Energy control method and device based on optical diesel storage micro-grid system, and medium

Abstract

The invention discloses an energy control method and device based on an optical diesel storage micro-grid system and a medium. The invention relates to the field of energy management, and solves the problem of consumption of diesel generator feedback residual electricity and photovoltaic feedback electricity in a factory and the problem of reducing the demand electric charge of the factory. Whether feedback electricity is generated or not is recognized through power grid home-entry load data, once it is judged that the feedback electricity exists and energy storage does not reach the preset upper limit, energy storage charging is immediately controlled, redundant electric energy such as the feedback electricity of the diesel generator test stand and photovoltaic residual electricity is stored, and the problems that the feedback electricity cannot be connected to a grid and consequently waste is caused and photovoltaic light is abandoned are solved; when no feedback electricity exists, whether the energy storage state of charge (SOC) is lower than a preset lower limit or not is judged to avoid over-discharge, then charging is triggered in combination with the conditions that the load power is smaller than or equal to a peak clipping threshold value in a low ebb period, and low-cost energy storage is conducted through the valley electricity; and when the load exceeds a peak clipping threshold value and is in a non-low-ebb period, discharging is triggered, and the load peak demand is matched. In addition, when the load peak or the load exceeds the peak clipping threshold value, power supply is supplemented through energy storage discharge, and the cost is reduced.

Description

Technical Field

[0001] This application relates to the field of energy management, and in particular to an energy control method, device and medium based on a photovoltaic-diesel-storage microgrid system. Background Technology

[0002] Currently, microgrid systems in industrial applications generally suffer from the randomness and volatility of distributed power sources (such as photovoltaic and diesel generators). This is particularly true for diesel generator R&D and manufacturing companies, where feedback energy is generated during diesel engine factory hot-testing (relying on electric dynamometers). Current mainstream microgrid system control strategies focus on absorbing surplus electricity from photovoltaic and wind power and on peak shaving and valley filling, neglecting the needs for diesel generator surplus electricity absorption and demand management. Furthermore, the electricity generated during testing cannot be stored or fed back into the municipal grid, resulting in energy waste.

[0003] Existing energy storage systems (such as battery cabinets) employ simple charging and discharging strategies, relying heavily on fixed time periods (such as peak-valley electricity price differences), and are unable to dynamically respond to load changes. This results in limited peak shaving and valley filling effects, and insufficient optimization of basic electricity costs.

[0004] Therefore, how to solve the problem of absorbing the surplus electricity from diesel generator feedback and photovoltaic feedback in the plant area and reduce the electricity demand cost in the plant area is a technical problem that urgently needs to be solved by people in this field. Summary of the Invention

[0005] The purpose of this application is to provide an energy control method, device and medium based on a photovoltaic-diesel-storage microgrid system to solve the problem of absorbing surplus electricity from diesel generator feedback and photovoltaic feedback in the plant area, as well as to reduce the demand electricity cost in the plant area.

[0006] To address the aforementioned technical problems, this application provides an energy control method based on a photovoltaic-diesel-storage microgrid system, comprising:

[0007] Based on the grid load data of the microgrid system, determine whether the microgrid generates feedback power.

[0008] If the feedback electricity is generated, it is determined whether the state of charge of the energy storage system has reached the preset upper limit.

[0009] If the preset upper limit is not reached, the energy storage system will be charged.

[0010] If the feedback power is not present, then determine whether the state of charge of the energy storage system is lower than a preset lower limit;

[0011] If the load is below the preset lower limit, and the current period is a low period and the load power is not greater than the preset peak shaving threshold, the energy storage system will be controlled to charge.

[0012] If the load power is not lower than the preset lower limit, the energy storage system will be controlled to discharge when the load power exceeds the preset peak shaving threshold or when the current period is not a low-valley period.

[0013] As an optional solution, in the above-mentioned energy control method based on a photovoltaic-diesel-storage microgrid system, the determination of whether the microgrid generates feedback power based on the grid load data of the microgrid system includes:

[0014] Real-time load power data at the grid access point is collected through the grid-connected cabinet meters or box-type substation meters of the microgrid system, serving as the grid access load data for households.

[0015] Collect the total real-time output power of distributed power sources within the microgrid, wherein the distributed power sources include at least photovoltaic modules and diesel generators;

[0016] If the total real-time output power is greater than the grid load power, then it is determined that the microgrid generates feedback power.

[0017] If the total real-time output power is not greater than the grid load power, then it is determined that the microgrid has not generated feedback power.

[0018] As an optional solution, in the above-mentioned energy control method based on a photovoltaic-diesel-storage microgrid system, the step of controlling the energy storage system to charge if the preset upper limit is not reached includes:

[0019] Obtain the feedback power and the rated power of the energy storage converter;

[0020] If the feedback power is greater than the rated power of the energy storage converter, then the charging power of the energy storage system is equal to the rated power of the energy storage converter.

[0021] If the feedback power is not greater than the rated power of the energy storage converter, then determine the charging power of the energy storage system relative to the feedback power.

