Hybrid power generation system and control methods of the hybrid power generation system

Abstract

A hybrid power generation system comprising: a renewable energy power generation device capable of generating electricity using renewable energy; a rotary power generation device connected to an alternating current system common with the renewable energy power generation device, wherein the rotary power generation device is capable of generating energy in such a way as to reduce output fluctuation of the renewable energy power generation device;and a control device for controlling the rotary power generating device so that a rotational speed of the rotary power generating device reaches a target rotational speed, wherein the hybrid power generating system comprises: a fluctuation determination section for determining whether a fluctuation amount of renewable energy supplied to the renewable energy power generating device or an output of the renewable energy power generating device exceeds a predetermined value;and a correction value calculation section for calculating a correction value of the control parameter based on the fluctuation amount, and wherein the control device controls the rotary power generating device on the basis of a control parameter obtained by adding the correction value calculated by the correction value calculation section as a forward component when the fluctuation determination section determines that the fluctuation amount of renewable energy supplied to the renewable energy power generating device or the output of the renewable energy power generating device exceeds the predetermined value.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a hybrid power generation system comprising a renewable energy power generation device and a rotary power generation device connected to a common alternating current system, and to a method for controlling the hybrid power generation system. STATE OF THE ART

[0002] In recent years, a power generation system incorporating a renewable energy power generation device has become widespread. This device generates electricity by utilizing renewable energy sources such as solar or wind power as a clean energy source, while minimizing environmental impact. The amount of electricity generated by the renewable energy power generation device depends on the amount of renewable energy supplied, and the device is significantly affected by external factors such as weather conditions. Therefore, ensuring the stability of the electricity generation output is a key consideration for renewable energy power generation devices.

[0003] To stabilize the amount of electricity generated in the renewable energy power generation device, a so-called hybrid power generation system is known, for example, which is configured to connect a rotary power generation device, which can be driven by a power source such as a motor, to a power system common to the renewable energy power generation device (Patent Document 1). In this type of hybrid power generation system, the amount of electricity generated is stabilized by using the rotary power generation device to cover fluctuations in renewable energy production due to weather conditions. Citation list for patent literature

[0004] Patent Document 1: JPH4-372528A SUMMARY Technical Problem

[0005] In the hybrid power generation system described above, the amount of electricity generated is stabilized by controlling the drive of the rotary power generator in accordance with the fluctuation of the renewable energy supply. However, if the fluctuation of the renewable energy supply exceeds a predetermined value, the rotational speed of the rotary power generator is temporarily reduced by the load fluctuation, thus lowering the output frequency. This phenomenon occurs, for example, when a solar panel is used as a renewable energy power generator and the solar irradiance on the panel decreases rapidly when the weather changes from sunny to cloudy.Since the decrease in output frequency negatively affects the power grid into which the electricity is fed, the rotary power generating device must be disconnected from the power grid, making it impossible to stabilize the amount of electricity generated.

[0006] To avoid such a disconnection of the rotary power generation device, a hybrid power generation system is known that also includes an electrical storage device which can be connected to the power grid. In the system described above, the power generation output is stabilized by connecting the electrical storage device to the power grid instead of the rotary power generation device. The rotary power generation device can be switched off when the fluctuating amount of renewable energy exceeds a predetermined value. The electrical storage device uses a lithium-ion battery or similar device to store energy in advance. However, in large power generation systems that supply electricity to infrastructure, a large capacity for the electrical storage device is required, which makes the electrical storage device extremely expensive.

