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

Abstract

The application discloses a kind of based on supercapacitor energy storage inertia support analog control method and system, the method includes the simulation of selected new energy energy storage microgrid topology;According to the rotor motion equation of synchronous machine and the power dynamic equation of supercapacitor, construct virtual synchronous machine;According to the corresponding inertia-damping-reactance control loop of virtual synchronous machine design, and based on the simulation inertia parameter determined from control loop, frequency variation range and voltage variation range under preset condition, supercapacitor is configured;With the supercapacitor of configuration as energy storage support, according to inertia-damping-reactance control loop simulates the inertia characteristic, damping characteristic and reactance characteristic of virtual synchronous machine;In response to inertia characteristic, damping characteristic and reactance characteristic, obtain the target power reference value of supercapacitor;According to target power reference value, the output power of supercapacitor is analog controlled;It can be simulated by reasonable configuration to synchronous machine characteristic, and the stability of power grid is comprehensively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power grid control, in particular to a simulation control method and system based on super capacitor energy storage inertia support. BACKGROUND

[0002] In a new energy storage micro-grid, due to the intermittency and uncertainty of renewable energy such as solar and wind energy, the stability and response speed of the system become key problems.

[0003] As a high-performance energy storage element, super capacitor has the characteristics of fast charging and discharging and high power density. However, how to effectively configure and use super capacitor to maximize its role in new energy storage micro-grid is a technical problem.

[0004] In practical applications, new energy storage micro-grid with super capacitor introduced needs to be simulated and controlled, but the existing simulation control method is subject to the configuration defects of super capacitor, resulting in poor inertia simulation effect, and the final simulation control result cannot effectively play the energy storage advantage of super capacitor, and thus cannot effectively control the characteristics of new energy grid units in the actual control process.

[0005] Therefore, how to reasonably configure the super capacitor to improve the simulation control effect has become a technical problem to be solved by those skilled in the art. SUMMARY

[0006] The present application provides a simulation control method based on super capacitor energy storage inertia support to solve the problem of how to reasonably configure the super capacitor and effectively simulate the characteristics of synchronous machines to optimize the control strategy of virtual synchronous machines and improve the accuracy of the analysis of the characteristics of the power grid system.

[0007] To solve the above technical problems, the present application provides a simulation control method based on super capacitor energy storage inertia support, comprising:

[0008] simulate the selected target new energy storage micro-grid topology;

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

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

[0011] In running the new energy storage micro-grid simulation topology, the super capacitor is configured as a storage support, and the inertia-damping-reactance control loop is used to simulate the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine;

[0012] In response to the inertia characteristics, the damping characteristics and the reactance characteristics, the target power reference value of the super capacitor is obtained;

[0013] According to the target power reference value, the output power of the super capacitor is simulated and controlled.

[0014] Further, the virtual synchronous machine in the simulation result corresponding to the target new energy storage micro-grid topology is constructed, including:

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

[0016]

[0017] Wherein, H is the inertia time constant of the synchronous machine, and the unit is S; D is the damping coefficient of the synchronous machine; f0, f and f g are the rated frequency of the synchronous machine rotor, the instantaneous frequency of the rotor and the main grid frequency, respectively, and the unit is Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the rotor speed change of the synchronous machine, respectively, and the unit is p.u.;

[0018] The super capacitor power dynamic equation is represented by the following formula:

[0019]

[0020] Wherein, C sc is the capacitance value of the super capacitor, and the unit is F; u sc is the super capacitor voltage, and the unit is V; S0 is the rated power of the new energy generation system inverter, and the unit is VA; ΔP2 is the exchange power of the super capacitor, and the unit is p.u.;

[0021] The synchronous machine rotor motion equation and the super capacitor power dynamic equation are solved to construct the virtual synchronous machine:

[0022] ΔP1=ΔP2。

[0023] Further, in running the new energy storage micro-grid simulation topology, the method further comprises:

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

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

[0026] And according to the analysis result, the simulation parameters are optimized, and the optimized inertia characteristic, damping characteristic and reactance characteristic are obtained.

[0027] Further, the target new energy storage micro-grid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacitance value control interface matched with the super capacitor.

