Simulation control method and system based on super capacitor energy storage inertia support

Abstract

The invention discloses an analog control method and system based on super capacitor energy storage inertia support. The method comprises the following steps: simulating a selected new energy energy storage micro-grid topology; constructing a virtual synchronous machine according to the synchronous machine rotor motion equation and the super capacitor power dynamic equation; designing a corresponding inertia-damping-reactance control loop according to the virtual synchronous machine, and configuring the super capacitor under a preset condition based on the simulated inertia parameter, the frequency change range and the voltage change range determined from the control loop; the configured super capacitor is used as an energy storage support, and inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine are simulated according to an inertia-damping-reactance control loop; obtaining a target power reference value of the super capacitor in response to the inertia characteristic, the damping characteristic and the reactance characteristic; performing analog control on the output power of the super capacitor according to the target power reference value; the characteristics of the synchronous machine can be simulated through reasonable configuration, and the power grid stability is comprehensively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power grid control, and in particular to an analog control method and system based on supercapacitor energy storage inertia support. Background Art

[0002] In new energy storage microgrids, due to the intermittency and uncertainty of renewable energy sources such as solar and wind power, the stability and response speed of the system become key issues.

[0003] As a high-performance energy storage element, supercapacitors have the characteristics of fast charging and discharging and high power density. However, how to effectively configure and utilize supercapacitors to maximize their role in new energy storage microgrids is a technical challenge.

[0004] In practical applications, it is necessary to perform simulated control on the new energy storage microgrid that introduces supercapacitors. However, the existing simulated control methods are subject to the configuration defects of supercapacitors, resulting in poor inertia simulation effects. Ultimately, the results of the simulated control cannot effectively leverage the energy storage advantages of supercapacitors, and thus cannot achieve effective control of the characteristics of new energy grid units in the actual control process.

[0005] It can be seen that how to reasonably configure supercapacitors to improve the analog control effect has become a technical problem that needs to be urgently solved by those skilled in the art. Summary of the invention

[0006] The present invention provides a simulation control method based on supercapacitor energy storage inertia support to solve how to reasonably configure supercapacitors and effectively simulate the characteristics of synchronous machines, so as to optimize the control strategy of virtual synchronous machines and improve the accuracy of power grid system characteristic analysis.

[0007] In order to solve the above technical problems, an embodiment of the present invention provides an analog control method based on supercapacitor energy storage inertia support, comprising:

[0008] Simulate the selected target new energy storage microgrid topology;

[0009] According to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation, a virtual synchronous machine in the simulation result corresponding to the target new energy storage microgrid topology is constructed;

[0010] According to the virtual synchronous machine, a corresponding inertia-damping-reactance control loop is designed, and under preset conditions, based on simulated inertia parameters, frequency variation range, and voltage variation range determined from the inertia-damping-reactance control loop, a supercapacitor is configured in a simulation result corresponding to the target new energy storage microgrid topology to obtain a new energy storage microgrid simulated topology structure;

[0011] When running the simulated topology structure of the new energy storage microgrid, the configured supercapacitor is used as the energy storage support, and the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine are simulated according to the inertia-damping-reactance control loop;

[0012] acquiring a target power reference value of the supercapacitor in response to the inertia characteristic, the damping characteristic, and the reactance characteristic;

[0013] The output power of the supercapacitor is analog-controlled according to the target power reference value.

[0014] Further, constructing a virtual synchronous machine in the simulation result corresponding to the target new energy storage microgrid topology includes:

[0015] The synchronous machine rotor motion equation is expressed by the following formula:

[0016]

[0017] Where H is the inertia time constant of the synchronous machine, in S; D is the damping coefficient of the synchronous machine; f0, f and f g They are the synchronous machine rotor rated frequency, rotor instantaneous frequency and main grid frequency, in Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the synchronous machine when the rotor speed changes, respectively, in pu;

[0018] The supercapacitor power dynamic equation is expressed by the following formula:

[0019]

[0020] Among them, C sc is the capacitance value of the supercapacitor, in F; u sc is the overcapacity voltage, in V; S0 is the rated power of the inverter of the new energy power generation system, in VA; ΔP2 is the overcapacity exchange power, in pu;

[0021] The synchronous machine rotor motion equation and the supercapacitor power dynamic equation are combined to construct the virtual synchronous machine:

[0022] ΔP1=ΔP2.

