Intelligent control system of DC microgrid based on time node

Abstract

The present invention discloses a time node-based DC microgrid intelligent control system, which relates to the technical field of DC microgrids and solves the problem that the control accuracy and response speed of the current DC microgrid control system are difficult to meet work requirements. The control system includes an energy storage monitoring module, an energy storage analysis module, an energy storage control terminal, a microgrid monitoring module and a power supply compensation module. The energy storage monitoring module is used to monitor the energy storage status of the energy storage battery group in real time, the energy storage analysis module is used to perform a comprehensive analysis of the battery status of the energy storage battery group, and the energy storage control terminal is used to instantly regulate the working status of the energy storage battery group. After the regulation is completed, the microgrid monitoring module is used to monitor the power transmission data of the DC microgrid in real time, and the power supply compensation module is used to perform a comprehensive analysis of the power supply situation of the DC microgrid. The present invention realizes intelligent power supply regulation of the DC microgrid while ensuring control accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field of direct current microgrids, and in particular to a direct current microgrid intelligent control system based on time nodes. Background Art

[0002] The DC microgrid includes an AC / DC power distribution system, a photovoltaic power generation system, a smart energy storage system, an AC / DC conversion system, and a microgrid energy management system. When connecting photovoltaic generators and diesel generators, a 0.4kV low-voltage access is adopted. During the day when there is sunlight, the photovoltaic system generates electricity to ensure the power consumption of the load, and the excess is used to charge the energy storage battery. When the battery is fully charged, the photovoltaic power generation is restricted to protect the power generation. The diesel generator is used as a supplementary energy source. At night, the battery energy storage system mainly supplies power to the load. When the battery power is insufficient, the diesel generator is used to supplement the power supply.

[0003] In the current technological context, DC microgrid control systems are used to dispatch energy across various power supply and consumption points within a microgrid. However, due to the complex and volatile operating conditions of DC microgrids, the control accuracy and response speed of existing control systems are difficult to meet the operational requirements of DC microgrids. Therefore, how to achieve intelligent power supply regulation in DC microgrids while ensuring control accuracy is a current challenge.

[0004] To this end, the present invention proposes a DC microgrid intelligent control system based on time nodes. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a DC microgrid intelligent control system based on time nodes.

[0006] The technical problems to be solved by the present invention are:

[0007] How to achieve intelligent power supply regulation of DC microgrid while ensuring control accuracy.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] A time-node-based DC microgrid intelligent control system, including an energy storage monitoring module, an energy storage analysis module, an energy storage control terminal, a microgrid monitoring module, a power supply compensation module, and a processor;

[0010] The energy storage monitoring module is used to monitor the energy storage status of the energy storage battery pack in real time, obtain the battery cell status data of the energy storage battery pack through monitoring and send it to the processor, and the processor sends the battery cell status data of the energy storage battery pack to the energy storage analysis module;

[0011] The energy storage analysis module is used to perform a comprehensive analysis on the battery status of the energy storage battery pack, and the analysis obtains the grouping results of the main battery pack, the backup battery pack or the abnormal battery cell group and sends them to the processor. The processor sends the grouping results of the main battery pack, the backup battery pack or the abnormal battery cell group to the energy storage control terminal; the energy storage control terminal is used to immediately adjust the working status of the energy storage battery pack;

[0012] After the control is completed, the microgrid monitoring module is used to monitor the power transmission data of the DC microgrid in real time and send the power transmission data of the DC microgrid to the processor, and the processor sends the power transmission data of the DC microgrid to the power supply compensation module;

[0013] The power supply compensation module is used to perform a comprehensive analysis of the power supply situation of the DC microgrid.

[0014] Furthermore, the cell status data includes the cell voltage, actual cell power and cell temperature of each single cell in the energy storage battery pack.

[0015] Furthermore, the analysis process of the energy storage analysis module is as follows:

[0016] Obtain the cell voltage of each single cell in the energy storage battery pack, and compare the cell voltage of each single cell with the critical voltage range of the corresponding specification one by one;

[0017] If the cell voltage of any single cell does not fall within the critical voltage range of the corresponding specification, the corresponding single cell will be marked as an abnormal cell, and the energy storage battery group to which the single cell belongs will be marked as a cell abnormal group;

[0018] If the cell voltages of the individual battery cells all belong to the critical voltage range of the corresponding specification, the cell temperature of the individual battery cells is obtained and compared with the critical temperature range of the corresponding specification.

