Energy storage auxiliary frequency modulation and voltage regulation system

Abstract

The invention relates to the technical field of photovoltaic power generation, in particular to an energy storage auxiliary frequency modulation and voltage regulation system. Comprising a prediction unit used for establishing a plurality of adjustment periods and generating an expected power curve in each adjustment period according to a preset power prediction model; the energy storage unit comprises a plurality of primary energy storage modules and a single secondary energy storage module; the monitoring unit is used for acquiring operation parameters of the photovoltaic generator and state parameters of the energy storage unit; and the central control unit is used for sequentially generating adjustment plans in each adjustment period and setting operation parameters of the energy storage unit according to the adjustment plans. A plurality of time intervals are established in a single adjustment period through a predicted expected power curve, sub-adjustment strategies in each time interval are set according to the real-time state of a primary energy storage module, auxiliary frequency modulation and voltage regulation are performed on a photovoltaic generator in the single adjustment period, stable operation of a photovoltaic system is ensured, and the energy storage efficiency is improved. The loss of the energy storage module caused by over-charging or over-discharging is reduced, and the service life of the energy storage module is prolonged.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic power generation technology, and in particular to an energy storage-assisted frequency and voltage regulation system. Background Art

[0002] As one of the most mature and promising renewable energy sources, photovoltaic power generation has maintained a strong development momentum in recent years. Photovoltaic power generation has the following limitations: Since solar panels are affected by light and temperature, when the external environment changes rapidly, the photovoltaic power generation power will also change rapidly, and it is impossible to guarantee stable power output to the power grid. Therefore, in order to stabilize the output power of photovoltaic power generation, an energy storage system is usually added to the photovoltaic power generation system.

[0003] However, the current energy storage system has problems of overcharging and over-discharging during frequency and voltage regulation, which greatly affects the service life of the energy storage device. At the same time, the existing energy storage system often uses batteries, which have high energy density and can provide power support for a long time, but have low power density and slow reaction speed and cannot cope with sudden power changes, resulting in reduced frequency and voltage regulation efficiency. Summary of the invention

[0004] The purpose of this application is: to solve the above technical problems, this application provides an energy storage assisted frequency and voltage regulation system, which aims to improve the frequency and voltage regulation efficiency of the energy storage system, ensure the stable operation of the photovoltaic system, and increase the service life of the energy storage system.

[0005] In some embodiments of the present application, a primary energy storage module (i.e., a battery) is additionally provided, and multiple time intervals are established in a single regulation cycle through a predicted expected power curve, so that a sub-regulation strategy in each time interval is set according to the real-time state of the primary energy storage module, and auxiliary frequency and voltage regulation is performed on the photovoltaic generator in a single regulation cycle, thereby ensuring the stable operation of the photovoltaic system, reducing the loss of a single energy storage module caused by overcharging or over-discharging problems, and increasing the operating life of the energy storage module.

[0006] In some embodiments of the present application, a secondary energy storage module (i.e., a supercapacitor) is added, and multiple monitoring time nodes are set according to the fluctuation evaluation value within a single cycle, so as to monitor the real-time power of the photovoltaic generator, promptly issue an early warning for abnormal power fluctuations, and respond quickly through the secondary energy storage module to improve the efficiency of auxiliary frequency and voltage regulation.

[0007] In some embodiments of the present application, an energy storage-assisted frequency and voltage regulation system is provided, comprising:

[0008] A prediction unit, used to establish multiple regulation cycles and generate an expected power curve in each regulation cycle according to a preset power prediction model;

[0009] An energy storage unit, comprising a plurality of primary energy storage modules and a single secondary energy storage module;

[0010] A monitoring unit, used to obtain operating parameters of the photovoltaic generator and status parameters of the energy storage unit;

[0011] The central control unit is used to sequentially generate the regulation plan within each regulation cycle and set the operating parameters of the energy storage unit according to the regulation plan.