[0007] At least one embodiment of the present invention is made in consideration of the above, and an objective of the present invention is to provide a hybrid power generation system capable of cost-effectively implementing output stabilization when renewable energy fluctuates, and a control method for the hybrid power generation system. Solution to the problem

[0008] (1) To solve the problems described above, a hybrid power generation system according to at least one embodiment of the present invention is a hybrid power generation system comprising a renewable energy power generation device capable of generating electricity using renewable energy, a rotary power generation device connected to an AC system together with the renewable energy power generation device, the rotary power generation device capable of generating energy so that an output fluctuation of the renewable energy power generation device is reduced, and a control device for controlling the rotary power generation device so that a rotation speed of the rotary power generation device reaches a target rotation speed.The hybrid power generation system includes a fluctuation detection section to determine whether the fluctuation amount of renewable energy supplied to the renewable energy power generation device, or the output of the renewable energy power generation device, exceeds a predetermined value, and a correction value calculation section to calculate a correction value for the control parameter based on the fluctuation amount. The control device controls the rotary power generation device based on a control parameter obtained by adding the correction value calculated by the correction value calculation section as a forward component when the fluctuation detection section determines that the fluctuation amount of the renewable energy supplied to the rotary power generation device, or the output of the rotary power generation device, exceeds the predetermined value.

[0009] In the above configuration (1), if the fluctuation in the renewable energy or the output is such that the rotational speed of the rotary power generating device decreases, the correction value of the control parameter of the rotary power generating device is obtained on the basis of the amount of fluctuation in the renewable energy or the amount of fluctuation in the output of the renewable energy power generating device that occurs temporarily before the decrease in the rotational speed of the rotary power generating device. The correction value is added to the control parameter as a forward component, thereby suppressing the decrease in rotational speed of the rotary power generation device. This design of the rotary power generation device's control system makes it possible to achieve cost-effective output stabilization even with fluctuating renewable energy sources.

[0010] (2) In some embodiments, the control device in the above configuration (1) performs feedback control of the control parameter based on a difference between the target rotational speed and an actual measured rotational speed of the rotary current generating device.

[0011] In the configuration above (2), the correction value is added as a forward component to the control parameter used for feedback control. This makes it possible to take into account the fluctuations of the renewable energy or the fluctuations in the output of the renewable energy power generation device at an early stage and to implement stabilization control with excellent responsiveness.

[0012] (3) In some embodiments, in the configuration (2) above, the control device temporarily reduces a gain when performing feedback control of the control parameter when the fluctuation determination section determines that the amount of fluctuation of renewable energy supplied to the renewable energy power generation device or the output of the renewable energy power generation device exceeds the predetermined value.

[0013] In the configuration above (3), the feedback control gain of the control parameter is temporarily reduced when the fluctuation in the renewable energy or the output is such that the rotational speed of the rotary power generation device decreases, thereby emphasizing the forward component added to the control parameter. In this way, it is possible to suppress the decrease in the rotational speed of the rotary power generation device more effectively.

[0014] (4) In some embodiments, in one of the configurations (1) to (3) above, the hybrid power generation system further includes a memory section for storing reference data that defines a relationship between the fluctuation amount and the correction value for each operating state of the rotary power generation device, and an operating state detection section for detecting the operating state of the rotary power generation device. The correction value calculation section calculates the correction value of the control parameter based on the fluctuation amount, using the reference data corresponding to the operating state detected by the operating state detection section.

[0015] With the configuration above (4), the reference data defined for each operating state of the rotary power generation device are used to calculate the correction value added to the control parameter. This makes it possible to accurately determine the correction value added to the control parameter according to the operating state.

[0016] (5) In some embodiments, the hybrid power generation system in one of the above configurations (1) to (4) includes an electrical storage device configured to be connected to the AC system to reduce the output fluctuation of the renewable energy power generation device together with the rotary power generation device.

[0017] In the configuration described above (5), the hybrid power generation system also includes the electrical storage device, which is configured to be connected to the AC system. This reduces the output fluctuation of the renewable energy generator, along with the rotary generator, when renewable energy fluctuates. In the presented configuration, output stabilization during renewable energy fluctuations is achieved by adding the correction value to the rotary generator's control parameter as the forward component, as described above. Therefore, even with the electrical storage device described above, it is possible to keep its capacity low (or even omit the electrical storage device altogether). This allows for a cost-effective system with excellent stabilization.

[0018] (6) In some embodiments, in one of the above configurations (1) to (5), the renewable energy is solar energy.

[0019] With the above configuration (6) it is possible to implement power stabilization cost-effectively in the hybrid power generation system that uses solar energy as a renewable energy source, even if solar energy fluctuates due to a change in weather.

