the output of the internal combustion power generation device 2. It is determined whether or not the power generator 2 should be paralleled or disconnected.

(However, ΣDG _min is the sum of the minimum outputs (minimum target values) of the N internal combustion power generators 2 in parallel with the power system 1 and ΔRE _i is the current output subtracted from the rated output of the renewable energy generator 3. (S _max represents the rated output (charge) of the storage battery 4)
ΔRE _i included in Expression (10) is expressed by Expression (11).

(However, ΣRE _max represents the sum of the rated output of the M stage of renewable energy power generating apparatus 3 connected to the electric power system.)
+ ΔRE _i indicates that the power generation output of the renewable energy power generation device 3 increases from the current output to the rated output. That is, + ΔRE _i represents a margin for reducing the power generation output of the internal combustion power generation device 2. Therefore, Expression (10) indicates that the power generation output of the renewable energy power generation device 3 increases to the rated output when the power generation output of the internal combustion power generation device 2 is at the minimum target value, and there is no allowance for lowering the internal combustion power generation device 2. Although the storage battery 4 has been charged to the rated output, the power supplied from the internal combustion power generation device 2 and the renewable energy power generation device 3 to the load 5 is surplus. Therefore, when the condition of Expression (10) is satisfied, the supply and demand control device 7 disconnects one internal combustion power generation device 2 from the internal combustion power generation devices 2 already in parallel with the power system 1. Command is output. One internal combustion power generator 2 is disconnected from the power system 1 in response to this command. In this way, the number of internal combustion power generators 2 arranged in parallel with the power system 1 decreases from N to N-1. However, even if the power generation output of the N-1 internal combustion power generation devices 2 is increased to the rated output, it should not be “raising power shortage” such that the amount of power supplied to the load 5 is insufficient.

  The supply and demand control device 7 follows the formula (12) in addition to the formula (10) for the purpose of securing “a raise margin (a surplus surplus power)” that is an adjustment force that systematically increases the output of the internal combustion power generation device 2. It is determined whether or not the internal combustion power generation apparatus 2 should be paralleled or disconnected from the power system 1.

(However, ΣDG _max is the sum of the rated outputs of N−1 internal combustion power generators 2 assumed to be in parallel with power system 1, ΔRE _d is the current output of renewable energy power generator 3, and S _max is (Represents the rated output (discharge: negative value) of the storage battery 4)
ΔRE _d included in Expression (12) is expressed by Expression (13).

(However, ΣRE represents the total current output of the M renewable energy power generation devices 3 connected to the power system.)
-ΔRE _d represents that the power generation output of the renewable energy power generation device 3 becomes zero from the current output. That is, −ΔRE _d represents the increase in the power generation output of the internal combustion power generation device 2. Therefore, equation (12) assumes that the number of internal combustion power generation devices 2 in parallel with the power system 1 has decreased from N to N−1, and the power generation output of the internal combustion power generation device 2 is the rated output. In this state, the power generation output of the renewable energy power generation device 3 becomes zero, and there is no need to raise the internal combustion power generation device 2, and the rated output of the storage battery 4 is supplied to the load 5. It represents that the electric power supplied from the energy power generation device 3 to the load 5 is surplus. Therefore, when the condition of Expression (12) is satisfied in addition to Expression (10), the supply / demand control apparatus 7 selects one internal combustion power generator 2 from the internal combustion power generation apparatus 2 already in parallel with the power system 1. It is better to output a command for disconnecting the power generation device 2. One internal combustion power generator 2 is disconnected from the power system 1 in response to this command. In this way, the number of internal combustion power generators 2 in parallel with the electric power system 1 decreases from N to N−1, but the lowering and raising costs of the N−1 internal combustion power generating devices 2 are secured. It should be noted that the equations (10) and (12) indicate that when the power generation output of the renewable energy power generation device 3 fluctuates and reaches a minimum output or a rated output, the internal combustion power generation device 2 is newly connected to the power system 1 It can be said that it is an equation for determining whether or not the supply amount of power to the load 5 becomes excessive or insufficient without disconnecting.

  When step S102 of FIG. 4 is executed, the parallelism and disconnection of the internal combustion power generator 2 with respect to the power system 1 are controlled in consideration of all the conditions of the equations (8), (9), (10), and (12), and the load 5 controls the number of internal combustion power generation devices 2 that supply power to the power.