[0022] The energy storage system is charged according to the charging power.

[0023] As an optional solution, in the above-mentioned energy control method based on photovoltaic-diesel-storage microgrid system, if the load is below a preset lower limit, and the current period is a low-load period and the load power is not greater than a preset peak-shaving threshold, the energy storage system is controlled to charge, including:

[0024] Determine whether the difference between the preset peak shaving threshold and the load power is greater than the rated power of the energy storage converter;

[0025] If not, then the charging power of the energy storage system is determined to be the difference between the peak-shaving power and the load power;

[0026] If so, then the charging power of the energy storage system is determined to be the rated power of the energy storage converter;

[0027] The energy storage system is charged according to the charging power until the state of charge of the energy storage system reaches a preset upper limit.

[0028] As an optional solution, in the above-mentioned energy control method based on photovoltaic-diesel-storage microgrid system, if the load power is not lower than a preset lower limit, the energy storage system is controlled to discharge when the load power exceeds a preset peak-shaving threshold or when the current period is a non-off-peak period, including:

[0029] If the load power exceeds the preset peak shaving threshold, determine whether the difference between the preset peak shaving threshold and the load power is greater than the rated power of the energy storage converter.

[0030] If not, then the discharge power of the energy storage system is determined to be the difference between the load power and the peak-shaving power;

[0031] If so, then the discharge power of the energy storage system is determined to be the rated power of the energy storage converter.

[0032] As an optional solution, in the above-mentioned energy control method based on photovoltaic-diesel-storage microgrid system, if the load is not lower than a preset lower limit, the energy storage system is controlled to discharge when the load power exceeds a preset peak-shaving threshold or during non-off-peak periods, including:

[0033] If the current period is not a low-peak period, determine whether the load power is greater than the rated power of the energy storage converter;

[0034] If not, then the discharge power of the energy storage system is determined to be the load power;

[0035] If so, then the discharge power of the energy storage system is determined to be the rated power of the energy storage converter.

[0036] As an optional solution, the energy control method based on the photovoltaic-diesel-storage microgrid system mentioned above also includes:

[0037] Monitor the connection status of the microgrid system with the mains power grid;

[0038] If a grid fault is detected, the microgrid will be switched to off-grid operation mode.

[0039] In off-grid mode, the control energy storage system and the energy storage converter form an independent power supply circuit to provide continuous power to the load equipment in the microgrid until the grid fault is cleared, the microgrid resumes grid-connected operation, or the state of charge of the energy storage system is lower than the safe operating threshold.

[0040] To address the aforementioned technical problems, this application also provides an energy control device based on a photovoltaic-diesel-storage microgrid system, comprising:

[0041] The surplus power judgment module is used to determine whether the microgrid generates feedback power based on the grid load data of the microgrid system; if so, it triggers the surplus power storage module; if not, it triggers the peak shaving and valley filling module.

[0042] The residual power storage module is used to determine whether the state of charge of the energy storage system has reached the preset upper limit; if not, it triggers the charging module.

[0043] The charging module is used to control the charging of the energy storage system;

[0044] The peak shaving and valley filling module is used to determine whether the state of charge of the energy storage system is lower than a preset lower limit; if so, the first management module is triggered, and if not, the second management module is triggered.

[0045] The first management module is used to control the energy storage system to charge when the current time period is a low-end period and the load power is not greater than the preset peak shaving threshold.

[0046] The second management module is used to control the energy storage system to discharge when the load power exceeds the preset peak shaving threshold or when the current period is not a low-peak period.

[0047] To address the aforementioned technical problems, this application also provides an energy control device based on a photovoltaic-diesel-storage microgrid system, comprising:

[0048] Memory, used to store computer programs;

[0049] A processor is used to implement the steps of the energy control method based on a photovoltaic-diesel-storage microgrid system described above when executing the computer program.

[0050] To address the aforementioned technical problems, this application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the energy control method based on a photovoltaic-diesel-storage microgrid system described above.

[0051] The energy control method based on a photovoltaic-diesel-storage microgrid system provided in this application identifies whether feedback power is generated through grid load data. Once feedback power is detected and the energy storage has not reached a preset upper limit, the energy storage is immediately charged to store redundant energy such as feedback power from the diesel generator test bench and surplus photovoltaic power, avoiding the waste of feedback power due to grid incompatibility and the problem of photovoltaic curtailment. When there is no feedback power, the system first checks whether the energy storage state of charge (SOC) is below a preset lower limit to avoid over-discharge, and then triggers charging based on off-peak hours and load power ≤ peak shaving threshold conditions to utilize off-peak electricity for low-cost energy storage. Discharge is triggered when the load exceeds the peak shaving threshold or during non-off-peak hours to match peak load demand. In addition, during peak load or when the load exceeds the peak shaving threshold, the energy storage is discharged to supplement power supply, reducing the peak power drawn by the factory from the grid, reducing demand electricity costs, and lowering costs.