[0020] (7) In some embodiments, in one of the above configurations (1) to (5), the renewable energy is wind energy.

[0021] With the above configuration (7) it is possible to implement power stabilization cost-effectively in the hybrid power generation system that uses wind energy as a renewable energy source, even if the wind energy fluctuates due to a change in the weather.

[0022] (8) In some embodiments, in any of the above configurations (1) to (7), the rotary power generating device includes a motor as a power source, and the control parameter is a drive amount of an actuator for adjusting a fuel injection amount of the motor.

[0023] Since, in the above configuration (8), the correction value is added as a forward component to the actuator's drive parameter to adjust the amount of fuel injected by the motor serving as the energy source for the rotary power generation device, it is possible to achieve cost-effective stabilization of the system performance.

[0024] (9) To solve the problems described above, a control method of a hybrid power generation system according to at least one embodiment of the present invention is a control method of a hybrid power generation system comprising a renewable energy power generation device capable of generating electricity using renewable energy, a rotary power generation device connected to an AC power grid common with the renewable energy power generation device, wherein the rotary power generation device is capable of generating electricity so that an output fluctuation of the renewable energy power generation device is reduced, and a control device for controlling the rotary power generation device so that a rotation speed of the rotary power generation device reaches a target rotation speed.The control procedure includes a fluctuation determination step to determine whether a fluctuation amount of renewable energy supplied to the renewable energy power generation device or an output of the renewable energy power generation device exceeds a predetermined value, and a control step to control the rotary power generation device so that the rotational speed of the rotary power generation device reaches the target rotational speed.If the fluctuation determination section determines that the fluctuation amount of renewable energy supplied to the renewable energy power generation device, or the output of the renewable energy power generation device, exceeds the predetermined value, the control step controls the rotary power generation device based on a control parameter obtained by adding a correction value calculated on the basis of the fluctuation amount as a forward component.

[0025] In the above method (9), if there is a fluctuation in the renewable energy supply that causes the rotational speed of the rotary power generation device to decrease, the correction value of the control parameter of the rotary power generation device is obtained based on the magnitude of the fluctuation in the renewable energy supply or the magnitude of the fluctuation in the power output of the renewable energy power generation device that occurs temporarily before the decrease in the rotational speed of the rotary power generation device. The correction value is added to the control parameter as a forward component and thereby suppresses the decrease in the rotational speed of the rotary power generation device. The design of the control system of the rotary power generation device makes it possible to achieve power stabilization cost-effectively in the case of fluctuating renewable energy. Beneficial effects

[0026] According to at least one embodiment of the present invention, it is possible to provide a hybrid power generation system that is able to implement power stabilization cost-effectively when renewable energy fluctuates, and a control method for the hybrid power generation system. List of characters Fig. Figure 1 is an overall configuration diagram of a hybrid power generation system according to at least one embodiment of the present invention. Fig. Figure 2 is a schematic diagram showing the detailed configuration of a rotary power generating device in Fig. 1 shows. Fig. 3 is a block diagram of the configuration, which functionally represents an internal configuration of a controller in Fig. 1 shows. Fig. Figure 4 is a flowchart showing the steps of a control procedure of the hybrid power generation system according to at least one embodiment of the present invention. Fig. Figure 5 shows diagrams representing time transitions of renewable energy, an output of a renewable energy power generation device, and an operating state (output) or output frequency of the rotary power generation device. DETAILED DESCRIPTION

[0027] Some embodiments of the present invention are described below with reference to the accompanying drawings. However, unless specifically indicated, it is intended that dimensions, materials, shapes, relative positions, and the like of components described or shown in the drawings as embodiments are to be interpreted as illustrative only and are not intended to limit the scope of the present invention.

[0028] Fig. Figure 1 is an overall configuration diagram of a hybrid power generation system. 100 according to at least one embodiment of the present invention. The hybrid power generation system 100 includes a renewable energy power generation device 300 , a rotary current generating device 400 , an electrical storage device 500 and a control device 600, which run parallel to a common alternating current system 200 are connected.