[0019] Furthermore, the analysis process of the energy storage analysis module also includes:

[0020] If the cell temperature of any single cell does not fall within the critical temperature range of the corresponding specification, the corresponding single cell will be marked as an abnormal cell, and the energy storage battery group to which the single cell belongs will be marked as a cell abnormal group;

[0021] If the cell temperatures of all the single cells belong to the critical temperature range of the corresponding specifications, the corresponding energy storage battery pack will be marked as a battery pack to be sorted.

[0022] Furthermore, the analysis process of the energy storage analysis module also includes:

[0023] Obtain the cell voltage DYir, cell actual power DLir, and cell temperature DTir of each single cell in the energy storage battery pack marked as the battery pack to be sorted, where i is the sequence number of the energy storage battery pack, the upper limit of i is n, and the value of n is equal to the number of battery packs to be sorted, and r is the sequence number of the single cell, the upper limit of r is R, and the value of R is equal to the number of single cells in the energy storage battery pack;

[0024] The energy storage priority value YXi of each energy storage battery group in the battery group to be sorted is calculated according to the formula. The specific formula is as follows:

[0025]

[0026] Wherein, e is a natural constant, BY is the nominal voltage of a single cell, BT is the optimum operating temperature of a single cell, BL is the nominal capacity of a single cell, a1 is the voltage deviation weight, a2 is the temperature deviation weight, and a3 is the remaining energy storage capacity weight;

[0027] Comparing the energy storage priority value of each energy storage battery group in the battery group to be sorted with the energy storage priority interval;

[0028] If the energy storage priority value of the energy storage battery group belongs to the first energy storage priority interval, the corresponding energy storage battery group will be divided into the backup battery group; if the energy storage priority value of the energy storage battery group belongs to the second energy storage priority interval, the corresponding energy storage battery group will be divided into the main battery group; wherein, the values ​​of the first energy storage priority interval and the second energy storage priority interval are both greater than zero, and the values ​​of the first energy storage priority interval are both less than the values ​​of the second energy storage priority interval.

[0029] Furthermore, the working process of the energy storage control terminal is as follows:

[0030] When there is surplus photovoltaic power generation, power is supplied to the energy storage battery group marked as the main battery group. When all the energy storage battery groups in the main battery group are fully charged, power is switched to the backup battery group to continue supplying power.

[0031] When the energy storage battery pack is marked as an abnormal cell group, the main battery pack or spare battery pack is selected for replacement and staff are dispatched for inspection and maintenance.

[0032] Furthermore, the power transmission data includes the photovoltaic output power of the photovoltaic power generation equipment in the DC microgrid and the load power of the DC microgrid, as well as the battery output power and the remaining battery capacity of the energy storage battery pack.

[0033] Furthermore, the working process of the power supply compensation module is as follows:

[0034] Obtain the remaining capacity (SOC) of the energy storage battery pack in the DC microgrid, and compare the remaining capacity of the energy storage battery pack with the critical charge capacity (CL) and the critical discharge capacity (FL).

[0035] If the remaining capacity of the energy storage battery pack is greater than or equal to the critical charge capacity, the energy storage battery pack switches to the discharge preparation mode, that is, the battery output power of the energy storage battery pack is greater than zero;

[0036] If the remaining capacity of the energy storage battery pack is less than the critical charge capacity and greater than or equal to the critical discharge capacity, the energy storage battery pack switches to free mode, that is, the energy storage battery pack can flexibly switch between charging and discharging;

[0037] If the remaining capacity of the energy storage battery pack is less than the critical discharge capacity, the energy storage battery pack switches to the charging preparation mode, that is, the battery output power of the energy storage battery pack is equal to zero;

[0038] The values ​​of the discharge critical power and the charge critical power are both greater than zero, and the discharge critical power is less than the charge critical power.

