Flywheel energy storage and flywheel phase modifier cooperative frequency support control method

Abstract

The invention belongs to the technical field of flywheel energy storage, and particularly discloses a flywheel energy storage and flywheel phase modifier cooperative frequency support control method, which comprises the following steps: if it is detected that power grid frequency fluctuation exceeds a preset range, preferentially triggering a flywheel phase modifier in an inertia response stage to provide instantaneous inertia support through rotation kinetic energy so as to slow down a power grid frequency falling speed; starting the flywheel energy storage system to perform high-frequency charging and discharging to smooth power grid frequency fluctuation; in the primary frequency modulation stage, the output power of the flywheel phase modifier and the flywheel energy storage system is dynamically and coordinately distributed based on the real-time power grid frequency and voltage deviation, and the power grid frequency is recovered and stabilized by taking the flywheel energy storage system as a main part and the flywheel phase modifier as an auxiliary part. According to the invention, cooperative frequency support control of flywheel energy storage and the flywheel phase modifier when a power grid breaks down suddenly is realized.

Description

Technical Field

[0001] The present application belongs to the technical field of flywheel energy storage, and more specifically, to a method for controlling flywheel energy storage and flywheel phase regulator coordinated frequency support. Background Art

[0002] In modern power systems, a high proportion of renewable energy is connected to the grid. Due to the strong volatility and randomness of new energy, it will lead to a lack of grid inertia and insufficient power support. Traditional grid frequency regulation mainly relies on the speed regulator and synchronizer of synchronous generator sets to adjust power output. It is difficult to respond flexibly and quickly to frequency changes, especially the rapid frequency fluctuations caused by sudden failures in the grid. The limitation of traditional frequency regulation is that it has a slow response speed and is difficult to provide sufficient regulation power in a short period of time.

[0003] At present, the means by which flywheel energy storage participates in auxiliary frequency regulation are mostly single flywheel devices assisting thermal power units or wind turbines in participating in grid frequency regulation. Flywheel energy storage and flywheel phase regulators can jointly participate in frequency support, which can give full play to their respective advantages and achieve coordinated frequency support. However, there is still a gap in the research on how to conduct coordinated frequency support control of flywheel energy storage and flywheel phase regulators. Summary of the invention

[0004] In view of the above-mentioned defects in the related technology, the present application provides a method for coordinated frequency support control of flywheel energy storage and flywheel phase regulator, aiming to solve the problem of coordinated frequency support control of flywheel energy storage and flywheel phase regulator.

[0005] In a first aspect, the present application provides a flywheel energy storage and flywheel phase regulator coordinated frequency support control method, comprising: If it is detected that the grid frequency fluctuation exceeds the preset range, the flywheel phase regulator is triggered first in the inertia response stage to provide instantaneous inertia support through rotational kinetic energy to slow down the speed of grid frequency decline, and the flywheel energy storage system is started for high-frequency charging and discharging to smooth the grid frequency fluctuation; In the primary frequency regulation stage, the output power of the flywheel phase condenser and the flywheel energy storage system is dynamically coordinated and allocated based on the real-time grid frequency and voltage deviation, with the flywheel energy storage system as the main component and the flywheel phase condenser as the auxiliary component to restore and stabilize the grid frequency.

[0006] In a second aspect, the present application also provides a flywheel energy storage and flywheel phase regulator coordinated frequency support control system, comprising: The first control module is used to, if it is detected that the grid frequency fluctuation exceeds a preset range, preferentially trigger the flywheel phase regulator to provide instantaneous inertia support through rotational kinetic energy to slow down the speed of grid frequency decline in the inertia response phase, and start the flywheel energy storage system to perform high-frequency charging and discharging to smooth the grid frequency fluctuation; The second control module is used to dynamically coordinate and allocate the output power of the flywheel phase regulator and the flywheel energy storage system based on the real-time grid frequency and voltage deviation during the primary frequency regulation stage, mainly using the flywheel energy storage system and supplemented by the flywheel phase regulator to restore and stabilize the grid frequency.

[0007] In a third aspect, the present application also provides an electronic device, comprising: at least one memory for storing programs; and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the first aspect or any possible implementation of the first aspect.

[0008] In a fourth aspect, the present application also provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.