[0029] The alternating current system 200 This is an energy system for distributing alternating current to a consumer (not shown). The alternating current power distributed by the AC system 200 has a constant frequency (e.g., 50 Hz or 60 Hz), and a predetermined capacity according to the consumer is supplied by the hybrid power generation system. 100 ensured.

[0030] The renewable energy power generation device 300 A renewable energy power generation device is a power generation device capable of producing electricity using renewable energy sources. More specifically, it is a renewable energy power generation device. 300For example, a solar module that uses solar energy as a renewable energy source, or a wind power generator that uses wind energy as a renewable energy source, but it can also be a power generation device of various other forms that utilize renewable energy. The following description essentially assumes a solar panel that uses solar energy as a renewable energy power generation device. 300 The present invention is also applicable to power generation devices of other forms that use renewable energy, unless expressly stated otherwise.

[0031] In the renewable energy power generation device 300Electricity is generated in accordance with a certain amount of renewable energy input. Therefore, if the amount of renewable energy input changes due to weather conditions, the amount of electricity generated by the renewable energy power generation device will also fluctuate. 300 For example, the amount of solar energy supplied decreases when the weather changes from sunny to cloudy, and so does the amount of electricity generated by the renewable energy power generation device. 300 reduced. Therefore, the amount of electricity generated by the renewable energy power generation device depends on 300 from the amount of renewable energy supplied.

[0032] The renewable energy power generation device 300is equipped with a power conditioner 310 on one output side. The power conditioner 310 is configured to include various power components such as a DC / DC converter and an AC / DC converter, and the output from the renewable energy power generation device. 300 is converted so that it conforms to a specification that is in the alternating current system 200 is required.

[0033] The renewable energy power generation device 300 includes a renewable energy detection sensor 320 , to record the amount of renewable energy supplied, and an output recording sensor 330 (Electricity generation amount) of the renewable energy power generation device 300 Only one of the renewable energy detection sensors can be used. 320 and the output capture sensor 330 be planned.

[0034] The rotary power generating device400 contains a motor 410 , which serves as a power source, and a generator 420 , which is from the engine 410 is powered. The engine 410 An internal combustion engine is capable of generating energy by consuming a fossil fuel, while a diesel engine, for example, is capable of outputting energy by consuming a light petroleum fuel. An output shaft of the engine 410 is with the generator 420 coupled, and the engine's performance 410 will be connected to the generator 420 transmitted, thereby generating electricity. The generator 420 For example, a rotary machine contains a rotor to which the motor's output shaft is coupled, and a stator arranged around the rotor.

[0035] Fig. Figure 2 is a schematic diagram showing the detailed configuration of the rotary power generation device.400 in Fig. 1 shows. The motor serving as an energy source 410 is via a flywheel 411 with the generator 420 connected. To the flywheel 411 is a rotational speed detection sensor 412 attached, and a measurement result from the rotational speed measurement sensor s 412 is fed into a controller. 414 entered. The controller control 414 It controls, as a control parameter, an actuator opening degree, which is a drive amount (rack amount) of a controller actuator. 416 for adjusting the amount of fuel injected, which is supplied by a fuel injection pump. 415 of the engine 410 is delivered. The controller 414 sets the rotational speed of the motor 410 (or the generator) 420) by performing feedback control of the actuator opening degree, which is the control parameter, based on a difference between a target frequency and a detection value of the rotational speed detection sensor s 412 and controlling the output frequency to the target frequency.

[0036] Returning to Fig. 1 stores the electrical storage device 500 together with the previously mentioned rotary power generating device 400 Energy supplied to the alternating current system 200 It is to be supplied when the fluctuation of renewable energy exceeds the predetermined value. The electrical storage device 500 For example, it uses a lithium-ion battery to store energy with a predetermined capacity.

[0037] The electrical storage device 500It is equipped with a power conditioner 510 on its output side. The power conditioner 510 is configured to include various power elements such as a DC / DC converter and an AC / DC converter. Direct current is supplied to the electrical device. 500 stored, and therefore the power is converted by the power conditioner 510 so that it is compatible with the AC system 200 meets the required specification.