[0052] In addition, this application also provides an apparatus and medium that correspond to the above-mentioned energy control method based on a photovoltaic-diesel-storage microgrid system, with the same effect. Attached Figure Description

[0053] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 A flowchart of an energy control method based on a photovoltaic-diesel-storage microgrid system is provided as an embodiment of this application;

[0055] Figure 2 A microgrid energy management system architecture diagram provided for embodiments of this application;

[0056] Figure 3 A structural diagram of an energy control device based on a photovoltaic-diesel-storage microgrid system provided in this application embodiment;

[0057] Figure 4 A structural diagram of another energy control device based on a photovoltaic-diesel-storage microgrid system provided in this application embodiment. Detailed Implementation

[0058] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this application.

[0059] The core of this application is to provide an energy control method, device, and medium based on a photovoltaic-diesel-storage microgrid system.

[0060] To enable those skilled in the art to better understand the present application, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] This application provides an energy control method based on a photovoltaic-diesel-storage microgrid system, such as... Figure 1 As shown, it includes:

[0062] S11: Based on the grid load data of the microgrid system, determine whether the microgrid generates feedback power;

[0063] S12: If feedback electricity is generated, determine whether the state of charge of the energy storage system has reached the preset upper limit;

[0064] S13: If the preset upper limit is not reached, control the energy storage system to charge;

[0065] S14: If there is no feedback power, determine whether the state of charge of the energy storage system is lower than the preset lower limit;

[0066] S15: If the load is below the preset lower limit, and the current period is a low period and the load power is not greater than the preset peak shaving threshold, control the energy storage system to charge.

[0067] S16: If the load power is not lower than the preset lower limit, the energy storage system will be controlled to discharge when the load power exceeds the preset peak shaving threshold or when the current period is not a low-valley period.

[0068] Household load data refers to real-time electricity load data at the connection point between the microgrid system and the mains power grid. It is generally obtained through data acquisition equipment such as grid-connected cabinet meters and transformer substation meters. It reflects the real-time power that the factory draws from or feeds back to the mains power and is the core basis for judging the energy exchange status between the microgrid and the mains power.

[0069] Feedback power refers to the redundant power generated when the total real-time output of distributed power sources (including at least photovoltaic modules and diesel generators, of which diesel generators include test bench dynamometers and emergency units) in a microgrid exceeds the total real-time power demand of the load end (the cluster of electrical equipment in the factory). Specifically, it includes surplus photovoltaic power (the portion of photovoltaic power generation that exceeds the immediate load) and feedback power generated by the operation of the diesel engine test bench dynamometer (power that cannot be connected to the grid during the test).

[0070] Step S11 is used to identify whether there is recyclable redundant electrical energy within the microgrid. It should be noted that, due to the randomness of photovoltaic output within the microgrid affected by weather and the intermittent operation of the diesel generator test bench, the generation of feedback power is not continuous. Therefore, it is necessary to correlate distributed power generation output with grid load data to accurately determine whether feedback power is generated.

[0071] If feedback power is generated in step S12, it is determined whether the state of charge (SOC) of the energy storage system has reached the preset upper limit. The SOC of the energy storage system refers to the percentage of the total capacity of the energy storage system with its current remaining power. The purpose of the preset upper limit is to avoid overcharging of the energy storage system (preventing battery damage and extending cycle life). Generally, it refers to SOC=95%, but the specific value can be adjusted according to the type of energy storage battery. This embodiment does not impose a strict limitation. It should be noted that even if the microgrid generates feedback power, if the energy storage system is already fully charged (SOC reaches the preset upper limit), continuing to charge will lead to battery overheating and shortened lifespan. Therefore, the SOC state must be determined first. If the SOC has not reached the preset upper limit, the charging process begins; if the upper limit has been reached, the process terminates.

[0072] If step S13 does not reach the preset upper limit, the energy storage system is charged to store the redundant feedback power, thus avoiding energy waste. It should be noted that this step does not mean the charging power is unlimited. The charging power must be determined based on the relationship between the feedback power and the rated power of the energy storage converter (PCS). If the feedback power > the rated power of the PCS, the PCS is charged at its rated power (to prevent PCS overload); if the feedback power ≤ the rated power of the PCS, the feedback power is used to charge (maximizing the utilization of surplus power). Furthermore, this addresses the pain points of diesel generator feedback power not being able to be stored and photovoltaic curtailment, thereby improving energy utilization efficiency.

[0073] If there is no feedback power in step S14, then it is determined whether the state of charge (SOC) of the energy storage system is below a preset lower limit. The purpose of the preset lower limit is to prevent the energy storage system from being over-discharged (to prevent performance degradation caused by deep battery discharge). Generally, it refers to SOC=5%, which is similar to the preset upper limit. The specific value can be adjusted according to the battery characteristics. When there is no feedback power, the microgrid may be in a state of "load demand > distributed power output", and it needs to rely on energy storage discharge to supplement power supply. However, the prerequisite for energy storage discharge is that there is sufficient power. Therefore, it is necessary to first determine whether the SOC is below the preset lower limit. If it is below the lower limit, continuing to discharge will damage the battery.