[0012] In some embodiments of the present application, the central control unit includes:

[0013] The first processing module is used to establish a primary energy storage module sequence A, A = (a1, a2 ... ai ... an), where ai is the i-th primary energy storage module and n is the number of primary energy storage modules;

[0014] A second processing module is used to set a primary regulation plan for the current cycle according to the power prediction curve of the current regulation cycle, and set operating parameters of each primary energy storage module according to the primary regulation plan;

[0015] The third processing module is used to generate a fluctuation evaluation value of the current adjustment period and set a plurality of monitoring time nodes according to the fluctuation evaluation value;

[0016] The third processing module is also used to determine whether to generate a secondary adjustment plan according to a preset monitoring time node.

[0017] In some embodiments of the present application, the second processing module is further used for:

[0018] Generate multiple time intervals according to the power prediction curve of the current regulation cycle;

[0019] Establish a time interval sequence T, T = (t1, t2...ti...tn), where ti is the i-th time interval in the current adjustment cycle; n is the number of time intervals in the current adjustment cycle;

[0020] According to the time interval sequence T, the i-th time interval is sequentially set as the target time interval;

[0021] Generate an expected remaining power sequence C within the target time interval according to the preset simulation model, C = (c1, c2...ci...cm), where ci is the expected remaining power of the i-th primary energy storage module at the start time node of the target time interval;

[0022] Obtaining the expected power sub-curve within the target time interval;

[0023] Generate a sub-regulation strategy for the target time interval according to the expected power sub-curve and the expected remaining power sequence C;

[0024] Generate sub-regulation strategies for each time interval in turn;

[0025] Generate a first-level adjustment plan for the current adjustment cycle based on all sub-adjustment strategies.

[0026] In some embodiments of the present application, the generating of the sub-adjustment strategy of the target time interval includes:

[0027] A first power threshold C1 and a second power threshold C2 are preset, and C1<C2;

[0028] generating a regulation mode for the target time interval according to the expected power sub-curve for the target time interval;

[0029] When the target time interval is in the first-level adjustment mode;

[0030] If ci<C1, the i-th primary energy storage module is eliminated in the target time interval;

[0031] Generate a sub-regulation strategy for the target time interval according to the elimination result and the expected power sub-curve of the target time interval;

[0032] When the target time interval is in the secondary adjustment mode;

[0033] If ci>C2, the i-th primary energy storage module is eliminated in the target time interval;

[0034] A sub-regulation strategy for the target time interval is generated according to the elimination result and the expected power sub-curve of the target time interval.

[0035] In some embodiments of the present application, the central control unit further includes:

[0036] A correction module, used to obtain a time interval sequence T according to the current adjustment cycle;

[0037] Set the start time node of each time interval as the feedback time node;

[0038] Obtain the state parameters of each primary energy storage module and the operating parameters of the photovoltaic generator at the current feedback time node;

[0039] Generate an operation deviation value d of the current feedback time node, and determine whether to generate a correction instruction at the current feedback time node based on the operation deviation value d.

[0040] In some embodiments of the present application, when generating the running deviation value d of the current feedback time node, it includes:

[0041]

[0042] Among them, e3 is the preset third weight coefficient; e4 is the preset fourth weight coefficient; Q3 is the preset third fixed coefficient; Q4 is the preset fourth fixed coefficient; c 1i is the real-time remaining power of the i-th primary energy storage module at the current feedback time node; c' i is the expected remaining power of the i-th primary energy storage module at the current feedback time node; P is the deviation reference value set based on the overlap between the actual power curve and the expected power sub-curve of the photovoltaic generator in a time interval before the current feedback time node.

[0043] In some embodiments of the present application, when determining whether a correction instruction is generated at the current feedback time node, the process includes:

[0044] Preset a first operation deviation value threshold D1 and a second operation deviation value threshold D2;

[0045] If d<D1, no correction instruction is generated at the current feedback time node;

[0046] If D1≤d<D2, the current feedback time node generates a first-level correction instruction;

[0047] If d ≥ D2, the current feedback time node generates a secondary correction instruction.