  However, when the number of the renewable energy power generation devices 3 increases, all the conditions of the formulas (8), (9), (10), and (12) are satisfied in the control of the parallel and disconnection of the internal combustion power generation device 2 with respect to the power system 1. There is a high possibility that a satisfactory solution cannot be obtained. More specifically, one internal combustion power generation device 2 cannot be disconnected in order to secure the amount of power supplied to the load 5 even though the lowering allowance of the internal combustion power generation device 2 is expected to be insufficient. This is a case where the condition of Expression (12) is not satisfied when the condition of Expression (10) is satisfied. In this case, the supply and demand control device 7 switches the control method for paralleling and disconnecting the internal combustion power generation device 2 with respect to the power system 1 to one of the following methods A to F.

<Method A>
When the amount of power supplied to the load 5 is secured by the power generation output RE (current output) of the renewable energy power generation device 3 and the condition of equation (12) is satisfied when the power generation output RE is considered, the supply and demand control device 7 A command for disconnecting one internal combustion power generator 2 from the system 1 is output.

<Method B>
The future generation power RE ′ is predicted from the output fluctuation distribution in the future (for example, after several minutes) in consideration of the power generation output RE of the renewable energy power generation device 3, and the amount of power supplied to the load 5 is secured by the generation power RE ′. In consideration of the power generation output RE ′, when the condition of Expression (12) is satisfied, the supply and demand control device 7 outputs a command for disconnecting one internal combustion power generation device 2 from the power system 1.

<Method C>
The shortage ΔP _d of the lowering allowance of the internal combustion power generation device 2 is expressed by the equation (14) based on the equation (10).

The raising allowance ΔP _i of the internal combustion power generation device 2 is expressed by Expression (15) based on Expression (12).

If there is a deficiency in the allowance for lowering and raising the internal combustion power generator 2, select the one with the smaller absolute value of ΔP _d and ΔP _i (the one with the smaller expected frequency fluctuation) in terms of the amount of damage. To do. For example, when the absolute value of ΔP _d is larger between ΔP _d and ΔP _i , the supply and demand control device 7 disconnects one internal combustion power generation device 2 from the power system 1. That is, ΔP _d is a shortage of the lowering allowance, and if the value of ΔP _d is a positive value, it represents a shortage of the lowering allowance. Further, [Delta] P _i is a raised margin when the internal combustion power generation apparatus 2 and one disconnection from the power system 1 in order to solve the shortage of lower cost, the lack of increased cost if it is negative value is the value of [Delta] P _i Represent. Then, when one internal combustion power generation device 2 is disconnected and the raising allowance is insufficient, the shortage amount is reduced compared with the lowering allowance insufficient when the internal combustion power generation device 2 is not disconnected. Determine whether to line up.

<Method D>
In the internal combustion power generation device 2, securing the lowering allowance is given priority over securing the raising allowance. That is, regardless of whether the condition of Expression (12) is satisfied, when the condition of Expression (10) is satisfied, the supply and demand control device 7 outputs a command for disconnecting one internal combustion power generation device 2 from the power system 1. To do.

<Method E>
In consideration of the minimum expected output ε _RE when the power generation output RE of the renewable energy power generation device 3 rapidly decreases, the power supply amount to the load 5 is secured by the power generation output RE (current output), In consideration of the power generation output RE, when the condition of Expression (12) is satisfied, the supply and demand control device 7 outputs a command for disconnecting one internal combustion power generation device 2 from the power system 1.

<Method F>
When the number of the renewable energy power generation devices 3 decreases, the possibility that both the conditions of the expressions (10) and (12) are satisfied increases. Therefore, the supply and demand control apparatus 7 satisfies both the conditions of the expressions (10) and (12). Until then, a command for disconnecting the renewable energy power generation devices 3 one by one from the power system 1 is output. It is assumed that the order of discontinuation of the renewable energy power generation device 3 is, for example, the order in which the rated output is small.

<< Control operation when the power generation output of the internal combustion power generator is at the minimum output >>
As a result of controlling the number of internal combustion power generation devices 2 that are parallel or disconnected from the power system 1, the supply and demand control device 7 determines the number of internal combustion power generation devices 2 that are parallel to the power system 1 in advance. When the output value of each generated power of the internal combustion power generator 2 that is either the minimum number or the number that cannot be disconnected and is parallel to the power system 1 is below a predetermined minimum target value Therefore, it is necessary to perform control for charging the storage battery 4 with the power generation output of the renewable energy power generation device 3 so that the output value of each generated power of the internal combustion power generation device 2 does not fall below the minimum target value.