[0028] Further, the simulation control of the output power of the super capacitor according to the target power reference value comprises:

[0029] The operating voltage of the super capacitor is coupled 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 application provides a simulation control system based on super capacitor energy storage inertia support, comprising:

[0032] A power grid simulation module is used to simulate a selected target new energy storage micro-grid topology;

[0033] A virtual synchronous machine modeling module is used to construct a virtual synchronous machine in the simulation result corresponding to the target new energy storage micro-grid topology according to the synchronous machine rotor motion equation and the super capacitor power dynamic equation;

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

[0035] A synchronous machine characteristic simulation module is used to simulate the inertia characteristic, damping characteristic and reactance characteristic of the virtual synchronous machine according to the inertia-damping-reactance control loop when the new energy storage micro-grid simulation topology structure is running, with the configured super capacitor as the energy storage support;

[0036] A response module is used to obtain a target power reference value of the super capacitor in response to the inertia characteristic, the damping characteristic and the reactance characteristic.

[0037] analog control module, configured to analogically control output power of the super capacitor according to the target power reference value.

[0038] Further, the virtual synchronous mechanism modeling module is specifically configured to:

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

[0040]

[0041] wherein H is a synchronous machine inertia time constant, with a unit of S; D is a synchronous machine damping coefficient; f0, f and f g are a synchronous machine rotor rated frequency, a rotor real-time frequency and a main grid frequency, respectively, with a unit of Hz; P m , P e and ΔP1 are a mechanical power of the synchronous machine, an electromagnetic power of the synchronous machine and an exchange power when a rotor speed changes, respectively, with a unit of p.u.;

[0042] The super capacitor power dynamic equation is represented by the following formula:

[0043]

[0044] wherein C sc is a capacitance value of the super capacitor, with a unit of F; u sc is a super capacitor voltage, with a unit of V; S0 is a rated power of an inverter of a new energy power generation system, with a unit of VA; ΔP2 is a super capacitor exchange power, with a unit of p.u.;

[0045] The synchronous machine rotor motion equation and the super capacitor power dynamic equation are solved to construct the virtual synchronous machine:

[0046] ΔP1=ΔP2.

[0047] Further, the super capacitor configuration module is further configured to:

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

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

[0050] and optimize the analog parameters according to an analysis result to obtain optimized inertia characteristics, damping characteristics and reactance characteristics.

[0051] Further, the target new energy storage micro-grid topology comprises a bidirectional DC / DC converter, and the bidirectional DC / DC converter comprises a voltage control interface and a capacitance value control interface matched with the super capacitor.

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

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

[0054] in response to the coupling characteristics, dynamically adjusting the real-time output power of the super capacitor based on the target power reference value.

[0055] Compared with the prior art, the beneficial effects of the embodiment of the present application are at least one of the following:

[0056] The embodiment of the present application can construct a micro-grid in simulation, and can construct a virtual synchronous machine by simultaneously constructing a synchronous machine rotor motion equation, a power transmission equation and a super capacitor power dynamic equation, and can design a controller for comprehensively simulating the inertia, damping and reactance response characteristics of the synchronous machine, so as to flexibly simulate the inertia of the synchronous machine, and to simulate the damping and the reactance by reasonably configuring the super capacitor, thereby comprehensively improving the stability of the new energy storage micro-grid operation. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 is a simulation control method flow diagram based on super capacitor energy storage inertia support in one of the embodiments of the present application;

[0058] Figure 2 is a new energy storage micro-grid topology structure diagram in one of the embodiments of the present application;

[0059] Figure 3 is an inertia-damping-reactance control loop structure diagram in one of the embodiments of the present application;

[0060] Figure 4 is a diagram showing the influence of the simulation parameter changes of the control loop on the characteristics of the super capacitor in one of the embodiments of the present application;

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

[0062] Figure 6 is a simulation control system structure diagram based on super capacitor energy storage inertia support in one of the embodiments of the present application. DETAILED DESCRIPTION

[0063] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described, obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments, and the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0064] In the description of the present application, the terms "first", "second", "third" and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second", "third" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0065] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or it can be the communication inside two elements. The terms "vertical", "horizontal", "left", "right", "up", "down" and similar expressions used herein are only for the purpose of description, and cannot be understood as indicating or implying 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 limiting the present application. 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 meaning of the above terms in the present application can be understood in specific cases.

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

[0067] Compared with the battery, the super capacitor has significant advantages in charging and discharging speed, power density and the like, and is more suitable for inertia simulation technology with fast response speed and high peak power, so the present application uses the super capacitor as the energy source of the inertia simulation technology. Therefore, an embodiment of the present application provides a simulation control method based on super capacitor energy storage inertia support, and for details, please refer to Figure 1 ,Figure 1 The flow chart of the simulation control method based on super capacitor energy storage inertia support in one embodiment of the application is shown, which includes the following steps:

[0068] S1-S2, simulate the selected target new energy storage micro-grid topology; according to the synchronous machine rotor motion equation and the super capacitor power dynamic equation, construct the virtual synchronous machine in the simulation results corresponding to the target new energy storage micro-grid topology.