[0048] In some embodiments of the present application, the third processing module is further used to:

[0049] Establish multiple environmental characteristic indicators;

[0050] Generate the expected change curve of each environmental characteristic index in the current adjustment cycle;

[0051] Generate the fluctuation evaluation value f of the current adjustment period according to all expected change curves;

[0052]

[0053] Among them, e1 is the preset first weight coefficient; e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; θ is the number of environmental characteristic indicators; μi is the influencing factor of the i-th environmental characteristic indicator; ji is the reference value generated based on the expected change curve of the i-th environmental characteristic indicator in the current adjustment cycle; F' is the historical fluctuation reference value generated based on the environmental parameters of the previous adjustment cycle;

[0054] The time interval between adjacent monitoring time nodes in the current adjustment cycle is set according to the fluctuation evaluation value f.

[0055] In some embodiments of the present application, when determining whether to generate a secondary adjustment plan according to a preset monitoring time node, it includes:

[0056] Obtain the environmental parameters and operating parameters of the photovoltaic generator at the current monitoring time node;

[0057] Generate the power fluctuation value g of the current monitoring time node;

[0058] Preset a first power fluctuation value threshold G1;

[0059] If g>G1, a secondary adjustment plan is generated at the current monitoring time node, and the operating parameters of the secondary energy storage module are set according to the secondary adjustment plan.

[0060] In some embodiments of the present application, when generating the power fluctuation value g of the current monitoring time node, it includes:

[0061]

[0062] Among them, e5 is the preset fifth weight coefficient; e6 is the preset sixth weight coefficient; Q5 is the preset fifth fixed coefficient; Q6 is the preset sixth weight coefficient; hi is the real-time reference value of the i-th environmental characteristic indicator at the current monitoring time node; h'i is the expected reference value generated at the current monitoring time node based on the expected change curve of the i-th environmental characteristic indicator in the current adjustment cycle; Ki is the real-time power value of the photovoltaic generator at the current monitoring time node; K'i is the expected power value of the real-time power value of the photovoltaic generator at the current monitoring time node.

[0063] Compared with the prior art, the energy storage-assisted frequency and voltage regulation system of the embodiment of the present application has the following beneficial effects:

[0064] By adding a primary energy storage module (i.e., battery), multiple time intervals are established in a single regulation cycle through the predicted expected power curve, so as to set the sub-regulation strategy in each time interval according to the real-time status of the primary energy storage module, and perform auxiliary frequency and voltage regulation on the photovoltaic generator in a single regulation cycle to ensure the stable operation of the photovoltaic system, reduce the loss of a single energy storage module caused by overcharging or over-discharging problems, and increase the operating life of the energy storage module.

[0065] A secondary energy storage module (i.e., supercapacitor) is added, and multiple monitoring time nodes are set according to the fluctuation evaluation value within a single cycle. The real-time power of the photovoltaic generator is monitored, abnormal power fluctuations are warned in time, and a rapid response is made through the secondary energy storage module to improve the efficiency of auxiliary frequency and voltage regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 It is a structural schematic diagram of an energy storage assisted frequency and voltage regulation system in a preferred embodiment of the present application. DETAILED DESCRIPTION

[0067] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0068] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, 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 should not be understood as a limitation on the present application.

[0069] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0070] In the description of this 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 the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0071] like Figure 1 As shown, an energy storage assisted frequency and voltage regulation system according to a preferred embodiment of the present application includes:

[0072] A prediction unit, used to establish multiple regulation cycles and generate an expected power curve in each regulation cycle according to a preset power prediction model;

[0073] An energy storage unit, comprising a plurality of primary energy storage modules and a single secondary energy storage module;

[0074] A monitoring unit, used to obtain operating parameters of the photovoltaic generator and status parameters of the energy storage unit;

[0075] The central control unit is used to sequentially generate the regulation plan within each regulation cycle and set the operating parameters of the energy storage unit according to the regulation plan.