<Load frequency control by internal combustion power generator>
Details of step S105 in FIG. 4 will be described using one control method with reference to FIGS. The main body that controls the operation of FIG. 6 is the control unit 7C.

  First, the supply and demand control device 7 determines whether or not the output value of each generated power of the internal combustion power generation device 2 parallel to the power system 1 has reached a predetermined minimum target value while decreasing (S301). ). When the output value of each generated power of the internal combustion power generation device 2 reaches the minimum target value (S301: YES), the supply and demand control device 7 exceeds the minimum target value of the output value of each generated power of the internal combustion power generation device 2. In order to obtain a value, a command for changing the output S of the storage battery 4 to the output S + ΔS is output so that the output S of the storage battery 4 increases step by step with ΔS as a unit (S302). Note that ΔS is an amount set in advance. When the command in step S302 is output, the storage battery 4 charges the power generation output of the renewable energy power generation device 3 so that the output S of the storage battery 4 increases by ΔS. At this time, since the internal combustion power generation device 2 performs load frequency control over the entire power system 1, if the power generation output of the renewable energy power generation device 3 decreases as the storage battery 4 is charged, the internal combustion power generation The power generation output of the device 2 will increase. Then, step S301 is executed again. When the output value of each generated power of the internal combustion power generation device 2 does not exceed the minimum target value (S301: YES), the supply and demand control device 7 outputs a command for changing the output S + ΔS of the storage battery 4 to the output S + 2ΔS ( S302). When the command in step S302 is output, the storage battery 4 charges the power generation output of the renewable energy power generation device 3 so that the output S + ΔS of the storage battery 4 increases by ΔS. Steps S301 and S302 are repeatedly executed until the output value of each generated power of the internal combustion power generation device 2 exceeds the minimum target value.

  When the output value of each generated power of the internal combustion power generator 2 exceeds the minimum target value (S302: NO), the supply and demand controller 7 determines that the output value of each generated power of the internal combustion power generator 2 is the minimum target value + ΔS + ε ( It is determined whether or not ε <ΔS) is exceeded (S303). For convenience of explanation, it is assumed that the output of the storage battery 4 when executing step S303 for the first time is S. When the output value of each generated power of the internal combustion power generation device 2 exceeds the minimum target value + ΔS + ε (S303: YES), the supply and demand control device 7 sets the output value of each generated power of the internal combustion power generation device 2 as the minimum target value. A command for changing the output S of the storage battery 4 to the output S−ΔS is output so that the output S of the storage battery 4 decreases step by step with ΔS as a unit in order to obtain a value between the minimum target value + ΔS. (S304). When the command in step S304 is output, the storage battery 4 is discharged to the load 5 so that the output S of the storage battery 4 is decreased by ΔS. At this time, since the internal combustion power generation apparatus 2 performs load frequency control over the entire power system 1, the power generation output of the internal combustion power generation apparatus 2 decreases as the storage battery 4 is discharged. Then, step S301 is executed again. When the output value of each generated electric power of the internal combustion power generation device 2 continues to exceed the minimum target value + ΔS + ε (S303: YES), the supply and demand control device 7 changes the output S-ΔS of the storage battery 4 to the output S-2ΔS. Command is output (S304). When the command in step S304 is output, the storage battery 4 is discharged to the load 5 so that the output S-ΔS of the storage battery 4 is decreased by ΔS. Steps S301, S303, and S304 are repeatedly executed until the output value of each generated power of the internal combustion power generation device 2 falls below the minimum target value + ΔS + ε.

  When the output value of each generated electric power of the internal combustion power generator 2 is below the minimum target value + ΔS + ε (S303: NO), it is determined whether or not the output S of the storage battery 4 is a negative value (S305). When the output S of the storage battery 4 is a positive value (S305: NO), the storage battery 4 is being charged, so step S301 is executed again.