[0039] Furthermore, the working process of the power supply compensation module also includes:

[0040] Obtain the photovoltaic output power GC of the photovoltaic power generation equipment in the DC microgrid, the load power FH of the DC microgrid, and the battery output power DC of the energy storage battery group, and construct the relationship between the diesel generation start-up condition and the diesel generation stop condition. The relationship is as follows:

[0041] The relationship between diesel engine start-up conditions is: SOC<CL, and GC-FH<25kW;

[0042] The relationship between diesel generation conditions: SOC ≥ FL, and GC-FH > 50kW;

[0043] Substitute the power transmission data of the DC microgrid into the relationship between the diesel generation start condition and the diesel generation stop condition respectively;

[0044] If the DC microgrid meets the relational expression for diesel generator start-up conditions and the diesel generator is in the off state, the diesel generator is enabled;

[0045] If the DC microgrid meets the diesel generator shutdown condition and the diesel generator is in the on state, the diesel generator is shut down;

[0046] If the DC microgrid does not meet the relationship between the diesel generation start-up condition and the diesel generation stop-down condition, the power gap value QK of the DC microgrid is calculated according to the formula. The specific formula is as follows:

[0047] QK=GC+CC+DC-FH;

[0048] Wherein, CC is the output power of the diesel generator set. When the diesel generator set is in the on state, the output power of the diesel generator set is considered to be a constant value. When the diesel generator set is in the off state, the output power of the diesel generator set is zero. Similarly, when the energy storage battery set is in the charging mode or the free mode, the battery output power of the energy storage battery set is greater than zero. When the energy storage battery set is in the charging mode, the battery output power of the energy storage battery set is zero.

[0049] When the power gap value of the DC microgrid is less than or equal to zero, no additional operation is performed.

[0050] Furthermore, the working process of the power supply compensation module also includes:

[0051] When the power gap value of the DC microgrid is greater than zero, the battery output power of the energy storage battery group marked as the backup battery group is obtained, and the battery output power is traversed and compared with the power gap value of the DC microgrid;

[0052] If the output power of any battery in the backup battery group is greater than or equal to the power gap value, the corresponding energy storage battery group will be connected in parallel to the DC microgrid;

[0053] If the battery output power of the energy storage battery groups in the backup battery group is less than the power gap value, the battery output power of the energy storage battery group marked as the main battery group is obtained and compared with the power gap value of the DC microgrid;

[0054] If the output power of any battery in the main battery pack is greater than or equal to the power gap value, the corresponding energy storage battery pack will be connected in parallel to the DC microgrid. If the battery output power of all energy storage battery packs in the main battery pack is less than the power gap value, the backup diesel generator equipment will be enabled to connect to the DC microgrid.

[0055] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0056] The present invention first monitors the energy storage status of the energy storage battery group in real time through the energy storage monitoring module, obtains the cell status data of the energy storage battery group, and comprehensively analyzes the battery status of the energy storage battery group in combination with the cell status data. The grouping results of the main battery group, the backup battery group or the abnormal cell group are obtained through the analysis and sent to the energy storage control terminal. The working status of the energy storage battery group is immediately regulated by the energy storage control terminal. After the regulation is completed, the microgrid monitoring module is used to monitor the power transmission data of the DC microgrid in real time. The power supply compensation module performs a comprehensive analysis of the power supply situation of the DC microgrid in combination with the power transmission data. The present invention realizes intelligent power supply regulation of the DC microgrid while ensuring control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0058] Figure 1 is a block diagram of the overall system of the present invention;

[0059] Figure 2 Schematic diagram of the connection of the DC microgrid in the present invention;

[0060] Figure 3 Flow chart of the method of the present invention. DETAILED DESCRIPTION

[0061] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0062] Example 1: Please refer to Figure 1 and Figure 2 As shown, the technical solution provided by the present invention is: a DC microgrid intelligent control system based on time nodes, including an energy storage monitoring module, an energy storage analysis module, an energy storage control terminal, a microgrid monitoring module, a power supply compensation module and a processor;

[0063] See also Figure 2 As shown, in this embodiment, the DC microgrid is connected to an energy storage battery pack, a diesel generator, a photovoltaic power generation equipment, and a conversion switch. The charging voltage of the energy storage battery matches the power generation voltage of the diesel generator. Similarly, the charging voltage of the energy storage battery matches the power generation voltage of the photovoltaic power generation equipment. The conversion switch is used to control the grid connection and off-grid operation of the diesel generator and the photovoltaic power generation equipment. In actual operation, voltage matching between the power generation equipment and the energy storage battery pack is achieved through the AC / DC power distribution system and the AC / DC conversion system.

[0064] In this embodiment, the energy storage monitoring module is used to monitor the energy storage status of the energy storage battery pack in real time. The monitoring process is as follows:

[0065] The energy storage battery pack is composed of several single cells connected in series and parallel. In this embodiment, lithium iron phosphate batteries are preferably used as the energy storage battery cells. The energy storage battery pack is composed of 16 single cells, and the single cells are connected in a manner of 1 in parallel and 16 in series.