[0076] Specifically, the central control unit includes:

[0077] The first processing module is used to establish a primary energy storage module sequence A, A = (a1, a2 ... ai ... an), where ai is the i-th primary energy storage module and n is the number of primary energy storage modules;

[0078] A second processing module is used to set a primary regulation plan for the current cycle according to the power prediction curve of the current regulation cycle, and set operating parameters of each primary energy storage module according to the primary regulation plan;

[0079] The third processing module is used to generate a fluctuation evaluation value of the current adjustment period and set a plurality of monitoring time nodes according to the fluctuation evaluation value;

[0080] The third processing module is also used to determine whether to generate a secondary adjustment plan based on a preset monitoring time node.

[0081] Specifically, the primary energy storage module is preferably a battery, and the secondary energy storage module is preferably a supercapacitor.

[0082] Specifically, the monitoring unit includes multiple monitoring sub-modules, which are arranged at the photovoltaic generator, the secondary energy storage module and each primary energy storage module, and are used to collect the real-time power generation power of the photovoltaic generator and the real-time status parameters of each primary energy storage module and the secondary energy storage module.

[0083] Specifically, the prediction unit establishes a power prediction model according to the historical operating parameters of the photovoltaic generator.

[0084] Specifically, the adjustment cycle is preferably one day, and the duration of the adjustment cycle can be set according to historical operating parameters.

[0085] In a preferred embodiment of the present application, the second processing module is also used for:

[0086] Generate multiple time intervals according to the power prediction curve of the current regulation cycle;

[0087] Establish a time interval sequence T, T = (t1, t2...ti...tn), where ti is the i-th time interval in the current adjustment cycle; n is the number of time intervals in the current adjustment cycle;

[0088] According to the time interval sequence T, the i-th time interval is sequentially set as the target time interval;

[0089] Generate an expected remaining power sequence C within the target time interval according to the preset simulation model, C = (c1, c2...ci...cm), where ci is the expected remaining power of the i-th primary energy storage module at the start time node of the target time interval;

[0090] Obtaining the expected power sub-curve within the target time interval;

[0091] Generate a sub-regulation strategy for the target time interval according to the expected power sub-curve and the expected remaining power sequence C;

[0092] Generate sub-regulation strategies for each time interval in turn;

[0093] Generate a first-level adjustment plan for the current adjustment cycle based on all sub-adjustment strategies.

[0094] Specifically, the charging time period, discharging time period and non-regulation time period of the energy storage system are determined according to the power forecast curve in the current regulation cycle and the demand parameters of the power grid. Thus, multiple time intervals are constructed; the energy storage system in any two adjacent time intervals is in different operating states.

[0095] Specifically, the operating status of each primary energy storage module is simulated by a preset simulation model, and the expected remaining power sequence C within the target time interval is generated according to the sub-regulation strategy of the previous time interval and the expected remaining power of each primary energy storage module at the start time node of the previous time interval.

[0096] Specifically, when generating a sub-adjustment strategy for a target time interval, it includes:

[0097] A first power threshold C1 and a second power threshold C2 are preset, and C1<C2;

[0098] generating a regulation mode for the target time interval according to the expected power sub-curve for the target time interval;

[0099] When the target time interval is in the first-level adjustment mode;

[0100] If ci<C1, the i-th primary energy storage module is eliminated in the target time interval;

[0101] Generate a sub-regulation strategy for the target time interval according to the elimination result and the expected power sub-curve of the target time interval;

[0102] When the target time interval is in the secondary adjustment mode;

[0103] If ci>C2, the i-th primary energy storage module is eliminated in the target time interval;

[0104] A sub-regulation strategy for the target time interval is generated according to the elimination result and the expected power sub-curve of the target time interval.