[0074] If step S15 is below the preset lower limit, and the current time period is a low-peak period and the load power is not greater than the preset peak shaving threshold, the control system will start charging. The low-peak period generally refers to 0-8 am, when the grid electricity price is lower (valley electricity), making it the best time for low-cost energy storage. The specific time period can be adjusted according to the local grid electricity price policy. Load power: refers to the real-time power consumption of the load end within the microgrid (such as the total power of factory production equipment and test benches), which is related to the grid's incoming load data and reflects the electricity demand within the microgrid. The preset peak shaving threshold is a critical value set to control the peak grid power consumption. If the load power exceeds this threshold, it will lead to an increase in demand charge (basic electricity charge). The specific value needs to be set according to the factory's historical load data and the grid demand standard. In the charging control loop under the scenario of no feedback power and low SOC, low-cost off-peak electricity is used to supplement the energy storage capacity, while avoiding increasing the peak grid load during the charging process.

[0075] It should be noted that this step sets two additional conditions: off-peak hours and load power ≤ peak shaving threshold. The reason is that the grid electricity price is low during off-peak hours, and charging at this time can reduce the cost of energy storage. When the load power ≤ peak shaving threshold, the grid power supply pressure is small, and charging will not lead to an increase in peak power (avoiding an increase in demand electricity costs). Similarly, if the current period is not an off-peak period or the load power is > peak shaving threshold, charging will not be started to prevent cost increases or demand electricity costs from increasing. That is, step S16: if it is not lower than the preset lower limit, the energy storage system will be controlled to discharge when the load power exceeds the preset peak shaving threshold or the current period is a non-off-peak period.

[0076] At this time, energy storage discharge is used to supplement power supply, reducing the peak power drawn by the factory from the grid and reducing demand electricity costs; by replacing grid power with energy storage discharge, load demand can be met and peak-valley arbitrage profits can be obtained; in addition, this step does not mean that the discharge power is unlimited. In fact, the discharge power needs to be determined based on the difference between the load power and the peak shaving threshold and the rated power of the PCS to prevent PCS overload.

[0077] The energy control method based on a photovoltaic-diesel-storage microgrid system provided in this application identifies whether feedback power is generated through grid load data. Once feedback power is detected and the energy storage has not reached a preset upper limit, the energy storage is immediately charged to store redundant energy such as feedback power from the diesel generator test bench and surplus photovoltaic power, avoiding the waste of feedback power due to grid incompatibility and the problem of photovoltaic curtailment. When there is no feedback power, the system first checks whether the energy storage state of charge (SOC) is below a preset lower limit to avoid over-discharge, and then triggers charging based on off-peak hours and load power ≤ peak shaving threshold conditions to utilize off-peak electricity for low-cost energy storage. Discharge is triggered when the load exceeds the peak shaving threshold or during non-off-peak hours to match peak load demand. In addition, during peak load or when the load exceeds the peak shaving threshold, the energy storage is discharged to supplement power supply, reducing the peak power drawn by the factory from the grid, reducing demand electricity costs, and lowering costs.

[0078] According to the above embodiments, in a further specific embodiment, determining whether the microgrid generates feedback power based on the grid load data of the microgrid system includes:

[0079] Real-time load power data at the grid access point is collected through the grid-connected cabinet meters or box-type substation meters of the microgrid system, serving as the grid access load data for households.

[0080] Collect the total real-time output power of distributed power sources within the microgrid, which includes at least photovoltaic modules and diesel generators;

[0081] If the total real-time output power is greater than the grid load power, it is determined that the microgrid generates feedback power.

[0082] If the total real-time output power is not greater than the grid load power, it is determined that the microgrid has not generated feedback power.

[0083] Real-time load power of the power grid entering the household is collected through grid-connected cabinet meters or box-type substation meters. Figure 2 A microgrid energy management system architecture diagram is provided for embodiments of this application, such as... Figure 2 As shown, data is collected through electricity meter 1. In practice, the real-time data from the above-mentioned electricity meter can be read through the control layer of the smart microgrid energy management system (EMS) using the RS485 communication protocol. The collected data is the grid-connected load power. Other electricity meters 2-7 are used to collect the photovoltaic output power; 611 busbar power; energy storage system power; diesel generator output power; off-grid emergency unit output power; and equipment load power, respectively.

[0084] To collect the total real-time output power of distributed power sources within a microgrid, it is necessary to collect the power of photovoltaic modules and diesel generators. Total real-time output of distributed power sources = Total real-time output of photovoltaic modules + Real-time output of the diesel generator test bench.

[0085] Since the feedback power generated by the diesel generator test bench is not allowed to be fed back to the municipal power grid, if the total real-time output power is greater than the grid load power, the excess part is the feedback power (including surplus photovoltaic power and redundant power from the diesel generator test bench). In this case, it must be absorbed through the energy storage system and cannot be connected to the grid. If the total real-time output power is less than or equal to the grid load power, it means that the output of the distributed power source cannot meet the load demand, and it is necessary to supplement the power supply from the municipal power grid or start the energy storage discharge.