[0023] Furthermore, when running the new energy storage microgrid simulation topology structure, the method further includes:

[0024] Constructing a small signal model of the photovoltaic power generation system in the inertia-damping-reactance control loop;

[0025] Analyzing the photovoltaic grid-connected system of the new energy storage microgrid simulated topology structure in a first operating state according to the root locus method, wherein the first operating state is determined by the simulation parameters of the inertia-damping-reactance control loop;

[0026] The simulation parameters are optimized according to the analysis results to obtain the optimized inertia characteristics, the damping characteristics and the reactance characteristics.

[0027] Furthermore, the target new energy storage microgrid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacitance control interface that match the supercapacitor.

[0028] Further, the analog control of the output power of the supercapacitor according to the target power reference value includes:

[0029] coupling the operating voltage of the supercapacitor with the main grid frequency;

[0030] In response to the coupling characteristic, the real-time output power of the super capacitor is dynamically adjusted based on the target power reference value.

[0031] Another embodiment of the present invention provides an analog control system based on supercapacitor energy storage inertia support, comprising:

[0032] The grid simulation module is used to simulate the selected target new energy storage microgrid topology;

[0033] A virtual synchronous machine construction module, used to construct a virtual synchronous machine in a simulation result corresponding to the target new energy storage microgrid topology according to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation;

[0034] A supercapacitor configuration module is used to design a corresponding inertia-damping-reactance control loop according to the virtual synchronous machine, and configure the supercapacitor in a simulation result corresponding to the target new energy energy storage microgrid topology based on the simulated inertia parameters, frequency variation range and voltage variation range determined from the inertia-damping-reactance control loop under preset conditions to obtain a new energy energy storage microgrid simulated topology structure;

[0035] A synchronous machine characteristic simulation module, used to simulate the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine according to the inertia-damping-reactance control loop when running the new energy storage microgrid simulation topology structure, using the configured supercapacitor as the energy storage support;

[0036] a response module, configured to obtain a target power reference value of the supercapacitor in response to the inertia characteristic, the damping characteristic and the reactance characteristic;

[0037] The analog control module is used to perform analog control on the output power of the supercapacitor according to the target power reference value.

[0038] Furthermore, the virtual synchronization mechanism building module is specifically used for:

[0039] The synchronous machine rotor motion equation is expressed by the following formula:

[0040]

[0041] Where H is the inertia time constant of the synchronous machine, in S; D is the damping coefficient of the synchronous machine; f0, f and f g They are the synchronous machine rotor rated frequency, rotor instantaneous frequency and main grid frequency, in Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the synchronous machine when the rotor speed changes, respectively, in pu;

[0042] The supercapacitor power dynamic equation is expressed by the following formula:

[0043]

[0044] Among them, C sc is the capacitance value of the supercapacitor, in F; u sc is the overcapacity voltage, in V; S0 is the rated power of the inverter of the new energy power generation system, in VA; ΔP2 is the overcapacity exchange power, in pu;

[0045] The synchronous machine rotor motion equation and the supercapacitor power dynamic equation are combined to construct the virtual synchronous machine:

[0046] ΔP1=ΔP2.

[0047] Furthermore, the supercapacitor configuration module is also used for:

[0048] Constructing a small signal model of the photovoltaic power generation system in the inertia-damping-reactance control loop;

[0049] Analyzing the photovoltaic grid-connected system of the new energy storage microgrid simulated topology structure in a first operating state according to the root locus method, wherein the first operating state is determined by the simulation parameters of the inertia-damping-reactance control loop;

[0050] The simulation parameters are optimized according to the analysis results to obtain the optimized inertia characteristics, the damping characteristics and the reactance characteristics.

[0051] Furthermore, the target new energy storage microgrid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacitance control interface that match the supercapacitor.

[0052] Furthermore, the simulation control module is specifically used for:

[0053] coupling the operating voltage of the supercapacitor with the main grid frequency;

[0054] In response to the coupling characteristic, the real-time output power of the super capacitor is dynamically adjusted based on the target power reference value.