[0069] In the simulation environment, the selected new energy storage micro-grid topology is constructed, which in some embodiments of the application can include energy storage devices, photovoltaic power generation systems, grid-connected systems, AC / DC systems and loads. Please refer to Figure 2 shown, Figure 2 The new energy storage micro-grid topology structure diagram in one embodiment of the application is shown. The front part of the topology is represented as a photovoltaic power supply, and the grid-connected inverter adopts constant DC voltage control to maintain the stability of the DC bus voltage and the balance of AC / 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 torque; the power dynamic equation of the super capacitor describes the power change of the super capacitor in the charging and discharging process.

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

[0072]

[0073] Wherein, H is the inertia time constant of the synchronous machine, with the unit of S; D is the damping coefficient of the synchronous machine; f0, f and f g are the rated frequency of the synchronous machine rotor, the instantaneous frequency of the rotor and the main grid frequency, respectively, with the unit of Hz; P m , P e and ΔP1 are the mechanical power, electromagnetic power and exchange power of the rotor speed change of the synchronous machine, respectively, with the unit of p.u.;

[0074] The super capacitor power dynamic equation is represented by the following formula:

[0075]

[0076] Wherein, C sc is the capacitance value of the super capacitor, with the unit of F; u sc is the super capacitor voltage, with the unit of V; S0 is the rated power of the new energy power generation system inverter, with the unit of VA; ΔP2 is the exchange power of the super capacitor, with the unit of p.u.;

[0077] Based on this, based on the simulation of the new energy storage micro-grid topology, first, the rotor motion equation of the synchronous machine and the power dynamic equation of the super capacitor are solved. That is, make ΔP1=ΔP2, then:

[0078]

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

[0080] Integrate both sides of the above formula:

[0081]

[0082] Where, u sc0 is the voltage operating neutral point of the super capacitor; 1 / s is the integral operator; K is a constant, K=2S0 / (C sc ×f0).

[0083] The virtual rotor frequency f v and the main grid frequency f g are subtracted and integrated to obtain the virtual power angle δ v of the super capacitor relative to the main grid, which is represented by the following formula:

[0084]

[0085] In the power system, the main grid frequency is an important parameter reflecting the operation state 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 inertia of the synchronous machine on the frequency stability of the system.

[0086] This step links the dynamic response of the super capacitor to the physical characteristics of the synchronous machine through a mathematical model. Through reasonable mathematical transformation, the super capacitor 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, according to the virtual synchronous machine, design a corresponding inertia-damping-reactance control loop, and based on the simulation inertia parameters, frequency variation range and voltage variation range determined from the inertia-damping-reactance control loop under the preset conditions, configure the super capacitor in the simulation results corresponding to the target new energy storage micro-grid topology, to obtain the new energy storage micro-grid simulation topology structure.

[0088] According to the virtual synchronous machine, an inertia-damping-reactance control loop (IDIE loop) is designed, and the control loop structure is as shown in Figure 3 It can be seen that it is configured to contain a super capacitor, a power controller, a DC bus, and a control loop for reactance simulation, inertia simulation, and damping simulation.

[0089] In order to reliably and effectively realize the energy storage configuration of IDIE, the embodiment of the application designs a super capacitor configuration and neutral point voltage setting principle based on the IDIE scheme. In actual application, if the configured super capacitor value is too small, it will cause a too large super capacitor voltage deviation, which exceeds the adjustment range of the DC / DC converter; and if the configured super capacitor value is too large, it will cause unnecessary investment cost and increase of land area.

[0090] Based on this, in order to obtain the optimal super capacitor configuration, under the condition of clearly defining the maximum simulated inertia time constant of the IDIE scheme, the frequency variation range covered, and the allowable variation range of the super capacitor voltage, the super capacitor is configured according to "when the main grid frequency reaches the maximum or minimum value of the covered frequency range, the super capacitor voltage also reaches the maximum or minimum value", and the configuration process is represented by the following formula:

[0091]

[0092] Eliminate u sc0 , the optimal super capacitor value is:

[0093]

[0094] According to the above formula, the relationship among the super capacitor value C sc , the maximum simulated inertia time constant H max , and the maximum covered frequency deviation Δf max =f max -f min in the allowable variation range of the super capacitor voltage [u scmin , u scmax ] can be drawn. Specifically, as shown in Figure 4 , as shown in Figure 4 , the influence diagram of the simulation parameter change of the control loop of one embodiment of the application on the super capacitor characteristics.