[0038] The control device 600 It serves as a control unit for the hybrid power generation system 100 configured by including hardware formed by an electronic computing device, such as a computer, and a program on the hardware for carrying out the control procedure of the hybrid power generation system. 100The program is installed according to at least one embodiment of the present invention. For example, the program can be installed by reading a program stored in a predetermined storage medium using a hardware reading device, and the program and the storage medium containing the program also fall within the technical scope of the present invention.

[0039] Fig. 3 is a block diagram of the configuration, which functionally represents an internal configuration of the control device. 600 in Fig. 1 shows. The control device 600 inputs into the controller control 414 a deviation between an entered target rotational speed and a measured actual value of the rotational speed, which is determined by the flywheel 411 the rotary current generating device 400 arranged rotational speed detection sensor 412The system detects the deviation and outputs a control signal regarding the actuator opening degree, which is the control parameter corresponding to the deviation. This control signal is then input into the controller actuator. 416 The regulator actuator will 416 controlled, and a feedback control is implemented at the fuel injection pump. 415 of the engine 410 performed (see Fig. 2) This increases the rotational speed of the motor. 410 maintained at the target rotation speed and the output frequency of the motor 410 coupled generator 420 kept constant.

[0040] The control device 600 It also includes a renewable energy recording section. 610 , in order to record the amount of renewable energy supplied to the renewable energy power generation device 300 is supplied, and an output recording section 620the renewable energy power generation device 300 , to capture the output. The renewable energy capture section 610 records the amount of renewable energy supplied to the renewable energy power generation device 300 is supplied by means of a measurement value from the renewable energy measurement sensor. 320 Recorded. The output recording section 620 records the output of the renewable energy power generation device 300 , by taking a reading from the output reading sensor 330 recorded.

[0041] The presented embodiment describes a case in which the control device 600 both the renewable energy recording section 610 as well as the output recording section 620 It contains the control device. 600 However, only at least one of the renewable energy recording sections needs to be included. 610or the output recording section 620 included, as described above, in accordance with the renewable energy detection sensor 320 or the output capture sensor 330 .

[0042] The renewable energy generated by the capture section 610 for renewable energy, or the output recorded by the output recording section 620 The data is recorded and entered into a fluctuation determination section. 630 entered. The fluctuation determination section. 630 It monitors changes over time in renewable energy or output and determines that a fluctuation exists if the amount of change exceeds a predetermined value within a predetermined time period.

[0043] The control device 600 includes a correction value calculation section 640to calculate a correction value of the control parameter (actuator opening degree) based on a fluctuation amount of a case in which the fluctuation determination section 630 determines that fluctuations exist in renewable energy or output. The present system is equipped with a storage section. 650 for storing various types of information (such as engine specifications (displacement and nominal rotational speed)) 410 and a moment of inertia of the generator 420 the rotary power generating device 400 ) provided, which were prepared in advance. The correction value calculation section. 640 calculates a correction value with respect to the control parameter based on the operating state (output) of the rotary current generating device. 400 , which is from an operating status detection section 660 is recorded, along with the data in the storage section 650stored information.

[0044] The storage section 650 stores a map or calculation expression to determine the correction value based on the fluctuation amount of renewable energy recorded by the Renewable Energy Capture section. 610 is recorded, or the output of the renewable energy power generation device 300 , which are processed by the output recording section 620 is recorded, and the operating state (output) of the rotary power generating device 400 to obtain. The correction value calculation section. 640 appropriately reads the characteristic map or calculation expression, thereby determining the correction value based on the fluctuation amount of the renewable energy supplied by the renewable energy recording section. 610 is recorded, or the output of the renewable energy power generation device 300 , which is from the output recording section620 is recorded, and the operating state (output) of the rotary power generating device 400 is calculated.