[0055] Compared with the prior art, the embodiments of the present invention have the following advantages:

[0056] The embodiment of the present invention constructs a microgrid in simulation, constructs a virtual synchronous machine by combining the synchronous machine rotor motion equation, the power transmission equation and the supercapacitor power dynamic equation, and designs a controller for comprehensive simulation of the inertia, damping and reactance response characteristics of the synchronous machine by new energy. While flexibly simulating the inertia of the synchronous machine, the supercapacitor can be reasonably configured to simulate damping and simulate reactance, thereby comprehensively improving the stability of the operation of the new energy storage microgrid. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a schematic flow chart of a simulation control method based on supercapacitor energy storage inertia support in one embodiment of the present invention;

[0058] Figure 2 It is a schematic diagram of the topological structure of a new energy storage microgrid in one embodiment of the present invention;

[0059] Figure 3 It is a schematic diagram of the structure of an inertia-damping-reactance control circuit in one embodiment of the present invention;

[0060] Figure 4 It is a schematic diagram of the influence of the change of the simulation parameters of the control loop on the supercapacitor characteristics in one embodiment of the present invention;

[0061] Figure 5 is a small signal model diagram of a photovoltaic power generation system in one embodiment of the present invention;

[0062] Figure 6 It is a schematic diagram of the structure of an analog control system based on supercapacitor energy storage inertia support in one embodiment of the present invention. DETAILED DESCRIPTION

[0063] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] In the description of this application, the terms "first", "second", "third", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", "third", etc. may explicitly or implicitly include one or more of the feature. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0065] In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. The terms "vertical", "horizontal", "left", "right", "upper", "lower" and similar expressions used herein are only for illustrative purposes, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0066] In the description of this application, it should be noted that, unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those commonly understood by those skilled in the art. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0067] Compared with batteries, supercapacitors have significant advantages in terms of charging and discharging speed, power density, etc., and are more suitable for inertia simulation technology with fast response speed and high peak power. Therefore, this application uses supercapacitors as the energy source for inertia simulation technology. Therefore, an embodiment of the present invention provides a simulation control method based on supercapacitor energy storage inertia support. For details, please refer to Figure 1 , Figure 1 The figure shows a flow chart of a simulation control method based on supercapacitor energy storage inertia support in one embodiment of the present invention, which includes the following steps:

[0068] S1-S2, simulating the selected target new energy storage microgrid topology; constructing a virtual synchronous machine in the simulation result corresponding to the target new energy storage microgrid topology according to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation.

[0069] In the simulation environment, the selected new energy storage microgrid topology is constructed. In some embodiments of the present invention, this topology may include energy storage equipment, photovoltaic power generation system, grid-connected system, AC / DC system and load. Please refer to Figure 2 As shown, Figure 2 The topological structure diagram of a new energy storage microgrid in one embodiment of the present invention is shown. The front-end part of the topology is represented by a photovoltaic power source, and the grid-connected inverter adopts a constant DC voltage control to maintain the DC bus voltage stability and the balance of AC and DC power.

[0070] It can be understood that the rotor motion equation of the synchronous generator describes the dynamic behavior of the rotor under the action of mechanical and electromagnetic torques; the power dynamic equation of the supercapacitor describes the power change of the supercapacitor during the charging and discharging process.

[0071] The synchronous machine rotor motion equation is expressed by the following formula:

[0072]

[0073] Where H is the inertia time constant of the synchronous machine, in S; D is the damping coefficient of the synchronous machine; f0, f and f g They are the synchronous machine rotor rated frequency, rotor instantaneous frequency and main grid frequency, in Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the synchronous machine when the rotor speed changes, respectively, in pu;

[0074] The supercapacitor power dynamic equation is expressed by the following formula:

[0075]

[0076] Among them, C sc is the capacitance value of the supercapacitor, in F; u sc is the overcapacity voltage, in V; S0 is the rated power of the inverter of the new energy power generation system, in VA; ΔP2 is the overcapacity exchange power, in pu;

[0077] Based on this, the new energy storage microgrid topology constructed based on simulation first combines the rotor motion equation of the synchronous machine with the power dynamic equation of the supercapacitor. That is, ΔP1=ΔP2, then:

[0078]

[0079] In the formula, H v is the simulated inertia time constant; D v is the simulated damping coefficient; f v is the virtual rotor frequency.

[0080] Integrate both sides of the above simultaneous equations:

[0081]

[0082] Among them, u sc0 is the voltage operating neutral point of the overcapacity; 1 / s is the integral operator; K is the constant coefficient, K = 2S0 / (C sc ×f0).