[0095] It can be seen that the greater the maximum simulated inertia time constant and the maximum covered frequency deviation, the greater the required super capacitor value, so as to meet more energy demand.

[0096] According to the above formula, the voltage running neutral point u sc0 of the super capacitor voltage is obtained:

[0097]

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

[0099] It is worth noting that the bidirectional DC / DC converter used in the IDIE control loop of the embodiment of the application includes a voltage control interface and a capacitance value control interface matched with the super capacitor, and the super capacitor is connected to the new energy direct current bus through the bidirectional DC / DC converter to realize bidirectional power exchange. The variable range of the system voltage can be widened by the bidirectional DC / DC converter, and the super capacitor energy can be more fully utilized, and the capacitance value can be effectively reduced.

[0100] S4, in the process of running the new energy storage micro-grid simulation topology, the configured super capacitor is used as energy storage support, and the inertia-damping-reactance control loop is used to simulate the inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine.

[0101] The configured super capacitor is used as energy storage support to start the comprehensive simulation of the virtual synchronous machine, as shown in Figure 3 It can be seen that the inertia and damping characteristics of the synchronous machine are simulated in the control loop, and the winding reactance characteristics of the synchronous machine are further introduced for simulation, and the inertia, damping and reactance characteristics of the synchronous machine are comprehensively simulated in the whole process of frequency disturbance. The duty cycle can be adjusted by the power controller to generate a corresponding pulse width modulation signal to drive the switching devices of the bidirectional DC / DC converter, and the control noise caused by the inertia simulation processing frequency change rate link can be avoided by introducing the instantaneous main grid frequency driving 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 super capacitor.

[0103] To optimize the key simulation parameters of the control loop, in some embodiments of the application, a photovoltaic power generation system is taken as an example, and a small signal model of the photovoltaic power generation system in the IDIE loop is built as shown in Figure 5

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

[0105] ​The embodiment analyzes the influence of the simulation damping coefficient, the simulation reactance coefficient and the simulation inertia time constant on the system stability in the simulation process, and optimizes the simulation parameters according to the analysis result, so as to obtain the optimized inertia characteristic, the optimized damping characteristic and the optimized reactance characteristic. The above operation in the 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, obtaining a target power reference value of the super capacitor.

[0107] In the process of simulating the characteristics by the virtual synchronous machine, in response to the inertia characteristic, the damping characteristic and the reactance characteristic of the synchronous machine, the virtual synchronous machine can adjust the corresponding power output according to the demand of the new energy micro-grid system, so as to maintain the balance between supply and demand of the power grid system.

[0108] Specifically, in some embodiments of the present application, the power demand of the new energy micro-grid system can be calculated according to the change of the main grid frequency, and the target power reference value of the super capacitor can be determined in combination with the energy storage capacity and the charge and discharge state of the super capacitor.

[0109] S6, simulating and controlling the output power of the super capacitor according to the target power reference value.

[0110] In the new energy storage micro-grid of the embodiment, the voltage of the super capacitor as the energy storage device and the frequency of the main grid are related to each other. When the frequency of the main grid changes, it may affect the charge and discharge state of the energy storage device, thereby changing its voltage. Conversely, the change of the voltage of the energy storage device may also affect the frequency of the main grid through power flow.

[0111] Therefore, in the simulation process, the running voltage of the super capacitor is coupled with the frequency of the main grid in the embodiment of the present application; 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, that is, the power output of the super capacitor is made to quickly track the power reference value.

[0112] In summary, the embodiment of the present application constructs a virtual synchronous machine and designs a corresponding inertia-damping-reactance control loop, and in the constructed control loop, the super capacitor is reasonably configured, so that the stability of the system under various operating conditions can be ensured in the simulation process; based on the energy storage support of the super capacitor, the inertia, damping and reactance characteristics of the virtual synchronous machine are simulated to analyze the influence of these parameters on the power grid system, thereby effectively adjusting.