[0045] The correction value calculation section 640 The calculated correction value is added as a forward signal to the control parameter on the feedback control circuit described above. In the presented embodiment, the correction value is added to the actuator opening degree, which is determined by the controller. 414 The output control parameter is then entered into the actuator of the controller, to which the correction value is added, and a forward control is performed using the correction value.

[0046] The correction value calculation section 640 The calculated correction value is applied to the control parameter via a damping process section. 670 added. The damping process section 670It performs a process of gradually damping the correction value over a predetermined period after the fluctuation in renewable energy has been determined, thereby configuring it so that forward control is limited by the correction value when renewable energy fluctuates.

[0047] The following describes a method for controlling the hybrid power generation system. 100 described with the configuration above. Fig. Figure 4 is a flowchart showing the steps of the control procedure of the hybrid power generation system. 100 as shown according to at least one embodiment of the present invention.

[0048] First, the fluctuation determination section monitors 630 the amount of renewable energy supplied to the renewable energy power generation device 300The system is fed in (step S1) and determines whether renewable energy fluctuations are present (step S2). The presence or absence of fluctuations is assessed based on whether the fluctuation amount exceeds the predetermined value within the predetermined time, as measured by the renewable energy detection sensor. 320 is recorded sequentially over time.

[0049] In step S2, the fluctuation determination section can be accessed. 630 determine whether it is the fluctuation in the output of the renewable energy power generation device 300 gives, by the output of the renewable energy power generation device 300 is monitored. In this case, the presence or absence of fluctuation is assessed based on whether the fluctuation amount exceeds the predetermined value within the predetermined time, as measured by the output sensor's reading. 330is recorded sequentially over time.

[0050] If it is the fluctuation in renewable energy (or the output of the renewable energy power generation device) 300 If (step S2: YES) the correction value calculation section is entered 640 the relevant fluctuation amount (step S3). (a) of Fig. Equation 5, which is described later, shows that a solar irradiance amount is reduced from R1 to R2 at time t1, and a fluctuation amount of this is ΔR. (b) of Fig. Figure 5 shows that the output of the renewable energy power generation device 300 at time t1, the value of E1 is reduced to E2, and a fluctuation amount of this is ΔE.

[0051] The operational status monitoring section then records data. 660 the operating state of the rotary power generating device 400(Step S4). The operating state is, for example, derived from the output (amount of power generation) of the rotary power generation device. 400 Estimated engine power. The operating condition can be determined by observing the boost pressure via a boost pressure sensor.

[0052] The correction value calculation section then calculates 640 The correction value is calculated based on the fluctuation amount ΔR (or ΔE) recorded in step S3 and the operating state recorded in step S4 (step S5). The relationship between the fluctuation amount ΔR (or ΔE), the operating state, and the correction value is determined using the memory section. 650 defined by a pre-stored characteristic map or the calculation expression. The correction value calculation section 640 extracts the characteristic map or the calculation expression from the memory section 650and calculates the correction value according to the fluctuation amount ΔR (or ΔE) recorded in step S3 and the operating state recorded in step S4.

[0053] The correction value calculated in this way goes through the damping process through the damping process section. 670 (Step S6) and is then, as in Fig. As shown in step 3, the forward component is added to the control parameter on the control circuit (step S7). Then the control device executes 600 a feedback control based on the control parameter, to which the forward component is thus added, thereby changing the frequency of the rotary current generating device. 400 is maintained at a target frequency (step S8).