[0083] For the virtual rotor frequency f v and the main network frequency f g By subtracting and integrating, we can obtain the virtual power angle δ of the supercapacitor relative to the main grid. v , expressed by the following formula:

[0084]

[0085] In the power system, the main grid frequency is an important parameter that reflects the operating status of the power grid system. When the main grid frequency changes, the rotor motion state of the synchronous machine will also change accordingly. The virtual power angle is one of the important parameters for simulating the rotor motion state of the synchronous machine. It reflects the relative position relationship between the virtual synchronous machine and the main grid. The change of the virtual power angle will affect the power output and frequency response characteristics of the virtual synchronous machine, and then reflect the influence of the synchronous machine inertia on the system frequency stability.

[0086] This step links the dynamic response of the supercapacitor with the physical characteristics of the synchronous machine through a mathematical model. Through reasonable mathematical transformation, the supercapacitor is constructed as a synchronous machine with a virtual rotor frequency. The virtual synchronous machine can simulate the inertia, damping and reactance characteristics of the synchronous machine.

[0087] S3. Design a corresponding inertia-damping-reactance control loop according to the virtual synchronous machine, and under preset conditions, based on the simulated inertia parameters, frequency variation range and voltage variation range determined from the inertia-damping-reactance control loop, configure supercapacitors in the simulation results corresponding to the target new energy energy storage microgrid topology to obtain a new energy energy storage microgrid simulation topology structure.

[0088] According to the virtual synchronous machine, an inertia-damping-reactance control loop (IDIE loop) is designed. The control loop structure is as follows: Figure 3 As shown, it can be seen that it is configured to contain supercapacitors, power controllers, DC bus, and control loops for reactance simulation, inertia, and damping simulation.

[0089] In order to reliably and effectively implement the energy storage configuration of IDIE, the embodiment of the present invention designs the overcapacitance configuration and neutral point voltage setting principle based on the IDIE scheme. In practical applications, if the overcapacitance value configured is too small, it will lead to excessive overcapacitance voltage deviation, which exceeds the adjustment range of the DC / DC converter; and if the overcapacitance value configured is too large, it will lead to unnecessary investment cost and increase of floor space.

[0090] Based on this, in order to obtain the optimal supercapacitor configuration, under the conditions of clarifying the maximum simulated inertia time constant of the IDIE scheme, the covered frequency variation range and the allowable variation range of the supercapacitor voltage, the supercapacitor is configured according to "when the main grid frequency reaches the maximum or minimum value of the covered frequency range, the supercapacitor voltage also reaches the maximum or minimum value". The configuration process is expressed by the following formula:

[0091]

[0092] Eliminate u sc0 The optimal excess capacity is:

[0093]

[0094] According to the above formula, the allowable variation range of different overcapacitance voltages [u scmin ,u scmax ], exceeding the capacity value C sc , Maximum simulated inertia time constant H max and the maximum coverage frequency offset Δf max =f max -f min The relationship between the three. Specifically, Figure 4 As shown, Figure 4 A schematic diagram showing the effect of changes in simulated parameters of a control loop on supercapacitor characteristics according to one embodiment of the present invention is shown.

[0095] It can be seen that the larger the values ​​of the maximum simulated inertia time constant and the maximum coverage frequency deviation are, the larger the required supercapacitor value is, so that more energy requirements can be met.

[0096] According to the above formula, the voltage operating neutral point u of the over-capacity voltage is obtained. sc0 :

[0097]

[0098] It can be seen from the above formula that when setting the overcapacity voltage operating neutral point, the influence of the coverage frequency variation range and the allowable variation range of the overcapacity voltage is comprehensively considered, and flexible adjustments are made according to demand to meet the overcapacity energy margin during up and down adjustments.

[0099] It is worth noting that the bidirectional DC / DC converter used in the IDIE control loop of the embodiment of the present invention includes a voltage control interface and a capacitance control interface matched with the supercapacitor, and the supercapacitor is connected to the new energy DC bus through the bidirectional DC / DC converter to realize bidirectional power exchange. The bidirectional DC / DC converter can widen the variable range of the system voltage, make more full use of the supercapacitor energy, and effectively reduce the capacitance value.

[0100] S4. When running the new energy energy storage microgrid simulation topology structure, the configured supercapacitor is used as the energy storage support, and the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine are simulated according to the inertia-damping-reactance control loop.