[0086] According to the above embodiments, in a further specific embodiment, if the preset upper limit is not reached, the energy storage system is controlled to charge, including:

[0087] Obtain the feedback power and the rated power of the energy storage converter;

[0088] If the feedback power is greater than the rated power of the energy storage converter, then the charging power of the energy storage system is equal to the rated power of the energy storage converter.

[0089] If the feedback power is not greater than the rated power of the energy storage converter, then determine the charging power of the energy storage system relative to the feedback power.

[0090] The energy storage system is charged according to the charging power.

[0091] The feedback power needs to be calculated based on the difference between the total real-time output of distributed power sources within the microgrid and the power of the grid-connected household load, reflecting the redundant energy available for charging. The PCS rated power serves as the upper limit of the core interface power connecting the energy storage system to the power source / grid, constraining the charging power and ensuring that the charging process does not exceed the hardware capacity of the equipment. The combination of these two factors avoids the problems of equipment overload caused by charging only according to the feedback power demand or the waste of redundant energy caused by charging only according to the PCS rated power.

[0092] When the feedback power exceeds the PCS rated power, directly charging at the feedback power will cause the PCS to operate under overload for a long time, leading to overheating, shortened lifespan, or even failure and shutdown. Therefore, the charging power must be limited to the PCS rated power.

[0093] When the feedback power is less than or equal to the PCS rated power, the PCS has the ability to fully absorb the feedback power. By setting the charging power to the feedback power, 100% of the redundant power can be stored, avoiding the problem of waste due to the inability of the feedback power to be connected to the grid. At the same time, there is no need to occupy the PCS redundant capacity, thus improving the utilization efficiency of the equipment.

[0094] This embodiment effectively avoids the risk of equipment overload caused by feedback power fluctuations (such as a sudden increase in the output of distributed power sources or a sudden drop in load demand) by rigidly constraining the rated power of the PCS, reducing the number of PCS failures and the probability of battery overcharging damage, extending the overall service life of the energy storage system, and reducing the economic cost of equipment replacement and maintenance.

[0095] According to the above embodiments, in a further specific embodiment, if the load is below a preset lower limit, and the current time period is a low-load period and the load power is not greater than a preset peak-shaving threshold, the energy storage system is controlled to charge, including:

[0096] Determine whether the difference between the preset peak shaving threshold and the load power is greater than the rated power of the energy storage converter;

[0097] If not, then the charging power of the energy storage system is determined to be the difference between the peak-shaving power and the load power;

[0098] If so, then the charging power of the energy storage system is determined to be the rated power of the energy storage converter;

[0099] The energy storage system is charged according to the charging power until the state of charge of the energy storage system reaches the preset upper limit.

[0100] The preset peak shaving threshold is set based on the factory's historical load data and the grid demand electricity price standard. It is a critical value for controlling the peak power taken from the grid and is directly related to electricity costs. The difference between the load power and the peak shaving threshold represents the redundant power space of the grid power supply capacity during off-peak periods (that is, the maximum safe power that can be used for energy storage charging without causing the grid peak to exceed the standard), which is the upper limit of the charging power. The rated power of the PCS energy storage system is the upper limit of the hardware power for charging, so as to avoid the charging power exceeding the equipment's carrying capacity.

[0101] If the difference is less than or equal to the rated power of the PCS, the redundant power space of the mains power does not exceed the carrying capacity of the PCS hardware. Setting the charging power to the peak shaving threshold load power can make full use of the cheap off-peak electricity during the off-peak hours of the mains power (such as off-peak electricity from 0-8 o'clock). Without increasing the peak load of the mains power (avoiding the increase in demand electricity costs), the energy storage capacity can be maximized, while avoiding the idleness of PCS resources.

[0102] If the difference is greater than the PCS's rated power, charging at the difference will cause the PCS to overload (causing equipment failure and shortening its lifespan). Therefore, the charging power should be limited to the PCS's rated power. While ensuring hardware safety, we should make the most of off-peak hours for charging to balance the relationship between "energy storage efficiency" and "equipment protection".

[0103] This embodiment ensures that energy storage charging during off-peak hours will not cause the mains power peak to exceed the limit by constraining the difference between the peak load power and the peak load power, thus avoiding the increase in demand-based electricity costs caused by charging.

[0104] According to the above embodiments, in a further specific embodiment, if the load is not lower than a preset lower limit, the energy storage system is controlled to discharge when the load power exceeds a preset peak-shaving threshold or the current time period is a non-off-peak period, including:

[0105] If the load power exceeds the preset peak shaving threshold, determine whether the difference between the preset peak shaving threshold and the load power is greater than the rated power of the energy storage converter.

[0106] If not, then the discharge power of the energy storage system is determined to be the difference between the load power and the peak-shaving power;

[0107] If so, then the discharge power of the energy storage system is determined to be the rated power of the energy storage converter.

[0108] The difference between the load power and the peak shaving threshold represents the portion of the load demand that exceeds the upper limit of the mains power peak control, and is also the target power that the energy storage system needs to supplement.