[0009] In a fifth aspect, the present application further provides a computer program product, which, when executed on a processor, enables the processor to execute the method described in the first aspect or any possible implementation manner of the first aspect.

[0010] The flywheel energy storage and flywheel phase regulator coordinated frequency support control method provided in the present application, when a sudden grid failure causes the grid frequency fluctuation to exceed the limit, in the inertia response stage, the flywheel phase regulator is preferentially triggered to provide instantaneous inertia support through rotational kinetic energy to prevent the grid frequency from falling rapidly, and then the flywheel energy storage system is started to charge and discharge rapidly to smooth the grid frequency fluctuation; in the primary frequency regulation stage, two-way power regulation is provided in a short time through the coordinated support of the two to restore and stabilize the grid frequency, thereby realizing rapid power support and precise control in the event of a sudden grid failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in this application or related technologies, the following will describe the appended materials required in the embodiments or related technical descriptions. Figure 1 To make a brief introduction, it is obvious that the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0012] Figure 1 It is a structural schematic diagram of a hybrid system including flywheel energy storage and flywheel phase regulator provided in an embodiment of the present application; Figure 2 It is one of the flow charts of the flywheel energy storage and flywheel phase regulator coordinated frequency support control method provided in the embodiment of the present application; Figure 3This is the second flow chart of the flywheel energy storage and flywheel phase regulator coordinated frequency support control method provided in the embodiment of the present application; Figure 4 It is a schematic diagram of the principle of controlling the output power of a flywheel energy storage system by a machine-side converter provided in an embodiment of the present application; Figure 5 It is a schematic diagram of the principle of controlling the DC bus voltage by the grid-side converter provided in an embodiment of the present application; Figure 6 This is a circuit structure diagram of a flywheel energy storage system and a flywheel phase regulator hybridly connected to a photovoltaic station provided in an embodiment of the present application; Figure 7 This is a schematic diagram of the effect of flywheel energy storage and flywheel phase regulator coordinated frequency support provided by an embodiment of the present application; Figure 8 It is a structural schematic diagram of a flywheel energy storage and flywheel phase regulator coordinated frequency support control system provided in an embodiment of the present application; Fig. 9 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0013] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0014] Figure 1 is a structural schematic diagram of a hybrid system including flywheel energy storage and flywheel phase regulator provided in an embodiment of the present application, such as Figure 1 As shown in the figure, the hybrid system contains a flywheel energy storage system with a single unit of 1.25MW and a flywheel phase regulator with a single unit of 5MW / 6MVA. The flywheel energy storage system outputs 690V AC voltage through the AC-DC-AC converter and is connected to the low-voltage side converter. The converter topology is a reverse two-level voltage source converter (VSC), and the trigger pulse is generated by sinusoidal pulse width modulation (SVPWM). The output voltage level of the flywheel phase regulator is 10.5 kV, which is connected to the 35kV bus after being stepped up by the low-voltage transformer, and then connected to the grid through the high-voltage bus after being stepped up to 220kV.

[0015] For flywheel energy storage systems, the kinetic energy stored in the high-speed flywheel is its moment of inertia (kg / m2) and angular velocity The function of the square of (rad / s) can be expressed as:

[0016] Among them, the moment of inertia of the flywheel Depends on the flywheel mass and the geometry of the flywheel body; to ensure safe operation, the angular velocity of the flywheel Limited to a minimum and maximum value Therefore, the available energy of the high-speed flywheel energy storage system Specifically, it can be expressed as:

[0017] The flywheel's state of energy (SOE) defines the amount of kinetic energy stored / released during its charge and discharge. During charge and discharge operations, the SOE increases or decreases depending on the direction of the flywheel's power. The flywheel's state of energy at time t is Specifically, it can be expressed as:

[0018] in, is the running time since the flywheel started, is the flywheel power, is the operating efficiency of the flywheel energy storage system, the constant It is the friction coefficient when the rotor rotates at high speed.

[0019] Flywheel phase regulator stores energy through the built-in flywheel energy storage device and releases energy when needed to adjust the frequency and power of the power grid. The phase regulator is mainly used to adjust the phase difference between voltage and current in the AC circuit.