[0101] With the configured supercapacitor as energy storage support, the comprehensive simulation of the virtual synchronous machine begins, such as Figure 3 As shown, it can be seen that the inertia and damping characteristics of the synchronous machine are simulated in the control loop, and on this basis, the simulation of the reactance characteristics of the synchronous machine winding is further introduced, and the inertia, damping and reactance characteristics of the synchronous machine are comprehensively simulated during the whole process of frequency disturbance. The duty cycle can be adjusted by the power controller to generate the corresponding pulse width modulation signal to drive the switching device of the bidirectional DC / DC converter, and the control noise that may be caused by the frequency change rate link of the inertia simulation processing is avoided by introducing the instant main grid frequency drive control loop.

[0102] It can be understood that this step aims to comprehensively simulate the inertia, damping and reactance characteristics of the synchronous machine by controlling the active power of the supercapacitor.

[0103] In order to optimize the key simulation parameters of the control loop, in some embodiments of the present application, taking the photovoltaic power generation system as an example, a Figure 5 The small signal model of the photovoltaic power generation system in the application IDIE loop is shown.

[0104] According to the constructed photovoltaic power generation system small signal model, the root locus method is used to analyze the photovoltaic grid-connected system of the new energy storage microgrid simulation topology structure in the first operating state. The first operating state is determined by the simulation parameters of the inertia-damping-reactance control loop.

[0105] This embodiment analyzes the influence of the simulated damping coefficient, reactance coefficient and inertia time constant on the system stability during the simulation process, and optimizes the simulation parameters according to the analysis results to obtain the optimized inertia characteristics, damping characteristics and reactance characteristics. The above operation of this step can improve the performance of the virtual synchronous machine, thereby improving the stability of the power grid system.

[0106] S5. In response to the inertia characteristic, the damping characteristic, and the reactance characteristic, obtain a target power reference value of the supercapacitor.

[0107] In the process of characteristic simulation through virtual synchronous machine, in response to the inertia characteristics, damping characteristics and reactance characteristics of the synchronous machine, the virtual synchronous machine can adjust the corresponding power output according to the needs of the new energy microgrid system to maintain the supply and demand balance of the power grid system.

[0108] Specifically, in some embodiments of the present invention, the power demand of the new energy microgrid system can be calculated according to the change of the main grid frequency, and the target power reference value of the supercapacitor can be determined by combining this demand with the energy storage capacity and charging and discharging status of the supercapacitor.

[0109] S6. Perform analog control on the output power of the supercapacitor according to the target power reference value.

[0110] In the new energy storage microgrid of this embodiment, the voltage of the supercapacitor as an energy storage device and the frequency of the main grid are interrelated. When the frequency of the main grid changes, it may affect the charging and discharging state of the energy storage device, thereby changing its voltage. Conversely, the change in the voltage of the energy storage device may also affect the frequency of the main grid through power flow.

[0111] Therefore, during the simulation process, the embodiment of the present invention couples the operating voltage of the supercapacitor with the main grid frequency; in response to the coupling characteristics, the real-time output power of the supercapacitor is dynamically adjusted based on the target power reference value, so that the power output of the supercapacitor quickly tracks its power reference value.

[0112] In summary, the embodiment of the present invention constructs a virtual synchronous machine and designs a corresponding inertia-damping-reactance control loop, and reasonably configures the supercapacitor in the constructed control loop, so that the stability of the system under various operating conditions can be ensured during the simulation process; based on the energy storage support of the supercapacitor, the inertia, damping and reactance characteristics are simulated by the virtual synchronous machine to analyze the influence of these parameters on the power grid system, so as to make effective adjustments.

[0113] An embodiment of the present invention provides an analog control system based on supercapacitor energy storage inertia support. For details, see Figure 6 , Figure 6The structure diagram of the analog control system based on supercapacitor energy storage inertia support in one embodiment of the present invention is shown, including:

[0114] The grid simulation module M1 is used to simulate the selected target new energy storage microgrid topology;

[0115] A virtual synchronous machine construction module M2 is used to construct a virtual synchronous machine in the simulation result corresponding to the target new energy storage microgrid topology according to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation;

[0116] The supercapacitor configuration module M3 is used to design a corresponding inertia-damping-reactance control loop according to the virtual synchronous machine, and configure the supercapacitor in the simulation result corresponding to the target new energy energy storage microgrid topology based on the simulated inertia parameters, frequency variation range and voltage variation range determined from the inertia-damping-reactance control loop under preset conditions to obtain a new energy energy storage microgrid simulation topology structure;

[0117] The synchronous machine characteristic simulation module M4 is used to simulate the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine according to the inertia-damping-reactance control loop when running the new energy storage microgrid simulation topology structure, using the configured supercapacitor as the energy storage support;

[0118] A response module M5, configured to obtain a target power reference value of the supercapacitor in response to the inertia characteristic, the damping characteristic and the reactance characteristic;

[0119] The analog control module M6 is used to perform analog control on the output power of the supercapacitor according to the target power reference value.