[0105] Specifically, the first power threshold refers to the minimum safe power of the first-level energy storage module, and the second power threshold refers to the maximum safe power of the first-level energy storage module. The first power threshold and the second power threshold can be set according to historical parameters.

[0106] Specifically, the first-level regulation mode indicates that the current energy storage system needs to complete the auxiliary frequency and voltage regulation of the photovoltaic generator through discharge. At this time, the first-level energy storage modules with expected remaining power less than the first power threshold are eliminated to avoid excessive discharge of the first-level energy storage modules. At the same time, the remaining first-level energy storage modules are regulated by average discharge to reduce the complexity of coordinated control and improve the efficiency of auxiliary frequency and voltage regulation.

[0107] Specifically, the secondary regulation mode indicates that the current energy storage system needs to complete the auxiliary frequency and voltage regulation of photovoltaic power generation through charging. At this time, the primary energy storage modules with expected remaining power higher than the second power threshold are eliminated to avoid overcharging of the primary energy storage modules. At the same time, the remaining primary energy storage modules are regulated by average charging to reduce the complexity of coordinated control and improve the efficiency of auxiliary frequency and voltage regulation.

[0108] It can be understood that in the above embodiment, a primary energy storage module (i.e., a battery) is added, and multiple time intervals are established in a single regulation cycle through the predicted expected power curve, so that the sub-regulation strategy in each time interval is set according to the real-time status of the primary energy storage module, and the photovoltaic generator in a single regulation cycle is assisted in frequency and voltage regulation to ensure the stable operation of the photovoltaic system, reduce the loss of a single energy storage module caused by overcharging or over-discharging problems, and increase the operating life of the energy storage module.

[0109] In a preferred embodiment of the present application, the central control unit further includes:

[0110] A correction module, used to obtain a time interval sequence T according to the current adjustment cycle;

[0111] Set the start time node of each time interval as the feedback time node;

[0112] Obtain the state parameters of each primary energy storage module and the operating parameters of the photovoltaic generator at the current feedback time node;

[0113] Generate an operation deviation value d of the current feedback time node, and determine whether to generate a correction instruction at the current feedback time node based on the operation deviation value d.

[0114] Specifically, the real-time remaining power of each primary energy storage module is generated according to the state parameters, and the actual power curve of the previous time interval is generated according to the operating parameters of the photovoltaic generator.

[0115] Specifically, when generating the running deviation value d of the current feedback time node, it includes:

[0116]

[0117] Among them, e3 is the preset third weight coefficient; e4 is the preset fourth weight coefficient; Q3 is the preset third fixed coefficient; Q4 is the preset fourth fixed coefficient; c 1i is the real-time remaining power of the i-th primary energy storage module at the current feedback time node; c' i is the expected remaining power of the i-th primary energy storage module at the current feedback time node; P is the deviation reference value set based on the overlap between the actual power curve and the expected power sub-curve of the photovoltaic generator in a time interval before the current feedback time node.

[0118] Specifically, all parameters in the model are normalized by presetting the third fixed coefficient and the fourth fixed coefficient, so that each parameter in each model is in the same value range.

[0119] Specifically, the larger the operating deviation value is, the lower the accuracy of the current auxiliary frequency and voltage regulation is.

[0120] Specifically, the lower the overlap between the actual power curve and the expected power sub-curve, the greater the corresponding deviation from the reference value.

[0121] Specifically, when judging whether a correction instruction is generated at the current feedback time node, it includes:

[0122] Preset a first operation deviation value threshold D1 and a second operation deviation value threshold D2;

[0123] If d<D1, no correction instruction is generated at the current feedback time node;

[0124] If D1≤d<D2, the current feedback time node generates a first-level correction instruction;

[0125] If d ≥ D2, the current feedback time node generates a secondary correction instruction.

[0126] Specifically, the first-level correction instruction refers to the need to correct the sub-regulation strategy of the current time interval according to the real-time status parameters of each first-level energy storage module, so as to ensure the efficiency of auxiliary frequency and voltage regulation and ensure the stable operation of the photovoltaic system.