[0113] An embodiment of the present application provides a simulation control system based on super capacitor energy storage inertia support, specifically, please refer to Figure 6 , Figure 6A schematic diagram of a simulation control system structure based on super capacitor energy storage inertia support in one embodiment of the application is shown, comprising:

[0114] A power grid simulation module M1 is configured to simulate a selected target new energy storage micro-grid topology;

[0115] A virtual synchronous machine modeling module M2 is configured to construct a virtual synchronous machine in a simulation result corresponding to the target new energy storage micro-grid topology according to a synchronous machine rotor motion equation and a super capacitor power dynamic equation;

[0116] A super capacitor configuration module M3 is configured to design a corresponding inertia-damping-reactance control loop according to the virtual synchronous machine, and configure a super capacitor in the simulation result corresponding to the target new energy storage micro-grid topology based on analog inertia parameters, a frequency variation range and a voltage variation range determined from the inertia-damping-reactance control loop under a preset condition, to obtain a new energy storage micro-grid simulation topology structure;

[0117] A synchronous machine characteristic simulation module M4 is configured to simulate inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine according to the inertia-damping-reactance control loop when the new energy storage micro-grid simulation topology structure is running, with the configured super capacitor as energy support;

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

[0119] A simulation control module M6 is configured to simulate control output power of the super capacitor according to the target power reference value.

[0120] In this embodiment, the virtual synchronous machine modeling module M2 is specifically configured to:

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

[0122]

[0123] Wherein, H is a synchronous machine inertia time constant, with a unit of S; D is a synchronous machine damping coefficient; f0, f and f g are a synchronous machine rotor rated frequency, a rotor instantaneous frequency and a main grid frequency, respectively, with a unit of Hz; P m , P e and ΔP1 are a synchronous machine mechanical power, an electromagnetic power and an exchange power when a rotor speed changes, respectively, with a unit of p.u.;

[0124] The super capacitor power dynamic equation is represented by the following formula:

[0125]

[0126] wherein, C sc is the super-capacitor value, in F; u sc is the super-capacitor voltage, in V; S0 is the rated power of the new energy power generation system inverter, in VA; and ΔP2 is the super-capacitor exchange power, in p.u.

[0127] The synchronous machine rotor motion equation and the super-capacitor power dynamic equation are solved to construct the virtual synchronous machine:

[0128] ΔP1=ΔP2.

[0129] In the embodiment, the super-capacitor configuration module M3 is further configured to:

[0130] A small signal model of the photovoltaic power generation system in the inertia-damping-reactance control loop is constructed.

[0131] The photovoltaic grid-connected system in the simulated topology structure of the new energy storage micro-grid in a first operating state is analyzed 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 result, and the optimized inertia characteristic, damping characteristic and reactance characteristic are obtained.

[0133] In the embodiment, the target new energy storage micro-grid 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 super-capacitor.

[0134] In the embodiment, the simulation control module M6 is specifically configured to:

[0135] The operating voltage of the super-capacitor is coupled 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 simulation control system based on super-capacitor energy storage inertia support proposed in the embodiments of the present application are the same as those of the simulation control method based on super-capacitor energy storage inertia support proposed in the embodiments of the present application, and will not be repeated here.

[0138] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, several modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method of analog control based on supercapacitor energy storage inertia support, characterized in that, The method comprises: performing simulation on a selected target new energy storage micro-grid topology; constructing a virtual synchronous machine in simulation results corresponding to the target new energy storage micro-grid topology according to a synchronous machine rotor motion equation and a super capacitor power dynamic equation; configuring a super capacitor in simulation results corresponding to the target new energy storage micro-grid topology according to an inertia-damping-reactance control loop designed according to the virtual synchronous machine, and based on analog inertia parameters, a frequency variation range and a voltage variation range determined from the inertia-damping-reactance control loop under a preset condition, to obtain a new energy storage micro-grid simulation topology structure; when the new energy storage micro-grid simulation topology structure is running, taking the configured super capacitor as energy storage support, simulating inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine according to the inertia-damping-reactance control loop; in response to the inertia characteristics, the damping characteristics and the reactance characteristics, obtaining a target power reference value of the super capacitor; simulating and controlling the output power of the super capacitor according to the target power reference value.

2. The supercapacitor energy storage inertia support based analog control method of claim 1, wherein, The method of constructing a virtual synchronous machine in simulation results corresponding to the target new energy storage micro-grid topology according to a synchronous machine rotor motion equation and a super capacitor power dynamic equation comprises: The synchronous machine rotor motion equation is represented by the following formula: where H is the inertia time constant of the synchronous machine, with unit of S; D is the damping coefficient of the synchronous machine; f0, f and f g are the rated frequency of the rotor of the synchronous machine, the instantaneous frequency of the rotor and the frequency of the main grid, respectively, with unit of Hz; P m , P e and ΔP1 are the mechanical power, the electromagnetic power and the exchange power when the rotor speed changes, respectively, with unit of p.u.; The super capacitor power dynamic equation is represented by the following formula: wherein C sc is an over-rating capacitance value in F; u sc is an over-rating voltage in V; S0 is the rated power of the new energy power generation system inverter in VA; and ΔP2 is an over-rating exchange power in p.u. The virtual synchronous machine is constructed by simultaneously solving the synchronous machine rotor motion equation and the super capacitor power dynamic equation: ΔP1=ΔP2.