[0054] Fig. Figure 5 shows diagrams illustrating the temporal transitions of renewable energy, the output of the renewable energy power generation device, and the operating state (output) or output frequency of the rotary power generation device. As a comparative example, it shows... Fig. 5 as (e) of Fig. 5 the temporal transition of the output frequency of the rotary current generating device in a case where the same feedback control is performed using the control parameter to which the correction value is not added as a forward component. (a) of Fig. Figure 5 shows a change over time in the amount of solar irradiance (solar energy), which is the renewable energy, and shows a state in which the amount of solar irradiance decreases from R1 to R2 at time t1, and the amount of fluctuation of this is ΔR. (b) of Fig. Figure 5 shows a change in the output of the renewable energy power generation device over time.300 and shows a state in which the output from E1 to E2 at time t1 is reduced to match that in (a) of Fig. to correspond to the 5 shown renewable energy, and the fluctuation amount of this is ΔE. (c) of Fig. Figure 5 shows a change in the load of the rotary power generating device over time. 400 There is no small time delay until the fluctuation in renewable energy (see (a) in Fig. 5) or the fluctuation in the output of the renewable energy power generation device 300 (see (b) in Fig. 5) as a load of the rotary power generating device 400 is transferred. Thus, (c) shows from Fig. 5 a state in which the load of the rotary power generating device 400 at time t2, the level of L1 is increased to L2 after time t1. (d) of Fig. Figure 5 shows a change in the output frequency of the rotary power generation device over time.400 in the present embodiment. (d) of Fig. Figure 5 shows, by means of a dashed line, the correction value, which is the feedback component added to the control parameter, and shows a state in which the correction value is increased to the predetermined value at time t1 when the fluctuation in the renewable energy or the output of the renewable energy power generation device 300 occurs, and then gradually through the damping process through the damping process section 670 is reduced. By adding such a correction value to the control parameter as a feedback component, the output frequency of the rotary current generating device is reduced. 400 a good subsequent output in terms of the target frequency.

[0055] During a period in which the feedback component has an effective value (up to the point at which the feedback component becomes zero due to the damping process), a gain in the feedback control (controller control) can be achieved. 414 ) temporarily reduced. This emphasizes the forward component added to the control parameter. In this way, it is possible to suppress the decrease in the rotational speed of the rotary power generation device more effectively. (a Fig. Figure 5 is a comparative example according to the conventional state of the art, and in this comparative example, the correction value is not added as a feedback component to the control parameter. Thus, in this comparative example, the occurrence of fluctuations in renewable energy or the output of the renewable energy power generation device is not affected. 300from time t2 behind time t1, and furthermore, the fluctuation width Δf of the output frequency is large relative to the target frequency, and the time required to converge to the target frequency is long. In contrast, the one in (d) of Fig. In embodiment 5, a tracking control to the target frequency is provided from time t1 before time t2, the fluctuation width Δf is small, and furthermore, the convergence to the target frequency is early.

[0056] Therefore, in the presented embodiment, the correction value is based on the fluctuation of renewable energy or the output of the renewable energy power generation device. 300 calculated and added as a forward component to the control parameter. In this way, it is possible to start the tracking control to the target frequency at a time earlier than time t2, at which the output of the rotary power generation device is reached.400 fluctuates, resulting in excellent responsiveness. This means that, in feedback control as in the comparison example, the follow-up control is initiated after the fluctuation in the renewable energy or the output of the power generation device. 300 for renewable energy, the output fluctuation of the rotary power generating device 400 affected, whereas in the present embodiment, forward control makes it possible to improve the stability of the target frequency.

[0057] Furthermore, the correction value, which is the forward component added to the control parameter, is based on the fluctuation amount of the renewable energy or the output of the renewable energy power generation device. 300 and the operating state of the rotary power generating device 400calculated, thereby reducing the fluctuation width Δf of the output frequency relative to the target frequency and also enabling early convergence to the target frequency.

[0058] Thus, in the presented embodiment, by developing control parameters for the output frequency relative to the target frequency, it is possible to implement output stabilization cost-effectively with fluctuating renewable energy without modifying the hardware. In particular, since the output stabilization is implemented in a control aspect, the capacity provided by the electrical storage device can be reduced. 500 , which are in the hybrid power generation system 100 The required power is correspondingly low. Therefore, it is possible to design the electrical storage device. 500 to reduce or eliminate it. This has the advantage of lowering the cost of the electrical device. 500, which contain an expensive lithium-ion battery or similar, can be significantly reduced. Industrial applicability