[0127] Specifically, the secondary correction instruction means that the preset power prediction model needs to be corrected, thereby updating the expected power curve and correcting all remaining sub-regulation strategies in the current regulation cycle.

[0128] It can be understood that in the above embodiment, by establishing multiple feedback time nodes, the primary regulation strategy within a single regulation cycle is continuously corrected, thereby achieving precise control of the energy storage system, improving the efficiency of auxiliary frequency and voltage regulation, and ensuring the stable operation of the photovoltaic system.

[0129] In a preferred embodiment of the present application, the third processing module is also used for:

[0130] Establish multiple environmental characteristic indicators;

[0131] Generate the expected change curve of each environmental characteristic index in the current adjustment cycle;

[0132] Generate the fluctuation evaluation value f of the current adjustment period according to all expected change curves;

[0133]

[0134] Among them, e1 is the preset first weight coefficient; e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; θ is the number of environmental characteristic indicators; μi is the influencing factor of the i-th environmental characteristic indicator; ji is the reference value generated based on the expected change curve of the i-th environmental characteristic indicator in the current adjustment cycle; F' is the historical fluctuation reference value generated based on the environmental parameters of the previous adjustment cycle;

[0135] The time interval between adjacent monitoring time nodes in the current adjustment cycle is set according to the fluctuation evaluation value f.

[0136] Specifically, all parameters in the model are normalized by presetting the first fixed coefficient and the second fixed coefficient, so that each parameter in each model is in the same value range.

[0137] Specifically, the larger the fluctuation evaluation value, the greater the possibility of abnormal power fluctuation, and the smaller the time interval between the corresponding adjacent monitoring time nodes.

[0138] Specifically, environmental characteristic indicators include but are not limited to temperature, light intensity, cloud cover, humidity and other parameters that affect photovoltaic power generation.

[0139] Specifically, when determining whether to generate a secondary adjustment plan based on the preset monitoring time node, it includes:

[0140] Obtain the environmental parameters and operating parameters of the photovoltaic generator at the current monitoring time node;

[0141] Generate the power fluctuation value g of the current monitoring time node;

[0142] Preset a first power fluctuation value threshold G1;

[0143] If g>G1, a secondary adjustment plan is generated at the current monitoring time node, and the operating parameters of the secondary energy storage module are set according to the secondary adjustment plan.

[0144] Specifically, multiple monitoring time nodes are set according to the fluctuation evaluation value within a single cycle, the real-time power of the photovoltaic generator is monitored, abnormal power fluctuations are warned in time, and a rapid response is made through the secondary energy storage module to improve the efficiency of auxiliary frequency and voltage regulation.

[0145] Specifically, the operating parameters of the secondary energy storage module are set according to the real-time power change value to achieve rapid frequency and voltage regulation, so that the system voltage and frequency remain constant and prevent power quality problems caused by sudden load changes. Ensure that the power fluctuations of the photovoltaic generator caused by environmental changes do not affect the normal operation of the load.

[0146] Specifically, when generating the power fluctuation value g of the current monitoring time node, it includes:

[0147]

[0148] Among them, e5 is the preset fifth weight coefficient; e6 is the preset sixth weight coefficient; Q5 is the preset fifth fixed coefficient; Q6 is the preset sixth weight coefficient; hi is the real-time reference value of the i-th environmental characteristic indicator at the current monitoring time node; h'i is the expected reference value generated at the current monitoring time node based on the expected change curve of the i-th environmental characteristic indicator in the current adjustment cycle; Ki is the real-time power value of the photovoltaic generator at the current monitoring time node; K'i is the expected power value of the real-time power value of the photovoltaic generator at the current monitoring time node.

[0149] Specifically, all parameters in the model are normalized by presetting the fifth fixed coefficient and the sixth fixed coefficient, so that each parameter in each model is in the same value range.