[0120] In this embodiment, the virtual synchronization machine construction module M2 is specifically used for:

[0121] The synchronous machine rotor motion equation is expressed by the following formula:

[0122]

[0123] Where H is the inertia time constant of the synchronous machine, in S; D is the damping coefficient of the synchronous machine; f0, f and f g They are the synchronous machine rotor rated frequency, rotor instantaneous frequency and main grid frequency, in Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the synchronous machine when the rotor speed changes, respectively, in pu;

[0124] The supercapacitor power dynamic equation is expressed by the following formula:

[0125]

[0126] Among them, C sc is the capacitance value of the supercapacitor, in F; u sc is the overcapacity voltage, in V; S0 is the rated power of the inverter of the new energy power generation system, in VA; ΔP2 is the overcapacity exchange power, in pu;

[0127] The synchronous machine rotor motion equation and the supercapacitor power dynamic equation are combined to construct the virtual synchronous machine:

[0128] ΔP1=ΔP2.

[0129] In this embodiment, the supercapacitor configuration module M3 is further used for:

[0130] Constructing a small signal model of the photovoltaic power generation system in the inertia-damping-reactance control loop;

[0131] Analyzing the photovoltaic grid-connected system of the new energy storage microgrid simulated topology structure in a first operating state according to the root locus method, wherein the first operating state is determined by the simulation parameters of the inertia-damping-reactance control loop;

[0132] The simulation parameters are optimized according to the analysis results to obtain the optimized inertia characteristics, the damping characteristics and the reactance characteristics.

[0133] In this embodiment, the target new energy storage microgrid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacitance control interface that match the supercapacitor.

[0134] In this embodiment, the simulation control module M6 is specifically used for:

[0135] coupling the operating voltage of the supercapacitor with the main grid frequency;

[0136] In response to the coupling characteristic, the real-time output power of the super capacitor is dynamically adjusted based on the target power reference value.

[0137] The technical features and technical effects of the analog control system based on supercapacitor energy storage inertia support proposed in the embodiment of the present invention are the same as the technical features and technical effects of the analog control method based on supercapacitor energy storage inertia support proposed in the embodiment of the present invention, and will not be repeated here.

[0138] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A simulation control method based on supercapacitor energy storage inertia support, characterized in that: include: Simulate the selected target new energy storage microgrid topology; According to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation, a virtual synchronous machine in the simulation result corresponding to the target new energy storage microgrid topology is constructed; According to the virtual synchronous machine, a corresponding inertia-damping-reactance control loop is designed, and under preset conditions, based on simulated inertia parameters, frequency variation range, and voltage variation range determined from the inertia-damping-reactance control loop, a supercapacitor is configured in a simulation result corresponding to the target new energy storage microgrid topology to obtain a new energy storage microgrid simulated topology structure; When running the simulated topology structure of the new energy storage microgrid, the configured supercapacitor is used as the energy storage support, and the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine are simulated according to the inertia-damping-reactance control loop; acquiring a target power reference value of the supercapacitor in response to the inertia characteristic, the damping characteristic, and the reactance characteristic; The output power of the supercapacitor is analog-controlled according to the target power reference value.

2. The analog control method based on supercapacitor energy storage inertia support according to claim 1, characterized in that: The method of constructing a virtual synchronous machine in a simulation result corresponding to the target new energy storage microgrid topology according to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation includes: The synchronous machine rotor motion equation is expressed by the following formula: Where H is the inertia time constant of the synchronous machine, in S; D is the damping coefficient of the synchronous machine; f0, f and f g They are the synchronous machine rotor rated frequency, rotor instantaneous frequency and main grid frequency, in Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the synchronous machine when the rotor speed changes, respectively, in pu; The supercapacitor power dynamic equation is expressed by the following formula: Among them, C sc is the capacitance value of the supercapacitor, in F; u sc is the overcapacity voltage, in V; S0 is the rated power of the inverter of the new energy power generation system, in VA; ΔP2 is the overcapacity exchange power, in pu; The synchronous machine rotor motion equation and the supercapacitor power dynamic equation are combined to construct the virtual synchronous machine: ΔP1=ΔP2.