[0109] If the difference is less than or equal to the rated power of PCS, the hardware discharge capacity of the energy storage system can fully cover the supplementary demand for load exceeding the threshold. Setting the discharge power to the preset peak shaving threshold of the load power can accurately offset the load exceeding the upper limit of the mains power peak control, ensuring that the power taken by the factory from the mains power does not exceed the peak shaving threshold, thereby reducing electricity costs.

[0110] If the power difference is greater than the rated power of the PCS, discharging at the power difference will cause the PCS to overload (causing equipment overheating, shortening its lifespan, or even shutdown). Therefore, the discharge power should be limited to the rated power of the PCS. While ensuring hardware safety, the peak shaving effect of energy storage should be maximized. Although it cannot completely offset the over-threshold load, it can reduce the peak power drawn from the mains and reduce some demand electricity costs.

[0111] This embodiment ensures that energy storage discharge directly acts on the critical link where the load exceeds the threshold by using differential matching discharge power, thus avoiding the problems of "insufficient peak shaving (limited cost reduction in demand electricity)" or "excessive discharge (waste of energy storage power)" caused by traditional fixed power discharge.

[0112] According to the above embodiments, in a further specific embodiment, if the load is not lower than a preset lower limit, the energy storage system is controlled to discharge when the load power exceeds a preset peak shaving threshold or during non-off-peak periods, including:

[0113] If the current period is not a low-peak period, determine whether the load power is greater than the rated power of the energy storage converter;

[0114] If not, then the discharge power of the energy storage system is determined to be the load power;

[0115] If so, then the discharge power of the energy storage system is determined to be the rated power of the energy storage converter.

[0116] Non-off-peak hours refer to the off-peak and peak hours (such as the peak hours from 11 to 17) other than off-peak hours (such as 0-8 o'clock). During these hours, the electricity price is higher and there may be peak load demand.

[0117] When the load power is less than or equal to the PCS rated power, the energy storage hardware discharge capacity can fully cover the load demand. By setting the discharge power to the load power, the mains power supply (high-priced mains power during non-off-peak hours) can be completely replaced by energy storage discharge, maximizing the peak-valley arbitrage benefits while avoiding the waste of energy storage power.

[0118] If the load power is greater than the PCS rated power, discharging at the load power will cause the PCS to overload (causing equipment failure and shortening its lifespan). Therefore, the discharge power should be limited to the PCS rated power. On the basis of ensuring hardware safety, the mains power supply can be partially replaced by energy storage discharge (reducing the proportion of high-priced mains power consumption).

[0119] According to the above embodiments, in a further specific embodiment, it also includes:

[0120] Monitor the connection status of the microgrid system with the mains power grid;

[0121] If a grid fault is detected, the microgrid will be switched to off-grid operation mode.

[0122] In off-grid mode, the control energy storage system and the energy storage converter form an independent power supply circuit to provide continuous power to the load equipment in the microgrid until the grid fault is cleared, the microgrid resumes grid-connected operation, or the state of charge of the energy storage system is lower than the safe operating threshold.

[0123] The system collects parameters such as voltage, frequency, and current at the connection point between the microgrid and the mains power in real time. When the mains voltage exceeds the normal range (e.g., deviates from the rated voltage ±10%), the frequency is abnormal (e.g., deviates from 50Hz ±0.5Hz), or the current interruption lasts for more than a preset time (e.g., 0.5 seconds), it is determined to be a power grid fault, thus avoiding load power outages due to delayed fault identification.

[0124] After detecting a grid fault, the microgrid energy management system (EMS) immediately sends a switching command to the grid-connected circuit breaker and the energy storage converter (PCS) to disconnect the microgrid from the mains power (to prevent the fault from spreading to the mains power grid), and at the same time activates the PCS's off-grid operation mode.

[0125] The independent power supply circuit is powered by the energy storage system (lithium iron phosphate battery clusters). The DC power is converted into AC power (e.g., 380V / 220V) adapted to the load by the PCS, and then directly transmitted to the load equipment through the internal bus of the microgrid, forming an independent circuit of energy storage → PCS → load, which does not rely on the mains power. Priority is given to ensuring the power supply of critical loads (such as core equipment of diesel engine test benches and key equipment in factory production). The status of grid fault recovery is monitored in real time (e.g., mains voltage and frequency return to normal and remain stable for more than 30 seconds) and the state of charge (SOC) of the energy storage. When the grid fault is cleared, the microgrid is controlled to smoothly switch back to grid-connected mode. If the grid fault is not cleared but the energy storage SOC is below the safe operating threshold (e.g., 10%, to avoid battery over-discharge), the power supply to non-critical loads is gradually cut off according to load priority until only the most critical load is retained or the energy storage is depleted.

[0126] In the event of a grid failure, off-grid mode can prevent the entire microgrid from losing power. This is especially beneficial for diesel generator R&D and manufacturing companies. If core production processes such as diesel engine factory hot testing are interrupted, test data will be invalid and production schedules will be delayed. Off-grid mode ensures the continuous operation of core loads through independent power supply, significantly reducing economic losses caused by grid failures and lowering maintenance costs.