[0150] Specifically, the larger the power fluctuation value is, the greater the possibility of abnormal power fluctuation at the current monitoring time node is.

[0151] According to the first concept of the present application, a primary energy storage module (i.e., a battery) is added, and multiple time intervals are established in a single regulation cycle through the predicted expected power curve, so that the sub-regulation strategy in each time interval is set according to the real-time status of the primary energy storage module, and the photovoltaic generator in a single regulation cycle is assisted in frequency and voltage regulation to ensure the stable operation of the photovoltaic system, reduce the loss of a single energy storage module caused by overcharging or over-discharging problems, and increase the operating life of the energy storage module.

[0152] According to the second concept of the present application, a secondary energy storage module (i.e., supercapacitor) is added, and multiple monitoring time nodes are set according to the fluctuation evaluation value within a single cycle, so as to monitor the real-time power of the photovoltaic generator, promptly issue an early warning for abnormal power fluctuations, and respond quickly through the secondary energy storage module to improve the efficiency of auxiliary frequency and voltage regulation.

[0153] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present application. These improvements and substitutions should also be regarded as the scope of protection of the present application.

Claims

1. An energy storage assisted frequency and voltage regulation system, characterized in that: include: A prediction unit, used to establish multiple regulation cycles and generate an expected power curve in each regulation cycle according to a preset power prediction model; An energy storage unit, comprising a plurality of primary energy storage modules and a single secondary energy storage module; A monitoring unit, used to obtain operating parameters of the photovoltaic generator and status parameters of the energy storage unit; The central control unit is used to sequentially generate the regulation plan within each regulation cycle and set the operating parameters of the energy storage unit according to the regulation plan.

2. The energy storage assisted frequency and voltage regulation system according to claim 1, characterized in that: The central control unit comprises: The first processing module is used to establish a primary energy storage module sequence A, where A=(a1, a2…ai…an), where ai is the i-th primary energy storage module and n is the number of primary energy storage modules; A second processing module is used to set a primary regulation plan for the current cycle according to a power prediction curve of the current regulation cycle, and to set operating parameters of each primary energy storage module according to the primary regulation plan; The third processing module is used to generate a fluctuation evaluation value of the current adjustment period and set a plurality of monitoring time nodes according to the fluctuation evaluation value; The third processing module is also used to determine whether to generate a secondary adjustment plan according to a preset monitoring time node.

3. The energy storage assisted frequency and voltage regulation system according to claim 2, characterized in that: The second processing module is also used for: Generate multiple time intervals according to the power prediction curve of the current regulation cycle; Establish a time interval sequence T, T = (t1, t2...ti...tn), where ti is the i-th time interval in the current adjustment cycle; n is the number of time intervals in the current adjustment cycle; According to the time interval sequence T, the i-th time interval is sequentially set as the target time interval; Generate an expected remaining power sequence C within the target time interval according to the preset simulation model, C = (c1, c2...ci...cm), where ci is the expected remaining power of the i-th primary energy storage module at the start time node of the target time interval; Obtaining the expected power sub-curve within the target time interval; Generate a sub-regulation strategy for the target time interval according to the expected power sub-curve and the expected remaining power sequence C; Generate sub-regulation strategies for each time interval in turn; Generate a first-level adjustment plan for the current adjustment cycle based on all sub-adjustment strategies.

4. The energy storage assisted frequency and voltage regulation system according to claim 3, characterized in that: The generation of the sub-adjustment strategy for the target time interval includes: A first power threshold C1 and a second power threshold C2 are preset, and C1<C2; generating a regulation mode for the target time interval according to the expected power sub-curve for the target time interval; When the target time interval is in the first-level adjustment mode; If ci<C1, the i-th primary energy storage module is eliminated in the target time interval; Generate a sub-regulation strategy for the target time interval according to the elimination result and the expected power sub-curve of the target time interval; When the target time interval is in the secondary adjustment mode; If ci>C2, the i-th primary energy storage module is eliminated in the target time interval; A sub-regulation strategy for the target time interval is generated according to the elimination result and the expected power sub-curve of the target time interval.