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

4. The method of analog control based on supercapacitive energy storage inertia support according to claim 1, characterized in that, The target new energy storage micro-grid topology comprises a bidirectional DC / DC converter, and the bidirectional DC / DC converter comprises a voltage control interface and a capacitance value control interface matched with the super capacitor.

5. The method of analog control based on supercapacitive energy storage inertia support according to claim 2, characterized in that, The method of simulating and controlling the output power of the super capacitor according to the target power reference value comprises: coupling the operating voltage of the super capacitor with the main grid frequency; in response to the coupling characteristics, dynamically adjusting the real-time output power of the super capacitor based on the target power reference value.

6. A simulation control system based on supercapacitor energy storage inertia support, characterized by, The method comprises: a power grid simulation module for simulating a selected target new energy storage micro-grid topology; a virtual synchronous machine modeling module for constructing a virtual synchronous machine in simulation results corresponding to the target new energy storage micro-grid topology according to a synchronous machine rotor motion equation and a super capacitor power dynamic equation; The super capacitor configuration module is configured to configure a super capacitor in a simulation result corresponding to the target new energy storage micro-grid topology according to an inertia-damping-reactance control loop corresponding to the virtual synchronous machine, and based on an analog inertia parameter, a frequency variation range and a voltage variation range determined from the inertia-damping-reactance control loop under a preset condition, to obtain a new energy storage micro-grid simulation topology structure. The synchronous machine characteristic simulation module is configured to simulate inertia characteristics, damping characteristics and reactance characteristics of the virtual synchronous machine according to the inertia-damping-reactance control loop while running the new energy storage micro-grid simulation topology structure with the configured super capacitor as energy storage support. The response module is configured to obtain a target power reference value of the super capacitor in response to the inertia characteristics, the damping characteristics and the reactance characteristics. The simulation control module is configured to simulate control output power of the super capacitor according to the target power reference value.

7. The supercapacitor energy storage inertia support based analog control system of claim 6, wherein, The virtual synchronous machine modeling module is specifically configured to: The synchronous machine rotor motion equation is represented by the following formula: where H is the inertia time constant of the synchronous machine, with unit of S; D is the damping coefficient of the synchronous machine; f0, f and f g are the rated frequency of the rotor of the synchronous machine, the instantaneous frequency of the rotor and the frequency of the main grid, respectively, with unit of Hz; P m , P e and ΔP1 are the mechanical power, the electromagnetic power and the exchange power when the rotor speed changes, respectively, with unit of p.u.; The super capacitor power dynamic equation is represented by the following formula: wherein C sc is an over-rating capacitance value in F; u sc is an over-rating voltage in V; S0 is the rated power of the new energy power generation system inverter in VA; and ΔP2 is an over-rating exchange power in p.u. The virtual synchronous machine is constructed by simultaneously solving the synchronous machine rotor motion equation and the super capacitor power dynamic equation: ΔP1 = ΔP2.

8. The supercapacitor energy storage inertia support based analog control system of claim 6, wherein, The super capacitor configuration module is further configured to: construct a small signal model of a photovoltaic power generation system in the inertia-damping-reactance control loop; analyze a photovoltaic grid-connected system of the new energy storage micro-grid simulation topology structure in a first operating state according to a root locus method, wherein the first operating state is determined by simulation parameters of the inertia-damping-reactance control loop; and optimize the simulation parameters according to an analysis result, to obtain optimized inertia characteristics, damping characteristics and reactance characteristics.

9. The supercapacitor energy storage inertia support based analog control system of claim 6, wherein, The target new energy storage micro-grid topology includes a bidirectional DC / DC converter, and the bidirectional DC / DC converter includes a voltage control interface and a capacity control interface matched with the super capacitor.

10. The supercapacitor energy storage inertia support based analog control system of claim 7, wherein, The simulation control module is specifically configured to: couple operating voltage of the super capacitor with a main grid frequency; and in response to the coupling characteristics, dynamically adjust real-time output power of the super capacitor based on the target power reference value.

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