[0066] Obtaining cell status data of the energy storage battery pack through a power meter, a voltmeter, and a thermometer. The cell status data includes the cell voltage, actual cell capacity, and cell temperature of each single cell in the energy storage battery pack. In actual operation, the voltmeter is connected to both ends of the electrodes of the single cell, and the voltage reading is read as the cell voltage of the single cell. The temperature probe of the thermometer is placed in the temperature measuring hole of the single cell, and the thermometer reading is read as the cell temperature of the single cell. The electric energy stored in the single cell is measured by the power meter, and the measured value is recorded as the actual cell capacity of the single cell.

[0067] The energy storage monitoring module sends the cell status data of the energy storage battery pack to the processor, and the processor sends the cell status data of the energy storage battery pack to the energy storage analysis module.

[0068] Specifically, the energy storage analysis module is used to perform a comprehensive analysis of the battery status of the energy storage battery pack. The analysis process is as follows:

[0069] Obtain the cell voltage of each single cell in the energy storage battery pack, and compare the cell voltage of each single cell with the critical voltage range of the corresponding specification one by one;

[0070] If the cell voltage of any single cell does not fall within the critical voltage range of the corresponding specification, the corresponding single cell will be marked as an abnormal cell, and the energy storage battery group to which the single cell belongs will be marked as a cell abnormal group;

[0071] If the cell voltages of the individual cells all fall within the critical voltage range of the corresponding specifications, then the cell temperatures of the individual cells are obtained and compared with the critical temperature range of the corresponding specifications;

[0072] If the cell temperature of any single cell does not fall within the critical temperature range of the corresponding specification, the corresponding single cell will be marked as an abnormal cell, and the energy storage battery group to which the single cell belongs will be marked as a cell abnormal group;

[0073] If the cell temperatures of all single cells fall within the critical temperature range of the corresponding specifications, the corresponding energy storage battery pack will be marked as a battery pack to be sorted;

[0074] It should be noted that the value ranges of the critical voltage interval and the critical temperature interval are both referenced to the product specifications of the lithium iron phosphate battery. Specifically, the value range of the critical voltage interval is [2.5V, 3.65V], and the value range of the critical temperature interval is [-40°C, 80°C];

[0075] Obtain the cell voltage DYir, cell actual power DLir, and cell temperature DTir of each single cell in the energy storage battery pack marked as the battery pack to be sorted, where i is the sequence number of the energy storage battery pack, the upper limit of i is n, and the value of n is equal to the number of battery packs to be sorted, and r is the sequence number of the single cell, the upper limit of r is R, and the value of R is equal to the number of single cells in the energy storage battery pack;

[0076] The energy storage priority value YXi of each energy storage battery group in the battery group to be sorted is calculated according to the formula. The specific formula is as follows:

[0077]

[0078] Wherein, e is a natural constant, BY is the nominal voltage of the single cell, BT is the optimum operating temperature of the single cell, BL is the nominal capacity of the single cell, a1, a2, and a3 are weight coefficients with fixed values, the values ​​of a1, a2, and a3 are all greater than zero and a1+a2+a3=1, a1 is the voltage deviation weight, a2 is the temperature deviation weight, and a3 is the remaining energy storage capacity weight;

[0079] It can be understood that the energy storage priority value is used to reflect the matching degree between the energy storage battery pack and the photovoltaic power generation equipment. The smaller the difference between the cell voltage and the nominal voltage in the energy storage battery pack, the smaller the difference between the cell temperature and the optimum operating temperature, and the larger the difference between the nominal capacity and the actual power of the cell, the more preferentially the corresponding energy storage battery pack matches the energy storage work of the photovoltaic power generation equipment.

[0080] Comparing the energy storage priority value of each energy storage battery group in the battery group to be sorted with the energy storage priority interval;

[0081] If the energy storage priority value of the energy storage battery group belongs to the first energy storage priority interval, the corresponding energy storage battery group is classified as a backup battery group;

[0082] If the energy storage priority value of the energy storage battery group belongs to the second energy storage priority interval, the corresponding energy storage battery group is classified as a main battery group;

[0083] The values ​​of the first energy storage priority interval and the second energy storage priority interval are both greater than zero, and the values ​​of the first energy storage priority interval are both smaller than the values ​​of the second energy storage priority interval.