5. The energy storage assisted frequency and voltage regulation system according to claim 4, characterized in that: The central control unit also includes: A correction module, used to obtain a time interval sequence T according to the current adjustment cycle; Set the start time node of each time interval as the feedback time node; Obtain the state parameters of each primary energy storage module and the operating parameters of the photovoltaic generator at the current feedback time node; Generate an operation deviation value d of the current feedback time node, and determine whether to generate a correction instruction at the current feedback time node based on the operation deviation value d.

6. The energy storage assisted frequency and voltage regulation system according to claim 5, characterized in that: When generating the running deviation value d of the current feedback time node, it includes: Among them, e3 is the preset third weight coefficient; e4 is the preset fourth weight coefficient; Q3 is the preset third fixed coefficient; Q4 is the preset fourth fixed coefficient; c 1i is the real-time remaining power of the i-th primary energy storage module at the current feedback time node; c' i is the expected remaining power of the i-th primary energy storage module at the current feedback time node; P is the deviation reference value set based on the overlap between the actual power curve and the expected power sub-curve of the photovoltaic generator in a time interval before the current feedback time node.

7. The energy storage assisted frequency and voltage regulation system according to claim 6, characterized in that: When judging whether a correction instruction is generated at the current feedback time node, it includes: Preset a first operation deviation value threshold D1 and a second operation deviation value threshold D2; If d<D1, no correction instruction is generated at the current feedback time node; If D1≤d<D2, the current feedback time node generates a first-level correction instruction; If d ≥ D2, the current feedback time node generates a secondary correction instruction.

8. The energy storage assisted frequency and voltage regulation system according to claim 4, characterized in that: The third processing module is also used for: Establish multiple environmental characteristic indicators; Generate the expected change curve of each environmental characteristic index in the current adjustment cycle; Generate the fluctuation evaluation value f of the current adjustment period according to all expected change curves; Among them, e1 is the preset first weight coefficient; e2 is the preset second weight coefficient; Q1 is the preset first fixed coefficient; Q2 is the preset second fixed coefficient; θ is the number of environmental characteristic indicators; μi is the influencing factor of the i-th environmental characteristic indicator; ji is the reference value generated based on the expected change curve of the i-th environmental characteristic indicator in the current adjustment cycle; F' is the historical fluctuation reference value generated based on the environmental parameters of the previous adjustment cycle; The time interval between adjacent monitoring time nodes in the current adjustment cycle is set according to the fluctuation evaluation value f.

9. The energy storage-assisted frequency and voltage regulation system according to claim 8, characterized in that: When determining whether to generate a secondary adjustment plan based on the preset monitoring time node, it includes: Obtain the environmental parameters and operating parameters of the photovoltaic generator at the current monitoring time node; Generate the power fluctuation value g of the current monitoring time node; Preset a first power fluctuation value threshold G1; If g>G1, a secondary adjustment plan is generated at the current monitoring time node, and the operating parameters of the secondary energy storage module are set according to the secondary adjustment plan.

10. The energy storage-assisted frequency and voltage regulation system according to claim 9, characterized in that: When generating the power fluctuation value g of the current monitoring time node, it includes: Among them, e5 is the preset fifth weight coefficient; e6 is the preset sixth weight coefficient; Q5 is the preset fifth fixed coefficient; Q6 is the preset sixth weight coefficient; hi is the real-time reference value of the i-th environmental characteristic indicator at the current monitoring time node; h'i is the expected reference value generated at the current monitoring time node based on the expected change curve of the i-th environmental characteristic indicator in the current adjustment cycle; Ki is the real-time power value of the photovoltaic generator at the current monitoring time node; K'i is the expected power value of the real-time power value of the photovoltaic generator at the current monitoring time node.

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