[0059] At least one embodiment of the present invention can be used for a hybrid power generation system comprising a renewable energy power generation device and a rotary power generation device connected to a common alternating current system, as well as a method for controlling the hybrid power generation system. Reference symbol list 100 hybrid power generation systems 200 AC system 300 Renewable energy power generation device 320 Renewable Energy Detection Sensor 330 Output detection sensor 400 Rotary Power Generating Device 410 engine 411 Flywheel 412 Rotational speed detection sensor 414 Rotation speed controller 415 Fuel injection pump 416 Regulator actuator 420 alternator 500 Electrical storage device 600 Control device 610 Renewable Energy Recording Section 620 Output recording section 630 Fluctuation Determination Section 640 Correction value calculation section 650 storage section 660 Operating status monitoring section 670 Damping process section

Claims

[1] A hybrid power generation system comprising: a renewable energy power generation device capable of generating electricity using renewable energy; a rotary power generating device connected to an alternating current system common to the renewable energy power generating device, wherein the rotary power generating device is capable of generating energy in such a way as to reduce output fluctuations of the renewable energy power generating device; and a control device for controlling the rotary current generating device, such that the rotational speed of the rotary current generating device reaches a target rotational speed, the hybrid power generation system includes the following: a fluctuation determination section to determine whether a fluctuation amount of renewable energy supplied to the renewable energy power generation device or an output of the renewable energy power generation device exceeds a predetermined value; and a correction value calculation section for calculating a correction value of the tax parameter based on the fluctuation amount, and wherein the control device controls the rotary power generating device on the basis of a control parameter obtained by adding the correction value calculated by the correction value calculation section as a forward component when the fluctuation determination section determines that the fluctuation amount of renewable energy supplied to the renewable energy power generating device or the output of the renewable energy power generating device exceeds the predetermined value. [2] The hybrid power generation system according to claim 1, wherein the control device performs feedback control of the control parameter based on a difference between the target rotational speed and an actual measured rotational speed of the rotary current generator. [3] The hybrid power generation system according to claim 2, wherein the control device temporarily reduces a gain when it performs feedback control on the control parameter when the fluctuation determination section determines that the fluctuation amount of renewable energy supplied to the renewable energy power generation device or the output of the renewable energy power generation device exceeds the predetermined value. [4] The hybrid power generation system according to any one of claims 1 to 3, further comprising: a memory section for storing reference data that defines a relationship between the fluctuation amount and the correction value for each operating state of the rotary current generating device; and an operating status monitoring section for recording the operating status of the rotary power generating device, wherein the correction value calculation section calculates the correction value of the control parameter based on the fluctuation amount, based on the reference data corresponding to the operating state captured by the operating state capture section. [5] The hybrid power generation system according to any one of claims 1 to 4, comprising an electrical storage device connected to the AC grid, such that the output fluctuation of the rotary power generation device is reduced. [6] The hybrid power generation system according to any one of claims 1 to 5, wherein the renewable energy is solar energy. [7] The hybrid power generation system according to any one of claims 1 to 5, wherein the renewable energy is wind energy. [8] The hybrid power generation system according to any one of claims 1 to 7, wherein the rotary power generating device includes a motor as an energy source, and where the control parameter is a drive amount of an actuator for adjusting a fuel injection amount of the engine. [9] A method for controlling a hybrid power generation system, comprising: a renewable energy power generation device capable of generating electricity using renewable energy; a rotary power generating device connected to an alternating current system common to the renewable energy power generating device, wherein the rotary power generating device is capable of generating power in such a way as to reduce output fluctuations of the renewable energy power generating device; and a control device for controlling the rotary current generating device such that a rotational speed of the rotary current generating device reaches a target rotational speed, wherein the control method comprises: a fluctuation determination step of determining whether a fluctuation amount of renewable energy supplied to the renewable energy power generation device or an output of the renewable energy power generation device exceeds a predetermined value; and a control step of controlling the rotary current generating device such that the rotational speed of the rotary current generating device reaches the target rotational speed, wherein, if the fluctuation determination section determines that the fluctuation amount of renewable energy supplied to the renewable energy power generating device or the output of the renewable energy power generating device exceeds the predetermined value, in the control step the rotary power generating device is controlled on the basis of a control parameter obtained by adding a correction value calculated on the basis of the fluctuation amount as a forward component.