[0020] Figure 2 This is one of the flow charts of the flywheel energy storage and flywheel phase regulator coordinated frequency support control method provided in the embodiment of the present application. Figure 3 This is the second flow chart of the flywheel energy storage and flywheel phase regulator coordinated frequency support control method provided in the embodiment of the present application. Figure 2 and Figure 3 The technical solution of the embodiment of the present application is introduced in detail.

[0021] like Figure 2 As shown, the execution subject of the method is a control system for flywheel energy storage and flywheel phase regulator coordinated frequency support, and the method includes at least the following steps: S201, when it is detected that the grid frequency fluctuation exceeds the preset range, in the inertia response stage, the flywheel phase regulator is preferentially triggered to provide instantaneous inertia support through rotational kinetic energy to slow down the speed of grid frequency drop, and the flywheel energy storage system is started to perform high-frequency charging and discharging to smooth the grid frequency fluctuation; S202. In the primary frequency regulation stage, the output power of the flywheel phase regulator and the flywheel energy storage system is dynamically coordinated and allocated based on the real-time grid frequency and voltage deviation, with the flywheel energy storage system as the main component and the flywheel phase regulator as the auxiliary component to restore and stabilize the grid frequency.

[0022] In the embodiment of the present application, when a sudden grid failure causes the grid frequency to fluctuate beyond a limit, in the inertia response stage, the flywheel phase regulator is preferentially triggered to provide instantaneous inertia support through rotational kinetic energy to prevent a rapid drop in the grid frequency, and then the flywheel energy storage system is started to charge and discharge rapidly to smooth the grid frequency fluctuation; in the primary frequency regulation stage, the coordinated support of the two is used to provide two-way power regulation in a short time to restore and stabilize the grid frequency, thereby achieving rapid power support and precise control in the event of a sudden grid failure.

[0023] Combination Figure 3 When the grid frequency fluctuates beyond the preset range (grid failure or load mutation, etc.), the flywheel energy storage system and the flywheel phase regulator will collaboratively support the grid frequency in the two stages of inertia response and primary frequency regulation.

[0024] For S201, the inertia response stage is the first time response of the power system to the frequency change by relying on the rotational inertia of the synchronous generator when the power system is subjected to power disturbance (load mutation or fault, etc.).

[0025] As a device based on a synchronous generator, the flywheel phase regulator stores mechanical energy through a built-in high-speed rotating flywheel. Its main function is to provide reactive power support and inertia response. When the grid frequency fluctuates or the voltage drops, the rotational kinetic energy of the rotating flywheel built into the flywheel phase regulator can be quickly converted into electrical power through electromagnetic coupling, and the instantaneous reactive power can be quickly provided through the rotational inertia to help the grid restore the stability of frequency and voltage; at the same time, it can also improve the short-circuit capacity of the grid and enhance the fault ride-through capability of the system. The reactive power output of the flywheel phase regulator can be achieved by adjusting the excitation current.

[0026] Therefore, in a hybrid system containing a flywheel energy storage system and a flywheel phase regulator, if it is detected that the grid frequency fluctuation exceeds a preset range, in the inertia response stage when the grid frequency is stable, the coordinated frequency support of the hybrid system is achieved through a priority control strategy, and the flywheel phase regulator is preferentially triggered to provide instantaneous inertia support through rotational kinetic energy to slow down the speed of grid frequency decline, and then the flywheel energy storage system is started for high-frequency charging and discharging to smooth the grid frequency fluctuation, thereby achieving coordinated optimization of the flywheel energy storage and flywheel phase regulator in response speed and energy usage.

[0027] For S202, the primary frequency regulation stage is the process of automatically adjusting the generator output through the speed governor to restore power balance and frequency stability when the grid frequency fluctuation exceeds the preset range. It is the second stage of grid frequency regulation.

[0028] The flywheel energy storage system uses an integrated motor / generator to achieve rapid storage and release of electrical energy. Its frequency regulation characteristics mainly include rapid active power regulation, two-way regulation capability, and efficient and flexible response. The flywheel energy storage system can quickly release or absorb energy in milliseconds to cope with frequency fluctuations; it can absorb excess energy when the frequency is too high, and release energy to support the frequency when the frequency is too low; it is suitable for transient adjustment of frequency fluctuations and has good dynamic characteristics.