[0084] The energy storage analysis module sends the grouping results of the main battery group, backup battery group or abnormal cell group to the processor, and the processor sends the grouping results of the main battery group, backup battery group or abnormal cell group to the energy storage control terminal; the energy storage control terminal is used to immediately adjust the working status of the energy storage battery group. The terminal's working content is as follows:

[0085] When there is surplus photovoltaic power generation, power is first transmitted to the energy storage battery group marked as the main battery group. When all the energy storage battery groups in the main battery group are fully charged, power is switched to the backup battery group to continue transmitting power.

[0086] When the energy storage battery pack is marked as an abnormal cell group, the main battery pack or the backup battery pack is preferably replaced and staff are dispatched for inspection and maintenance.

[0087] As a further solution of the present invention, the microgrid monitoring module is used to monitor the power transmission data of the DC microgrid in real time. The monitoring process is as follows:

[0088] The power transmission data includes the photovoltaic output power of the photovoltaic power generation equipment in the DC microgrid and the load power of the DC microgrid, as well as the battery output power and battery remaining capacity of the energy storage battery pack. Among them, the photovoltaic output power is the total power output of the photovoltaic power generation equipment to the DC microgrid and the energy storage battery pack. The load power is the sum of the active power of all connected electrical appliances in the DC microgrid. The battery output power is the power output power of the energy storage battery pack currently connected to the DC microgrid. The battery remaining capacity is used to reflect the power of the energy storage battery pack. The value range of the battery remaining capacity is [0, 100%].

[0089] The microgrid monitoring module sends the power transmission data of the DC microgrid to the processor, and the processor sends the power transmission data of the DC microgrid to the power supply compensation module.

[0090] In this embodiment, the power supply compensation module is used to perform a comprehensive analysis of the power supply status of the DC microgrid. The analysis process is as follows:

[0091] Obtain the remaining capacity (SOC) of the energy storage battery pack in the DC microgrid, and compare the remaining capacity of the energy storage battery pack with the critical charge capacity (CL) and the critical discharge capacity (FL).

[0092] If the remaining capacity of the energy storage battery pack is greater than or equal to the critical charge capacity, the energy storage battery pack switches to the discharge preparation mode, that is, the battery output power of the energy storage battery pack is greater than zero;

[0093] If the remaining capacity of the energy storage battery pack is less than the critical charge capacity and greater than or equal to the critical discharge capacity, the energy storage battery pack switches to free mode, that is, the energy storage battery pack can flexibly switch between charging and discharging;

[0094] If the remaining capacity of the energy storage battery pack is less than the critical discharge capacity, the energy storage battery pack switches to the charging preparation mode, that is, the battery output power of the energy storage battery pack is equal to zero;

[0095] Among them, the values ​​of the discharge critical power and the charge critical power are both greater than zero, and the discharge critical power is less than the charge critical power;

[0096] Obtain the photovoltaic output power GC of the photovoltaic power generation equipment in the DC microgrid, the load power FH of the DC microgrid, and the battery output power DC of the energy storage battery group, and construct the relationship between the diesel generation start-up condition and the diesel generation stop condition. The relationship is as follows:

[0097] The relationship between diesel engine start-up conditions is: SOC<CL, and GC-FH<25kW;

[0098] The relationship between diesel generation conditions: SOC ≥ FL, and GC-FH > 50kW;

[0099] Substitute the power transmission data of the DC microgrid into the relationship between the diesel generation start condition and the diesel generation stop condition respectively;

[0100] If the DC microgrid meets the relational expression for diesel generator start-up conditions and the diesel generator is in the off state, the diesel generator is enabled;

[0101] If the DC microgrid meets the diesel generator shutdown condition and the diesel generator is in the on state, the diesel generator is shut down;

[0102] If the DC microgrid does not meet the relationship between the diesel generation start-up condition and the diesel generation stop-down condition, the power gap value QK of the DC microgrid is calculated according to the formula. The specific formula is as follows:

[0103] QK=GC+CC+DC-FH;

[0104] Wherein, CC is the output power of the diesel generator set. When the diesel generator set is in the on state, the output power of the diesel generator set is considered to be a constant value. When the diesel generator set is in the off state, the output power of the diesel generator set is zero. Similarly, when the energy storage battery set is in the charging mode or the free mode, the battery output power of the energy storage battery set is greater than zero. When the energy storage battery set is in the charging mode, the battery output power of the energy storage battery set is zero.