3. The analog control method based on supercapacitor energy storage inertia support according to claim 1, characterized in that: When running the new energy storage microgrid simulation topology structure, the method further includes: Constructing a small signal model of the photovoltaic power generation system in the inertia-damping-reactance control loop; Analyzing the photovoltaic grid-connected system of the new energy storage microgrid simulated topology structure in a first operating state according to the root locus method, wherein the first operating state is determined by the simulation parameters of the inertia-damping-reactance control loop; The simulation parameters are optimized according to the analysis results to obtain the optimized inertia characteristics, the damping characteristics and the reactance characteristics.

4. The analog control method based on supercapacitor energy storage inertia support according to claim 1, characterized in that: The target new energy storage microgrid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacitance control interface matched with the supercapacitor.

5. The analog control method based on supercapacitor energy storage inertia support according to claim 2, characterized in that: The analog control of the output power of the supercapacitor according to the target power reference value includes: coupling the operating voltage of the supercapacitor with the main grid frequency; In response to the coupling characteristic, the real-time output power of the super capacitor is dynamically adjusted based on the target power reference value.

6. An analog control system based on supercapacitor energy storage inertia support, characterized in that: include: The grid simulation module is used to simulate the selected target new energy storage microgrid topology; A virtual synchronous machine construction module, used to construct a virtual synchronous machine in a simulation result corresponding to the target new energy storage microgrid topology according to the synchronous machine rotor motion equation and the supercapacitor power dynamic equation; A supercapacitor configuration module is used to design a corresponding inertia-damping-reactance control loop according to the virtual synchronous machine, and configure the supercapacitor in a simulation result corresponding to the target new energy energy storage microgrid topology based on the simulated inertia parameters, frequency variation range and voltage variation range determined from the inertia-damping-reactance control loop under preset conditions to obtain a new energy energy storage microgrid simulated topology structure; A synchronous machine characteristic simulation module, used to simulate the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine according to the inertia-damping-reactance control loop when running the new energy storage microgrid simulation topology structure, using the configured supercapacitor as the energy storage support; a response module, configured to obtain a target power reference value of the supercapacitor in response to the inertia characteristic, the damping characteristic and the reactance characteristic; The analog control module is used to perform analog control on the output power of the supercapacitor according to the target power reference value.

7. The analog control system based on supercapacitor energy storage inertia support according to claim 6, characterized in that: The virtual synchronization mechanism building module is specifically used for: The synchronous machine rotor motion equation is expressed by the following formula: Where H is the inertia time constant of the synchronous machine, in S; D is the damping coefficient of the synchronous machine; f0, f and f g They are the synchronous machine rotor rated frequency, rotor instantaneous frequency and main grid frequency, in Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the synchronous machine when the rotor speed changes, respectively, in pu; The supercapacitor power dynamic equation is expressed by the following formula: Among them, C sc is the capacitance value of the supercapacitor, in F; u sc is the overcapacity voltage, in V; S0 is the rated power of the inverter of the new energy power generation system, in VA; ΔP2 is the overcapacity exchange power, in pu; The synchronous machine rotor motion equation and the supercapacitor power dynamic equation are combined to construct the virtual synchronous machine: ΔP1=ΔP2.

8. The analog control system based on supercapacitor energy storage inertia support according to claim 6, characterized in that: The supercapacitor configuration module is also used for: Constructing a small signal model of the photovoltaic power generation system in the inertia-damping-reactance control loop; Analyzing the photovoltaic grid-connected system of the new energy storage microgrid simulated topology structure in a first operating state according to the root locus method, wherein the first operating state is determined by the simulation parameters of the inertia-damping-reactance control loop; The simulation parameters are optimized according to the analysis results to obtain the optimized inertia characteristics, the damping characteristics and the reactance characteristics.

9. The analog control system based on supercapacitor energy storage inertia support according to claim 6, characterized in that: The target new energy storage microgrid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacitance control interface matched with the supercapacitor.

10. The analog control system based on supercapacitor energy storage inertia support according to claim 7, characterized in that: The analog control module is specifically used for: coupling the operating voltage of the supercapacitor with the main grid frequency; In response to the coupling characteristic, the real-time output power of the super capacitor is dynamically adjusted based on the target power reference value.

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