  When the output S of the storage battery 4 is a negative value (S305: YES), since the storage battery 4 is discharged, that is, the internal combustion power generator 2 can reduce the generated power without depending on the storage battery 4. Since there is a sufficient margin, the supply and demand control device 7 outputs a command for stopping charging / discharging of the storage battery 4 (S306). When the command of step S306 is output, the storage battery 4 stops charging and discharging, and the output S of the storage battery 4 becomes zero.

  The operation of FIG. 6 will be described with reference to FIG. The horizontal axis represents time, and the vertical axis represents the power generation output level of the internal combustion power generation device 2. The solid line indicates the power generation output of the internal combustion power generation device 2 when the storage battery 4 is not charged / discharged, which is a value obtained by subtracting the power generation output of the renewable energy power generation device 3 from the total demand of the load 5. The alternate long and short dash line indicates how the output S of the storage battery 4 increases or decreases with ΔS as a unit. A downward change in the output S of the storage battery 4 indicates ΔS charging, and an upward change in the output S of the storage battery 4 indicates ΔS discharge. The thick broken line indicates the power generation output of the internal combustion power generation apparatus 2 when the storage battery 4 is charged and discharged. The thin broken line indicates the minimum target value of the internal combustion power generation device 2.

  When the power generation output of the internal combustion power generation device 2 decreases and reaches the minimum target value, the storage battery 4 generates power from the renewable energy power generation device 3 so that the output S of the storage battery 4 at this time increases by one step with ΔS as a unit. The output is charged, and accordingly, the power generation output of the internal combustion power generation device 2 increases (time t1, t2, t3). When the power generation output of the internal combustion power generator 2 exceeds the minimum target value + ΔS + ε, the storage battery 4 is discharged to the load 5 so that the output S of the storage battery 4 at this time decreases by one step with ΔS as a unit. Accordingly, the power generation output of the internal combustion power generation device 2 decreases (time t4, t5, t6). After time t6, the power generation output of the internal combustion power generation device 2 exceeds the minimum target value, and charging / discharging of the storage battery 4 stops.

  The operation of FIG. 6 will be described with reference to FIG.

  When the power generation output of the internal combustion power generation device 2 falls below the minimum target value, the output S of the storage battery 4 at this time increases by ΔS, and thus the power generation output of the internal combustion power generation device 2 increases. On the other hand, when the power generation output of the internal combustion power generation apparatus 2 exceeds the minimum target value + ΔS + ε, the output S of the storage battery 4 at this time decreases by ΔS, and thus the power generation output of the internal combustion power generation apparatus 2 decreases. The power generation output of the internal combustion power generator 2 changes between the minimum target value and the minimum target value + ΔS according to the charge / discharge of the storage battery 4.

  As described above, when the power generation output of the internal combustion power generation device 2 falls below the minimum target value, the storage battery 4 charges the power generation output of the renewable energy power generation device 3, so that the power generation output of the internal combustion power generation device 2 is the minimum target value. It is maintained above, and it becomes possible to secure the allowance for lowering the internal combustion power generation device 2. Moreover, since the internal combustion power generation device 2 continues the load frequency control while the storage battery 4 is charging / discharging, it is possible to perform the load frequency control with good continuity in the power system 1. Further, in step S303, the power generation output of the internal combustion power generation device 2 is compared, and since ε smaller than ΔS, which is a change unit when increasing or decreasing the output S of the storage battery 4, is included, the internal combustion power generation device The power generation output of 2 can be converged within the range of one step between the lowest target value and the lowest target value + ΔS (minimum target value + ε).

<Load frequency control by storage battery>
Details of step S105 in FIG. 4 will be described using another control method with reference to FIGS. The main body that controls the operation of FIG. 9 is the control unit 7C.

  First, when the output value of each generated power of the internal combustion power generation device 2 parallel to the power system 1 reaches a predetermined minimum target value while decreasing, the supply and demand control device 7 determines that the internal combustion power generation device 2 The load frequency control is stopped, and a command for fixing the power generation output of the internal combustion power generation device 2 to the minimum target value is output (S401). When the command in step S401 is output, the load frequency control by the internal combustion power generation device 2 is stopped, and the power generation output of the internal combustion power generation device 2 is fixed to the minimum target value.