[0029] Therefore, in a hybrid system containing a flywheel energy storage system and a flywheel phase regulator, during the primary frequency regulation stage when the grid frequency is stable, the output power of the flywheel phase regulator and the flywheel energy storage system is dynamically coordinated and allocated based on the real-time grid frequency and voltage deviation, and the grid frequency is restored and stabilized with the flywheel energy storage system as the main component and the flywheel phase regulator as the auxiliary component.

[0030] In some embodiments, in S102, the output power of the flywheel phase regulator and the flywheel energy storage system is dynamically coordinated and allocated based on the real-time grid frequency and voltage deviation, specifically including: Dynamically determine the active power reference value based on the real-time grid frequency and send it to the flywheel energy storage system, so that the flywheel energy storage system outputs active power based on the active power reference value to adjust the grid frequency; The reactive power reference value is dynamically determined based on the real-time voltage deviation and sent to the flywheel phase regulator, so that the flywheel phase regulator outputs reactive power based on the reactive power reference value to adjust the grid voltage.

[0031] Specifically, the coordinated frequency support control of the flywheel energy storage system and the flywheel phase condenser adopts an active-reactive coordinated control strategy. The flywheel energy storage system quickly releases or absorbs active power according to the active power reference value to adjust the grid frequency; the flywheel phase condenser quickly adjusts the reactive power according to the reactive power reference value to adjust the grid voltage.

[0032] The active power droop control and reactive power droop control equations are as follows:

[0033]

[0034] in, and is the active power output and reactive power output of the hybrid flywheel array; and are active power reference value and reactive power reference value; and They are active power droop coefficient and reactive power droop coefficient respectively; is the output angular frequency; is the rated angular frequency of the power grid, i.e. 2×pi×50; and are the voltage reference value and the actual voltage value.

[0035] The SOE of the flywheel energy storage system can be specifically expressed as:

[0036] in, , , are the current, maximum and minimum angular velocities of the i-th flywheel in the flywheel energy storage system respectively.

[0037] When the grid frequency exceeds the specified range, the upper control system calculates the output power of the flywheel energy storage system for primary frequency regulation according to the droop control principle. The output power can be specifically expressed as:

[0038] in, It is the total power output value of the flywheel energy storage system in the primary frequency regulation stage; Is the basic power output value, provided by the main frequency regulating unit; It is the additional power output value provided by the flywheel energy storage system.

[0039] The additional power output equation of the flywheel energy storage system can be specifically expressed as:

[0040] in, is the frequency adjustment coefficient, The unit regulation power of the flywheel energy storage system is is the grid frequency deviation value.

[0041] When the flywheel energy storage system participates in frequency regulation and needs to be charged, its SOE value is less than 0.85 and is considered available; when it needs to be discharged, its SOE value is greater than 0.15 and is considered available; that is, the frequency regulation coefficient Specifically, it can be expressed as:

[0042] In addition, the coordinated frequency support control of the flywheel energy storage system and the flywheel phase condenser also adopts a hierarchical control strategy, which includes upper-level control and lower-level control. Upper-level control: the control system dynamically determines the active power reference value based on the real-time grid frequency, and dynamically determines the reactive power reference value based on the real-time voltage deviation, and sends the reference values ​​to the flywheel energy storage system and the flywheel phase condenser respectively through relevant instructions; Lower-level control: after receiving the upper-level instructions, the flywheel energy storage system and the flywheel phase condenser output active power and reactive power respectively according to the power reference value.

[0043] Furthermore, the flywheel phase regulator in the hybrid system realizes coordinated frequency support control with the flywheel energy storage system by participating in the power loop of the flywheel energy storage system.

[0044] Figure 4 Schematic diagram of the principle of the machine-side converter controlling the output power of the flywheel energy storage system provided in the embodiment of the present application, such as Figure 4 As shown, for the flywheel energy storage system, the machine-side converter controls the output power of the flywheel energy storage system, and adopts a power and current dual closed-loop control method, in which the power loop is the control outer loop and the current loop is the control inner loop.