[0127] In the above embodiments, the energy control method based on the photovoltaic-diesel-storage microgrid system has been described in detail. This application also provides embodiments corresponding to the energy control device based on the photovoltaic-diesel-storage microgrid system. It should be noted that this application describes the embodiments of the device from two perspectives: one is based on the functional modules, and the other is based on the hardware.

[0128] From the perspective of functional modules Figure 3 A structural diagram of an energy control device based on a photovoltaic-diesel-storage microgrid system provided in this application embodiment is shown below. Figure 3 As shown, an energy control device based on a photovoltaic-diesel-storage microgrid system includes:

[0129] The surplus power judgment module 21 is used to determine whether the microgrid generates feedback power based on the grid load data of the microgrid system; if so, it triggers the surplus power storage module 22; if not, it triggers the peak shaving and valley filling module 24.

[0130] The residual power storage module 22 is used to determine whether the state of charge of the energy storage system has reached the preset upper limit; if not, the charging module 23 is triggered.

[0131] Charging module 23 is used to control the charging of the energy storage system;

[0132] Peak shaving and valley filling module 24 is used to determine whether the state of charge of the energy storage system is lower than a preset lower limit; if so, the first management module 25 is triggered, and if not, the second management module 26 is triggered.

[0133] The first management module 25 is used to control the energy storage system to charge when the current time period is a low-end period and the load power is not greater than the preset peak shaving threshold.

[0134] The second management module 26 is used to control the energy storage system to discharge when the load power exceeds the preset peak shaving threshold or when the current period is a non-off-peak period.

[0135] Since the embodiments of the apparatus and the embodiments of the method correspond to each other, please refer to the description of the embodiments of the method for the embodiments of the apparatus, which will not be repeated here.

[0136] Figure 4 A structural diagram of another energy control device based on a photovoltaic-diesel-storage microgrid system provided in this application embodiment is shown below. Figure 4 As shown, the energy control device based on the photovoltaic-diesel-storage microgrid system includes: a memory 30 for storing computer programs;

[0137] The processor 31 is used to execute a computer program to implement the steps of the method for obtaining user operation habit information as described in the above embodiment (energy control method based on photovoltaic-diesel-storage microgrid system).

[0138] The energy control device based on the photovoltaic-diesel-storage microgrid system provided in this embodiment may include, but is not limited to, mobile terminals, personal computers, workstations, etc.

[0139] The processor 31 may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor 31 may be implemented using at least one of the following hardware forms: Digital Signal Processor (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 31 may also include a main processor and a coprocessor. The main processor, also known as the Central Processing Unit (CPU), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, the processor 31 may integrate a Graphics Processing Unit (GPU), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, the processor 31 may also include an Artificial Intelligence (AI) processor, which handles computational operations related to machine learning.

[0140] The memory 30 may include one or more computer-readable storage media, which may be non-transitory. The memory 30 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In this embodiment, the memory 30 is used to store at least the following computer program 301, which, after being loaded and executed by the processor 31, is capable of implementing the relevant steps of the energy control method based on the photovoltaic-diesel-storage microgrid system disclosed in any of the foregoing embodiments. In addition, the resources stored in the memory 30 may also include an operating system 302 and data 303, and the storage method may be temporary or permanent storage. The operating system 302 may include Windows, Unix, Linux, etc. The data 303 may include, but is not limited to, data involved in implementing the energy control method based on the photovoltaic-diesel-storage microgrid system.

[0141] In some embodiments, the energy control device based on the photovoltaic-diesel-storage microgrid system may further include a display screen 32, an input / output interface 33, a communication interface 34, a power supply 35, and a communication bus 36.

[0142] Those skilled in the art will understand that Figure 4 The structure shown does not constitute a limitation on the energy control device based on the photovoltaic-diesel-storage microgrid system and may include more or fewer components than shown.

[0143] The energy control device based on a photovoltaic-diesel-storage microgrid system provided in this application includes a memory and a processor. When the processor executes the program stored in the memory, it can implement the following method: an energy control method based on a photovoltaic-diesel-storage microgrid system.

[0144] Finally, this application also provides an embodiment corresponding to a computer-readable storage medium. The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps described in the above embodiment of the energy control method based on a photovoltaic-diesel-storage microgrid system.

[0145] It is understood that if the methods in the above embodiments are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and executes all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0146] The computer-readable storage medium provided in this embodiment stores a computer program. When the processor executes the program, it can implement the following method: an energy control method based on a photovoltaic-diesel-storage microgrid system.