When the total power output of the internal combustion power generation device 2 and the renewable energy power generation device 3 exceeds the total demand of the load 5 in a state where the power generation output of the internal combustion power generation device 2 is fixed to the minimum target value, the renewable energy power generation device Therefore, it is necessary to charge only the surplus power of the renewable energy power generation device 3 using the storage battery 4. Therefore, during the period in which the power generation output of the internal combustion power generation device 2 is fixed to the minimum target value, the supply / demand control device 7 charges the storage battery 4 so that the demand and supply of power with the load 5 are balanced. The command for performing the load frequency control is output (S402). When the command in step S402 is output, the adjustment output S _ctl of the storage battery 4 is controlled so that the condition shown in the following equation (16) is satisfied.

(However, Sctl = −AR.)
The supply and demand control device 7 determines whether or not the output S of the storage battery 4 is less than a predetermined negative value −ε as a result of the load frequency control performed by the storage battery 4 (S403). When the output S of the storage battery 4 is greater than or equal to -ε (S403: NO), since the discharge amount of the storage battery 4 has not reached the amount corresponding to -ε, the supply and demand control device 7 loads the storage battery 4 while charging it. A command for performing frequency control is continuously output (S402). On the other hand, when the output S of the storage battery 4 is less than −ε (S403: YES), the supply / demand control device 7 charges / discharges the storage battery 4 because the discharge amount of the storage battery 4 has reached an amount corresponding to −ε. A command for stopping is output (S404). When the command in step S404 is output, the storage battery 4 stops charging / discharging, and the output S of the storage battery 4 becomes zero. Therefore, the load frequency control by the storage battery 4 is stopped. Then, the supply and demand control device 7 releases the state where the power generation output of the internal combustion power generation device 2 is fixed to the minimum target value, and outputs a command for restarting the load frequency control by the internal combustion power generation device 2 (S405). . When the command in step S405 is output, the load frequency control by the internal combustion power generation device 2 is resumed, and the power generation output of the internal combustion power generation device 2 changes according to the load frequency control.

  The operation of FIG. 9 will be described with reference to FIG. The horizontal axis represents time, and the vertical axis represents the power generation output level of the internal combustion power generation device 2. A thick solid line indicates a power generation output of the internal combustion power generation apparatus 2 when the load frequency control by the storage battery 4 is not performed, and a value obtained by subtracting the power generation output of the renewable energy power generation apparatus 3 from the total demand of the load 5. Yes. The thin solid line indicates the power generation output of the internal combustion power generation apparatus 2 when the load frequency control by the storage battery 4 is performed. The thin broken line indicates the minimum target value of the internal combustion power generation device 2.

  When the power generation output of the internal combustion power generation apparatus 2 reaches the minimum target value while decreasing, the load frequency control by the internal combustion power generation apparatus 2 stops and the power generation output of the internal combustion power generation apparatus 2 is fixed to the minimum target value (thin solid line). Is done. On the other hand, the storage battery 4 performs load frequency control while charging so that the demand and supply of power among the internal combustion power generation device 2 and the renewable energy power generation device 3 and the load 5 are balanced (time t1). When the discharge amount of the storage battery 4 reaches an amount corresponding to −ε, the load frequency control by the storage battery 4 is stopped, the state where the power generation output of the internal combustion power generation device 2 is fixed to the minimum target value is released, and the internal combustion engine The power generator 2 resumes the load frequency control (time t2). Since ε is taken into account when switching the load frequency control from the storage battery 4 to the internal combustion power generation device 2, the storage battery 4 stops charging after exceeding the minimum target value. Therefore, chattering in which the load frequency control frequently switches between the internal combustion power generation device 2 and the storage battery 4 can be prevented.

  As described above, load frequency control is performed so that the demand and supply of power to and from the load 5 are balanced, and the plurality of internal combustion power generation devices 2 that supply power to the load 5 and the power to the load 5 are supplied. In the power system 1 to which the supplied renewable energy power generation device 3 and the storage battery 4 that charges the generated power of the renewable energy power generation device 3 are connected, parallel and disconnection of the plurality of internal combustion power generation devices 2 are controlled. The supply and demand control device 7, which is a rated output value of the internal combustion power generation device 2 that is parallel to the power system 1 among the plurality of internal combustion power generation devices 2, and the internal combustion power generation device 2 that is parallel to the power system 1. A function for determining whether or not the first added value of the output value of the storage battery 4 that continuously supplies power to the load 5 until it is activated is insufficient with respect to the total demand of the load 5; 1 added value against total demand for load 5 If you are missing Te, a control unit 7C to perform a function for parallel a predetermined internal combustion power generation device 2 which is Kairetsu from the power system 1 of the plurality of internal combustion power generation device 2. Thereby, even when the power generation output of the renewable energy power generation device 3 fluctuates, it is possible to control the parallelism of the internal combustion power generation device 2 with respect to the power system so that the amount of power supplied to the load 5 can be optimally secured. Become. Here, the total demand of the load 5 may be a value obtained by subtracting the power generation output that can be expected at the minimum even if the power generation output of the renewable energy power generation device 3 decreases. Thereby, it becomes possible to control parallelism of the internal combustion power generation device 2 with respect to the power system 1 in consideration of the generated power of the renewable energy power generation device 3.