[0045] The drive motor of the flywheel energy storage is a permanent magnet synchronous motor. The goal of the vector control of the machine-side converter is to achieve the regulation of active power and reactive power on the stator side. The mathematical model of the permanent magnet synchronous motor in the stator three-phase stationary coordinate system and the voltage equation can be specifically expressed as:

[0046] in, , , are the instantaneous values ​​of the three-phase stator voltages, is the stator winding resistance, , , are the instantaneous values ​​of the three-phase current of the stator, , , They are the instantaneous values ​​of the stator three-phase winding flux.

[0047] The magnetic flux equation can be specifically expressed as:

[0048] in, is the permanent magnet flux amplitude, , , are the flux generated by the permanent magnet in the stator three-phase winding, It is the electrical angle of the rotor direct axis relative to the stator a-phase axis.

[0049] By adopting rotor flux orientation, the permanent magnet generates a rotor flux with a constant amplitude. The flux equation can be specifically expressed as:

[0050] in, , They are the d-axis component and q-axis component of the permanent magnet flux respectively.

[0051] Based on the mathematical model of permanent magnet synchronous motor, ignoring the stator resistance, the electromagnetic power output on the stator side can be specifically expressed as:

[0052] in, is the electromagnetic power output by the stator, is the rotor angular speed, is the q-axis component of the stator current.

[0053] It can be seen that the active power output on the stator side of the permanent magnet synchronous motor is only proportional to the q-axis component of the stator current. The active power generated by the permanent magnet synchronous motor can be controlled by controlling the q-axis component of the stator current. The d-axis current reference signal is set to 0 to ensure the regulation of active power within the limited current control capability.

[0054] The control equation of the machine-side converter can be specifically expressed as:

[0055] in, , are the d-axis component and q-axis component of the stator voltage respectively, is the stator winding resistance, , are the d-axis component and q-axis component of the stator winding current, respectively. , are the d-axis inductance and q-axis inductance of the stator winding respectively.

[0056] The mathematical model of the grid-side converter in the synchronous rotating dq coordinate system can be specifically expressed as:

[0057] in, , are the d-axis component and q-axis component of the grid voltage respectively, , are the d-axis component and q-axis component of the AC side voltage of the grid-side converter, , are the d-axis and q-axis components of the grid-side current, , are the line resistance and the reactor inductance respectively, is the grid angular frequency, is the DC bus capacitance, is the DC side load current, and are the d-axis and q-axis components of the switching function respectively.

[0058] The grid-side converter is oriented based on the d-axis grid voltage, and the conditions that meet the conditions can be specifically expressed as:

[0059] in, is the peak value of the phase voltage of the power grid.

[0060] At this time, the mathematical model of the grid-side converter can be changed to:

[0061] From this, the AC output voltage equation of the grid-side converter in the form of dq components based on the d-axis grid voltage orientation can be derived as follows:

[0062] In order to eliminate the dq axis current coupling, the disturbance control quantity of the grid voltage and the control static error, a proportional-integral link is introduced and the current inner loop is designed to meet the following requirements:

[0063] in, , They are the d-axis component and q-axis component of the output voltage of the inner current loop, , are the current reference values ​​of the d-axis and q-axis respectively, , They are the proportional coefficient and integral coefficient of the inner current loop respectively.

[0064] From this, the output voltage reference value equation of the grid-side converter can be obtained, which can be specifically expressed as:

[0065] in, , They are respectively the d-axis component reference value and the q-axis component reference value of the grid-side converter output voltage.

[0066] The control system gives the energy reference value and speed reference value required by the flywheel energy storage system. In the power loop controlled by the generator-side converter, the speed of the flywheel phase regulator is introduced for coordinated support control. The corresponding relationship can be specifically expressed as:

[0067]

[0068] in, The speed reference value of the flywheel energy storage system given by the energy management system, is the actual speed of the flywheel condenser, is the actual speed reference value of the flywheel energy storage system; is the actual output power of the flywheel energy storage system, is the speed-power proportional coefficient.

[0069] Combined with the speed feedback signal of the flywheel condenser, the q-axis reference current signal of the machine-side converter can be specifically expressed as:

[0070] in, is the q-axis reference current signal value of the machine-side converter, is the active power reference value of the flywheel energy storage system given by the control system, is the speed-to-power ratio coefficient, is the speed reference value of the flywheel energy storage system after the flywheel condenser is involved, For the integration phase, and They are the integral coefficient and proportional coefficient of the inner current loop respectively.