[0147] The energy control method, apparatus, and medium based on a photovoltaic-diesel-storage microgrid system provided in this application have been described in detail above. The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0148] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. An energy control method based on an optical storage micro-grid system, characterized in that, The method comprises the following steps: judging whether the micro-grid generates feedback power based on the grid household load data of the micro-grid system; if the feedback power is generated, judging whether the state of charge of the energy storage system reaches the preset upper limit; if the preset upper limit is not reached, controlling the energy storage system to charge; if the feedback power is not generated, judging whether the state of charge of the energy storage system is lower than the preset lower limit; if the state of charge is lower than the preset lower limit, and the current period is a valley period and the load power is not greater than the preset peak shaving threshold, controlling the energy storage system to charge; if the state of charge is not lower than the preset lower limit, controlling the energy storage system to discharge when the load power is greater than the preset peak shaving threshold or the current period is a non-valley period. 2.The energy control method based on the optical storage battery micro-grid system according to claim 1, wherein, The method of judging whether the micro-grid generates feedback power based on the grid household load data of the micro-grid system comprises the following steps: collecting real-time load power data of the grid household end through the grid-connected cabinet meter or the box transformer meter of the micro-grid system as the grid household load data; collecting the total real-time output power of the distributed power sources in the micro-grid, wherein the distributed power sources at least include photovoltaic components and diesel generators; if the total real-time output power is greater than the grid household load power, it is determined that the micro-grid generates feedback power; if the total real-time output power is not greater than the grid household load power, it is determined that the micro-grid does not generate feedback power. 3.The energy control method based on the optical battery micro-grid system according to claim 1, wherein, The method of controlling the energy storage system to charge when the preset upper limit is not reached comprises the following steps: obtaining feedback power and energy storage converter rated power; if the feedback power is greater than the energy storage converter rated power, determining that the charging power of the energy storage system is equal to the energy storage converter rated power; if the feedback power is not greater than the energy storage converter rated power, determining that the charging power of the energy storage system is for the feedback power; controlling the energy storage system to charge according to the charging power. 4.The energy control method based on the optical storage battery micro-grid system according to claim 1, wherein, The method of controlling the energy storage system to charge when the state of charge is lower than the preset lower limit, and the current period is a valley period and the load power is not greater than the preset peak shaving threshold comprises the following steps: judging whether the difference between the preset peak shaving threshold and the load power is greater than the energy storage converter rated power; if not, determining that the charging power of the energy storage system is the difference between the peak shaving power and the load power; if yes, determining that the charging power of the energy storage system is the energy storage converter rated power; controlling the energy storage system to charge according to the charging power until the state of charge of the energy storage system reaches the preset upper limit. 5.The energy control method based on the optical battery micro-grid system according to claim 1, wherein, The method of controlling the energy storage system to discharge when the state of charge is not lower than the preset lower limit, and the load power is greater than the preset peak shaving threshold or the current period is a non-valley period comprises the following steps: if the load power is greater than the preset peak shaving threshold, judging whether the difference between the preset peak shaving threshold and the load power is greater than the energy storage converter rated power; if not, determining that the discharging power of the energy storage system is the difference between the load power and the peak shaving power; if yes, determining that the discharging power of the energy storage system is the energy storage converter rated power. 6.The energy control method based on the optical storage battery micro-grid system according to claim 4, characterized in that, The method of controlling the energy storage system to discharge when the state of charge is not lower than the preset lower limit, and the load power is greater than the preset peak shaving threshold or the current period is a non-valley period comprises the following steps: if the current period is a non-valley period, judging whether the load power is greater than the energy storage converter rated power; if not, determining that the discharging power of the energy storage system is the load power; if yes, determining that the discharging power of the energy storage system is the energy storage converter rated power. 7.The energy control method based on the optical storage micro-grid system according to any one of claims 1 to 6, characterized in that, The method further comprises the following steps: monitoring the connection state of the micro-grid system and the municipal power grid; If a power grid fault is monitored, the micro-grid is controlled to switch to an off-grid operation mode; In the off-grid mode, the energy storage system and the energy storage converter form an independent power supply circuit to provide continuous power for the load devices in the micro-grid until the power grid fault is eliminated, the micro-grid resumes grid-connected operation, or the state of charge of the energy storage system is lower than a safe operation threshold.

8. An energy control device based on a light storage micro-grid system, characterized in that, Comprise: a residual power judgment module for judging whether the micro-grid generates feedback power based on the power grid household load data of the micro-grid system; if yes, triggering a residual power storage module; if no, triggering a peak clipping and valley filling module; the residual power storage module for judging whether the state of charge of the energy storage system reaches a preset upper limit; if no, triggering a charging module; the charging module for controlling the charging of the energy storage system; the peak clipping and valley filling module for judging whether the state of charge of the energy storage system is lower than a preset lower limit; if yes, triggering a first management module, and if no, triggering a second management module; the first management module for controlling the charging of the energy storage system when the current period is a valley period and the load power is not greater than a preset peak clipping threshold; the second management module for controlling the discharging of the energy storage system when the load power exceeds the preset peak clipping threshold or the current period is a non-valley period.

9. An energy control device based on a light diesel storage micro-grid system, characterized in that, Comprise: a memory for storing a computer program; a processor for executing the computer program to realize the steps of the energy control method based on the optical-diesel-storage micro-grid system according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer program is stored on the computer readable storage medium, and the computer program is executed by the processor to realize the steps of the energy control method based on the optical-diesel-storage micro-grid system according to any one of claims 1 to 7.

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