[0105] When the power gap value of the DC microgrid is less than or equal to zero, no additional operation is performed;

[0106] When the power gap value of the DC microgrid is greater than zero, the battery output power of the energy storage battery group marked as the backup battery group is obtained, and the battery output power is traversed and compared with the power gap value of the DC microgrid;

[0107] If the output power of any battery in the backup battery group is greater than or equal to the power gap value, the corresponding energy storage battery group will be connected in parallel to the DC microgrid;

[0108] If the battery output power of any energy storage battery group in the backup battery group is less than the power gap value, the battery output power of the energy storage battery group marked as the main battery group is obtained and compared with the power gap value of the DC microgrid;

[0109] If the output power of any battery in the main battery group is greater than or equal to the power gap value, the corresponding energy storage battery group will be connected in parallel to the DC microgrid;

[0110] If the battery output power of all energy storage battery packs in the main battery pack is less than the power gap value, the backup diesel generator equipment is enabled to connect to the DC microgrid. Specifically, the diesel generator equipment is controlled to connect to and exit the DC microgrid through the conversion switch.

[0111] In this application, if a corresponding calculation formula appears, the above calculation formula is dimensionless and its numerical calculation is performed. The weight coefficient, proportional coefficient and other coefficients in the formula are set to a result value obtained by quantifying each parameter. Regarding the size of the weight coefficient and the proportional coefficient, as long as it does not affect the proportional relationship between the parameter and the result value, it is acceptable.

[0112] Example 2: Figure 3 As shown, based on another concept of the same invention, a DC microgrid intelligent control method based on time nodes is proposed, comprising the following steps:

[0113] Step S100, monitoring the energy storage state of the energy storage battery pack in real time, and obtaining the cell state data of the energy storage battery pack;

[0114] Step S200, performing a comprehensive analysis on the battery status of the energy storage battery pack based on the battery cell status data, obtaining grouping results of the main battery pack, the backup battery pack, or the abnormal battery cell group, and instantly adjusting the working status of the energy storage battery pack based on the grouping results;

[0115] Step S300: After the control is completed, the power transmission data of the DC microgrid is monitored in real time;

[0116] Step S400 , comprehensively analyzing the power supply situation of the DC microgrid in combination with the power transmission data.

[0117] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to specific embodiments. Obviously, many modifications and variations are possible based on the contents of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A DC microgrid intelligent control system based on time nodes, characterized in that: It includes an energy storage monitoring module, an energy storage analysis module, an energy storage control terminal, a microgrid monitoring module, a power supply compensation module and a processor. The energy storage monitoring module is used to monitor the energy storage status of the energy storage battery pack in real time, obtain the cell status data of the energy storage battery pack through monitoring and send it to the processor. The processor sends the cell status data of the energy storage battery pack to the energy storage analysis module. The cell status data includes the cell voltage, actual cell power and cell temperature of each single cell in the energy storage battery pack. The energy storage analysis module is used to perform a comprehensive analysis on the battery status of the energy storage battery pack, and the analysis obtains the grouping results of the main battery pack, the backup battery pack or the abnormal battery cell group and sends them to the processor. The processor sends the grouping results of the main battery pack, the backup battery pack or the abnormal battery cell group to the energy storage control terminal; the energy storage control terminal is used to immediately adjust the working status of the energy storage battery pack; The analysis process of the energy storage analysis module is as follows: Obtain the cell voltage of each single cell in the energy storage battery pack, and compare the cell voltage of each single cell with the critical voltage range of the corresponding specification one by one; If the cell voltage of any single cell does not fall within the critical voltage range of the corresponding specification, the corresponding single cell will be marked as an abnormal cell, and the energy storage battery group to which the single cell belongs will be marked as a cell abnormal group; If the cell voltages of the individual cells all fall within the critical voltage range of the corresponding specifications, then the cell temperatures of the individual cells are obtained and compared with the critical temperature range of the corresponding specifications; If the cell temperature of any single cell does not fall within the critical temperature range of the corresponding specification, the corresponding single cell will be marked as an abnormal cell, and the energy storage battery group to which the single cell belongs will be marked as a cell abnormal group; If the cell temperatures of all single cells fall within the critical temperature range of the corresponding specifications, the corresponding energy storage battery pack will be marked as a battery pack to be sorted; After the control is completed, the microgrid monitoring module is used to monitor the power transmission data of the DC microgrid in real time and send the power transmission data of the DC microgrid to the processor. The processor sends the power transmission data of the DC microgrid to the power supply compensation module; the power supply compensation module is used to perform a comprehensive analysis of the power supply situation of the DC microgrid.