[0071] Figure 5 is a schematic diagram of the principle of controlling the DC bus voltage by the grid-side converter provided in an embodiment of the present application, such as Figure 5 As shown, the grid-side converter controls the DC bus voltage by adopting a voltage and current dual closed-loop control method, where the voltage loop is the outer control loop and the current loop is the inner control loop.

[0072] The embodiment of the present application provides a method for coordinated frequency support control of flywheel energy storage and flywheel phase regulator. When a rapid fluctuation of the power grid frequency is detected, the flywheel phase regulator first provides instantaneous inertia support through its rotational kinetic energy to prevent a rapid drop in the power grid frequency, and the flywheel energy storage system then enters a working state to rapidly adjust the output power to smooth the frequency fluctuation. During power regulation, the flywheel energy storage and the flywheel phase regulator's own characteristics are combined to achieve a dynamic coordinated allocation of the output power of the flywheel phase regulator and the flywheel energy storage system through a hierarchical control strategy, an active-reactive coordinated control strategy, etc. In terms of event-based coordinated control, when a rapid drop in the power grid frequency is detected, an event trigger mechanism is initiated to combine the inertia support of the flywheel phase regulator with the rapid regulation of the flywheel energy storage to achieve more precise frequency regulation control.

[0073] Furthermore, the effect of the technical solution provided in the embodiments of the present application was verified. Figure 6 : is a circuit structure diagram of a flywheel energy storage system and a flywheel phase regulator hybridly connected to a photovoltaic station provided in an embodiment of the present application, such as Figure 6 As shown, when exploring the supporting effect of flywheel energy storage and flywheel phase regulator on frequency, the infinite grid model is not used, and the flywheel energy storage and flywheel phase regulator are connected together with the photovoltaic station.

[0074] Figure 7 Schematic diagram of the effect of flywheel energy storage and flywheel phase regulator coordinated frequency support provided by the embodiment of the present application, such as Figure 7As shown in the figure, 5s after the system is running stably is used as the timing zero point, and 0.2s after the zero point is set, a three-phase grounding fault is imposed on the transmission line near the generator 2 side. The flywheel energy storage system is only put into operation for the first time, and the flywheel energy storage and flywheel phase regulator are put into operation for the second time. The coordinated frequency support effect of the hybrid system is better than that of the single flywheel energy storage system.

[0075] The flywheel energy storage and flywheel phase regulator coordinated frequency support control system provided in the present application is described below. The flywheel energy storage and flywheel phase regulator coordinated frequency support control system described below and the flywheel energy storage and flywheel phase regulator coordinated frequency support control method described above can be referenced to each other.

[0076] Figure 8 is a structural diagram of a flywheel energy storage and flywheel phase regulator coordinated frequency support control system provided in an embodiment of the present application, such as Figure 8 As shown, the system at least includes: The first control module 801 is used to, if it is detected that the grid frequency fluctuation exceeds a preset range, preferentially trigger the flywheel phase regulator to provide instantaneous inertia support through rotational kinetic energy to slow down the grid frequency drop speed in the inertia response stage, and start the flywheel energy storage system to perform high-frequency charging and discharging to smooth the grid frequency fluctuation; The second control module 802 is used to dynamically coordinate and allocate the output power of the flywheel phase regulator and the flywheel energy storage system based on the real-time grid frequency and voltage deviation during the primary frequency regulation stage, mainly using the flywheel energy storage system and supplemented by the flywheel phase regulator to restore and stabilize the grid frequency.

[0077] In some embodiments, the flywheel phase regulator achieves coordinated frequency support control with the flywheel energy storage system by participating in the power loop of the flywheel energy storage system.

[0078] In some embodiments, the power ring satisfies:

[0079]

[0080] in, is the speed reference value of the flywheel energy storage system given by the control system, is the actual speed of the flywheel condenser, is the speed reference value of the flywheel energy storage system after the flywheel condenser is involved, is the actual output power of the flywheel energy storage system, is the speed-to-power ratio coefficient.