  Further, the control unit 7C has each rated output value when it is assumed that the predetermined internal combustion power generation device 2 is disconnected from the internal combustion power generation device 2 that is parallel to the power system 1 among the plurality of internal combustion power generation devices 2. And the output value of the storage battery 4 that continuously supplies power to the load 5 until the internal combustion power generator 2 in parallel with the power system 1 is started up, If the second added value is not insufficient with respect to the total demand of the load 5, the predetermined internal combustion power generator 2 that is parallel to the power system 1 is solved. And the function to queue. Thereby, even when the power generation output of the renewable energy power generation device 3 fluctuates, it is possible to control the disconnection of the internal combustion power generation device 2 with respect to the power system so that the amount of power supplied to the load 5 can be optimally secured. become. Here, the total demand of the load 5 may be a value obtained by subtracting the power generation output that can be expected at the minimum even if the power generation output of the renewable energy power generation device 3 decreases. Thereby, it is possible to control the disconnection of the internal combustion power generation device 2 with respect to the power system 1 in consideration of the generated power of the renewable energy power generation device 3.

  The control unit 7C also sets the minimum target value of the internal combustion power generation device 2 that is parallel to the power system 1 among the plurality of internal combustion power generation devices 2, the output value of the renewable energy power generation device 3, and the renewable energy. The third added value of the fluctuation value when the output value of the power generation device 3 increases to the rated output value is insufficient with respect to the fourth added value of the total demand of the load 5 and the rated output value of the storage battery 4. A function for determining whether or not the third addition value is insufficient with respect to the fourth addition value, and a function for disconnecting the predetermined internal combustion power generator 2 that is parallel to the power system 1. Run. As a result, it is possible to secure a reduction allowance for the internal combustion power generation device 2.

  Further, the control unit 7C has each rated output value when it is assumed that the predetermined internal combustion power generation device 2 is disconnected from the internal combustion power generation device 2 that is parallel to the power system 1 among the plurality of internal combustion power generation devices 2. The first subtracted value of the sum of the output value of the renewable energy power generator 3 and the fluctuation value when the output value of the renewable energy power generator 3 becomes zero is the total demand of the load 5 and the storage battery The function of determining whether or not the second subtraction value with the rated output value of 4 is insufficient, and when the first subtraction value is not insufficient with respect to the second subtraction value, the power system 1 is paralleled. The predetermined internal combustion power generation device 2 is disconnected. As a result, it is possible to secure a margin for raising the internal combustion power generation device 2.

  The present embodiment is intended to facilitate understanding of the present invention, and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Electric power system 2 Internal combustion power generation device 3 Renewable energy power generation device 4 Storage battery 5 Load 7 Supply-demand control device 7C Control part

Claims (11)