2. The DC microgrid intelligent control system based on time nodes according to claim 1 is characterized in that: The power transmission data includes the photovoltaic output power of the photovoltaic power generation equipment in the DC microgrid and the load power of the DC microgrid, as well as the battery output power and remaining battery capacity of the energy storage battery pack.

3. The DC microgrid intelligent control system based on time nodes according to claim 2 is characterized in that: The working process of the power supply compensation module is as follows: Obtain the remaining capacity (SOC) of the energy storage battery pack in the DC microgrid, and compare the remaining capacity of the energy storage battery pack with the critical charge capacity (CL) and the critical discharge capacity (FL). If the remaining capacity of the energy storage battery pack is greater than or equal to the critical charge capacity, the energy storage battery pack switches to the discharge preparation mode, that is, the battery output power of the energy storage battery pack is greater than zero; If the remaining capacity of the energy storage battery pack is less than the critical charge capacity and greater than or equal to the critical discharge capacity, the energy storage battery pack switches to free mode, that is, the energy storage battery pack can flexibly switch between charging and discharging; If the remaining capacity of the energy storage battery pack is less than the critical discharge capacity, the energy storage battery pack switches to the charging preparation mode, that is, the battery output power of the energy storage battery pack is equal to zero; The values ​​of the discharge critical power and the charge critical power are both greater than zero, and the discharge critical power is less than the charge critical power.

4. The DC microgrid intelligent control system based on time nodes according to claim 3 is characterized in that: The working process of the power supply compensation module also includes: Obtain the photovoltaic output power GC of the photovoltaic power generation equipment in the DC microgrid, the load power FH of the DC microgrid, and the battery output power DC of the energy storage battery group, and construct the relationship between the diesel generation start-up condition and the diesel generation stop condition. The relationship is as follows: The relationship between diesel engine start-up conditions is: SOC<CL, and GC-FH<25kW; The relationship between diesel generation conditions: SOC ≥ FL, and GC-FH > 50kW; Substitute the power transmission data of the DC microgrid into the relationship between the diesel generation start condition and the diesel generation stop condition respectively; If the DC microgrid meets the relationship of diesel generator start-up conditions and the diesel generator is in the off state, the diesel generator is enabled; If the DC microgrid meets the diesel generator shutdown condition and the diesel generator is in the on state, the diesel generator is shut down; If the DC microgrid does not meet the relationship between the diesel generation start-up condition and the diesel generation stop-down condition, the power gap value QK of the DC microgrid is calculated according to the formula. The specific formula is as follows: QK=GC+CC+DC-FH; Wherein, CC is the output power of the diesel generator set. When the diesel generator set is in the on state, the output power of the diesel generator set is considered to be a constant value. When the diesel generator set is in the off state, the output power of the diesel generator set is zero. Similarly, when the energy storage battery set is in the charging mode or the free mode, the battery output power of the energy storage battery set is greater than zero. When the energy storage battery set is in the charging mode, the battery output power of the energy storage battery set is zero. When the power gap value of the DC microgrid is less than or equal to zero, no additional operation is performed.

5. The DC microgrid intelligent control system based on time nodes according to claim 4 is characterized in that: The working process of the power supply compensation module also includes: When the power gap value of the DC microgrid is greater than zero, the battery output power of the energy storage battery group marked as the backup battery group is obtained, and the battery output power is traversed and compared with the power gap value of the DC microgrid; If the output power of any battery in the backup battery group is greater than or equal to the power gap value, the corresponding energy storage battery group will be connected in parallel to the DC microgrid; If the battery output power of the energy storage battery groups in the backup battery group is less than the power gap value, the battery output power of the energy storage battery group marked as the main battery group is obtained and compared with the power gap value of the DC microgrid; If the output power of any battery in the main battery pack is greater than or equal to the power gap value, the corresponding energy storage battery pack will be connected in parallel to the DC microgrid. If the battery output power of all energy storage battery packs in the main battery pack is less than the power gap value, the backup diesel generator equipment will be enabled to connect to the DC microgrid.

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