[0081] In some embodiments, the output power of the flywheel energy storage system is controlled by: The power-current dual closed-loop control method is adopted through the machine-side converter, with the power loop as the outer control loop and the current loop as the inner control loop, to control the output power of the flywheel energy storage system; The DC bus voltage is controlled by adopting a voltage-current dual closed-loop control method through the grid-side converter, with the voltage loop as the control outer loop and the current loop as the control inner loop.

[0082] In some embodiments, the second control module 802 is specifically used to: Dynamically determine an active power reference value based on the real-time grid frequency and send it to the flywheel energy storage system, so that the flywheel energy storage system outputs active power based on the active power reference value to adjust the grid frequency; The reactive power reference value is dynamically determined based on the real-time voltage deviation and sent to the flywheel phase regulator, so that the flywheel phase regulator outputs reactive power based on the reactive power reference value to adjust the grid voltage.

[0083] In some embodiments, the output power value of the flywheel energy storage system in the primary frequency modulation stage satisfies:

[0084]

[0085] in, is the total power output of the flywheel energy storage system in a frequency regulation stage, is the basic power output value, is the additional power output value, is the frequency adjustment coefficient, The unit regulation power of the flywheel energy storage system is is the grid frequency deviation value.

[0086] In some embodiments, the flywheel energy storage system outputs active power based on the active power reference value by controlling the q-axis reference current signal of the machine-side converter, and the q-axis reference current signal satisfies:

[0087] in, is the q-axis reference current signal value of the machine-side converter, is the active power reference value of the flywheel energy storage system given by the control system, is the speed-to-power ratio coefficient, is the speed reference value of the flywheel energy storage system after the flywheel condenser is involved, For the integration phase, and They are the integral coefficient and proportional coefficient of the inner current loop respectively.

[0088] It can be understood that the detailed functional implementation of each of the above-mentioned units / modules can be found in the introduction of the aforementioned method embodiment, and will not be repeated here.

[0089] It should be understood that the above-mentioned device is used to execute the method in the above-mentioned embodiment. The implementation principle and technical effect of the corresponding program module in the device are similar to those described in the above-mentioned method. The working process of the device can refer to the corresponding process in the above-mentioned method, which will not be repeated here.

[0090] Based on the method in the above embodiment, an embodiment of the present application provides an electronic device. The device may include: at least one memory for storing programs and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the above embodiment.

[0091] Fig. 9 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application, such as Fig. 9 As shown, the electronic device may include: a processor (Processor) 901, a communication interface (Communications Interface) 902, a memory (Memory) 903 and a communication bus 904, wherein the processor 901, the communication interface 902, and the memory 903 communicate with each other through the communication bus 904. The processor 901 may call the software instructions in the memory 903 to execute the method described in the above embodiment.

[0092] In addition, the logic instructions in the above-mentioned memory 903 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application.

[0093] Based on the method in the above embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method in the above embodiment.

[0094] Based on the method in the above embodiment, an embodiment of the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method in the above embodiment.

[0095] It is understandable that the processor in the embodiment of the present application may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. The general-purpose processor may be a microprocessor or any conventional processor.

[0096] The method steps in the embodiments of the present application can be implemented by hardware or by a processor executing software instructions. The software instructions can be composed of corresponding software modules, and the software modules can be stored in random access memory (RAM), flash memory, read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), registers, hard disks, mobile hard disks, CD-ROMs, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an ASIC.

[0097] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted through the computer-readable storage medium. The computer instructions may be transmitted from a website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

[0098] It should be understood that the various numerical numbers involved in the embodiments of the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application.

[0099] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A flywheel energy storage and flywheel phase regulator coordinated frequency support control method, characterized in that: A control system applied to flywheel energy storage and flywheel phase regulator coordinated frequency support, the method comprising: If it is detected that the grid frequency fluctuation exceeds the preset range, the flywheel phase regulator is triggered first in the inertia response stage to provide instantaneous inertia support through rotational kinetic energy to slow down the speed of grid frequency decline, and the flywheel energy storage system is started for high-frequency charging and discharging to smooth the grid frequency fluctuation; In the primary frequency regulation stage, the output power of the flywheel phase regulator and the flywheel energy storage system is dynamically coordinated and allocated based on the real-time grid frequency and voltage deviation, with the flywheel energy storage system as the main component and the flywheel phase regulator as the auxiliary component to restore and stabilize the grid frequency.