Load frequency control is performed so that the demand and supply of power between the load and the load are balanced, and a plurality of first power generation devices that supply power to the load, and power is supplied to the load using renewable energy In a power system to which a second power generation device and a storage battery that charges the generated power of the second power generation device are connected, a supply and demand control device that controls parallel and disconnection of the plurality of first power generation devices,
Each rated output value of the first power generator parallel to the power grid among the plurality of first power generators and power to the load until the first power generator parallel to the power grid is activated A first determination unit that determines whether or not the first added value of the output value of the storage battery that continuously supplies is insufficient with respect to the total demand of the load;
When the first addition value is insufficient with respect to the total demand of the load, a first control for paralleling a predetermined first power generation device disconnected from the power system among the plurality of first power generation devices. And
Supply and demand control apparatus characterized by comprising. The supply and demand control apparatus according to claim 1, wherein the total demand of the load is a value obtained by subtracting a power generation output that can be expected at a minimum even if the power generation output of the second power generation apparatus decreases. Each rated output value when it is assumed that a predetermined first power generator is disconnected from a first power generator parallel to the power system among the plurality of first power generators, and parallel to the power system Whether or not the second added value of the discharge output value of the storage battery that continuously supplies power to the load until the first power generator is activated is insufficient with respect to the total demand of the load A second determination unit for determining
A second control unit that disconnects a predetermined first power generator in parallel with the power system, when the second added value is not insufficient with respect to the total demand of the load;
The supply and demand control device according to claim 1, further comprising: The supply and demand control apparatus according to claim 3, wherein the total demand of the load is a value obtained by subtracting a power generation output that can be expected at a minimum even if the power generation output of the second power generation apparatus decreases. Among the plurality of first power generators, the lowest target value of the first power generator paralleled in the power system, the output value of the second power generator, and the output value of the second power generator are rated output values. A third determination unit that determines whether or not the third addition value of the fluctuation value in the case of increasing up to the fourth addition value of the total demand of the load and the rated output value of the storage battery is excessive When,
A third control unit that disconnects a predetermined first power generator in parallel with the power system, when the third addition value is excessive with respect to the fourth addition value;
The supply and demand control device according to claim 3, further comprising: Each rated output value and the output value of the second power generator when it is assumed that a predetermined first power generator is disconnected from the first power generator parallel to the power grid among the plurality of first power generators. And the first subtraction value of the fluctuation value when the output value of the second power generator becomes zero is the second subtraction of the total demand of the load and the rated discharge output value of the storage battery A fourth determination unit for determining whether or not the value is insufficient;
If the first subtraction value is not insufficient with respect to the second subtraction value, a fourth control unit for disconnecting a predetermined first power generator in parallel with the power system;
The supply and demand control device according to claim 5, further comprising: The supply and demand control apparatus according to any one of claims 1 to 6, wherein the first power generation apparatus is an internal combustion power generation apparatus. Load frequency control is performed so that the demand and supply of power between the load and the load are balanced, and a plurality of first power generation devices that supply power to the load, and power is supplied to the load using renewable energy In a power system to which a second power generation device and a storage battery that charges the generated power of the second power generation device are connected, a supply and demand control method for controlling parallel and disconnection of the plurality of first power generation devices,
Each rated output value of the first power generator parallel to the power grid among the plurality of first power generators and power to the load until the first power generator parallel to the power grid is activated Determining whether or not the first added value of the discharge output value of the storage battery that continuously supplies is insufficient with respect to the total demand of the load,
When the first added value is insufficient with respect to the total demand of the load, a predetermined first power generation device disconnected from the power system among the plurality of first power generation devices is arranged in parallel. Supply and demand control method. Each rated output value when it is assumed that a predetermined first power generator is disconnected from a first power generator parallel to the power system among the plurality of first power generators, and parallel to the power system Whether or not the second added value of the discharge output value of the storage battery that continuously supplies power to the load until the first power generator is activated is insufficient with respect to the total demand of the load Determine
9. The supply and demand according to claim 8, wherein when the second added value is not insufficient with respect to the total demand of the load, the predetermined first power generation device arranged in parallel with the power system is disconnected. Control method. Among the plurality of first power generators, the lowest target value of the first power generator paralleled in the power system, the output value of the second power generator, and the output value of the second power generator are rated output values. Determining whether or not the third added value of the fluctuation value when increasing up to the fourth added value of the total demand of the load and the rated output value of the storage battery is excessive,
The supply and demand control according to claim 9, wherein when the third addition value is excessive with respect to the fourth addition value, a predetermined first power generator parallel to the power system is disconnected. Method. Each rated output value and the output value of the second power generator when it is assumed that a predetermined first power generator is disconnected from the first power generator parallel to the power grid among the plurality of first power generators. And the first subtraction value of the fluctuation value when the output value of the second power generator becomes zero is the second subtraction of the total demand of the load and the rated discharge output value of the storage battery Determine if the value is missing,
11. The supply and demand according to claim 10, wherein when the first subtraction value is not insufficient with respect to the second subtraction value, a predetermined first power generation device parallel to the power system is disconnected. Control method.

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