2. The flywheel energy storage and flywheel phase regulator coordinated frequency support control method according to claim 1 is characterized in that: The flywheel phase regulator realizes coordinated frequency support control with the flywheel energy storage system by participating in the power loop of the flywheel energy storage system.

3. The flywheel energy storage and flywheel phase regulator coordinated frequency support control method according to claim 2, characterized in that: The power ring satisfies: in, is the speed reference value of the flywheel energy storage system given by the control system, is the actual speed of the flywheel condenser, is the speed reference value of the flywheel energy storage system after the flywheel condenser is involved, is the actual output power of the flywheel energy storage system, is the speed-to-power ratio coefficient.

4. The flywheel energy storage and flywheel phase regulator coordinated frequency support control method according to any one of claims 1 to 3, characterized in that: The output power of the flywheel energy storage system is controlled by: The output power of the flywheel energy storage system is controlled by adopting a power-current dual closed-loop control method through the machine-side converter, with the power loop as the outer control loop and the current loop as the inner control loop; The DC bus voltage is controlled by adopting a voltage-current dual closed-loop control method through the grid-side converter, with the voltage loop as the control outer loop and the current loop as the control inner loop.

5. The flywheel energy storage and flywheel phase regulator coordinated frequency support control method according to claim 1, characterized in that: The method of dynamically coordinating and allocating the output power of the flywheel phase regulator and the flywheel energy storage system based on the real-time grid frequency and voltage deviation includes: Dynamically determine an active power reference value based on the real-time grid frequency and send it to the flywheel energy storage system, so that the flywheel energy storage system outputs active power based on the active power reference value to adjust the grid frequency; The reactive power reference value is dynamically determined based on the real-time voltage deviation and sent to the flywheel phase regulator, so that the flywheel phase regulator outputs reactive power based on the reactive power reference value to adjust the grid voltage.

6. The flywheel energy storage and flywheel phase regulator coordinated frequency support control method according to claim 5, characterized in that: The output power value of the flywheel energy storage system in the primary frequency modulation stage satisfies: in, is the total power output value of the flywheel energy storage system in a frequency modulation stage, is the basic power output value, is the additional power output value, is the frequency adjustment coefficient, is the unit regulation power of the flywheel energy storage system, is the grid frequency deviation value.

7. The flywheel energy storage and flywheel phase regulator coordinated frequency support control method according to claim 5, characterized in that: The flywheel energy storage system outputs active power based on the active power reference value by controlling the q-axis reference current signal of the machine-side converter, and the q-axis reference current signal satisfies: in, is the q-axis reference current signal value, is the active power reference value of the flywheel energy storage system given by the control system, is the speed-to-power ratio coefficient, is the speed reference value of the flywheel energy storage system after the flywheel condenser is involved, For the integration phase, and They are the integral coefficient and proportional coefficient of the inner current loop respectively.

8. A flywheel energy storage and flywheel phase regulator coordinated frequency support control system, characterized in that: include: The first control module is used to, if it is detected that the grid frequency fluctuation exceeds a preset range, preferentially trigger the flywheel phase regulator to provide instantaneous inertia support through rotational kinetic energy to slow down the speed of grid frequency decline in the inertia response phase, and start the flywheel energy storage system to perform high-frequency charging and discharging to smooth the grid frequency fluctuation; The second control module is used to dynamically coordinate and allocate the output power of the flywheel phase regulator and the flywheel energy storage system based on the real-time grid frequency and voltage deviation during the primary frequency regulation stage, so as to restore and stabilize the grid frequency with the flywheel energy storage system as the main component and the flywheel phase regulator as the auxiliary component.

9. The flywheel energy storage and flywheel phase regulator coordinated frequency support control system according to claim 8, characterized in that: The flywheel phase regulator realizes coordinated frequency support control with the flywheel energy storage system by participating in the power loop of the flywheel energy storage system.

10. The flywheel energy storage and flywheel phase regulator coordinated frequency support control system according to claim 9, characterized in that: The power ring satisfies: in, is the speed reference value of the flywheel energy storage system given by the control system, is the actual speed of the flywheel condenser, is the speed reference value of the flywheel energy storage system after the flywheel condenser is involved, is the actual output power of the flywheel energy storage system, is the speed-to-power ratio coefficient.

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