Electric energy management system and management method

Abstract

The present invention discloses an electric energy management system for use in a power supply system, wherein the high-voltage busbar of the power supply system is connected to the low-voltage busbar via a transformer. The system comprises an electric energy management module, an energy storage module, a high-voltage monitoring module, and a low-voltage monitoring module. The energy storage module implements a peak-shaving and valley-filling strategy for the entire plant. The energy storage module can simultaneously power both high-voltage and low-voltage loads within the plant, rather than solely serving the low-voltage side. This prevents transformer overloads within the plant and prevents the energy storage module from backfeeding power to the grid when a high-power load suddenly starts or shuts down.

Description

Technical Field

[0001] The present invention relates to the field of electric energy management, and in particular to an electric energy management system and a management method. Background Art

[0002] With the development of society, the difference between the peak and valley of electricity demand during the day and at night is increasing. Currently, the difference between the peak and valley of average electricity demand during the day and at night in most cities in China is large. In order to achieve the goal of energy conservation and emission reduction, it is necessary to implement peak shaving and valley filling through energy management systems.

[0003] At present, the power management system only implements a peak-shaving and valley-filling strategy for low-voltage side loads, and energy storage resources cannot be effectively and fully utilized. In addition, the low-voltage load capacity of general factories is limited, and the installed capacity of energy storage modules is restricted, which will also correspondingly affect profits and increase initial investment costs. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes an electric energy management system that can simultaneously perform peak shaving and valley filling processing on both the high-voltage side and the low-voltage side to improve the utilization rate of electric energy.

[0005] In a first aspect, an embodiment of the present invention provides an electric energy management system, which is applied to a power supply system, wherein a high-voltage side bus of the power supply system is connected to a low-voltage side bus via a transformer, comprising:

[0006] an electric energy management module, configured to generate a control instruction based on an operating state and power parameters of a load in the power supply system to perform electric energy management, wherein the power parameters include a first power parameter and a second power parameter;

[0007] an energy storage module, the energy storage module being connected to the low-voltage side busbar and being used for storing electric energy;

[0008] a high-voltage side monitoring module, the high-voltage side monitoring module being connected to the power management module and configured to collect the first power parameter of the load connected to the high-voltage side bus and send the first power parameter to the power management module;

[0009] A low-voltage side monitoring module is connected to the power management module and is used to collect the second power parameter of the load connected to the low-voltage side bus and send the second power parameter to the power management module.

[0010] The power management system of the embodiment of the present invention has at least the following beneficial effects: the energy storage module will implement a peak-shaving and valley-filling strategy for the entire plant area. The energy storage module can simultaneously supply power to both high-voltage and low-voltage loads within the plant area, rather than just serving the low-voltage side. When a high-power load within the plant area suddenly starts or shuts down, it avoids overloading of the plant transformer and the occurrence of power backflow from the energy storage module to the power grid.

[0011] According to some other embodiments of the electric energy management system of the present invention, the energy storage module is charged or discharged in response to the control instruction.

[0012] According to some other embodiments of the power management system of the present invention, the high-voltage side monitoring module includes at least a first electricity meter, which is used to collect the first power parameter of the load connected to the high-voltage side bus and send the first power parameter to the power management module.

[0013] According to some other embodiments of the power management system of the present invention, the low-voltage side monitoring module includes at least a second electricity meter, which is used to collect the second power parameter of the load connected to the low-voltage side bus and send the first power parameter to the power management module.

[0014] According to some other embodiments of the electric energy management system of the present invention, the high-voltage side monitoring module is configured with a corresponding number of electric meters according to the number of loads connected to the high-voltage side bus.

[0015] According to some other embodiments of the electric energy management system of the present invention, the low-voltage side monitoring module is configured with a corresponding number of electric meters according to the number of loads connected to the low-voltage side bus.

[0016] Configure different numbers of electricity meters according to needs to achieve accurate collection of load parameters.

[0017] According to some other embodiments of the present invention, the power management system further includes a third electricity meter, which is used to collect power parameters of the energy storage module.

[0018] According to some other embodiments of the electric energy management system of the present invention, if the collected power of any electric meter in the high-voltage side monitoring module is less than a first preset value, the discharge power of the energy storage module is reduced.

[0019] By setting the first and second switches, the power parameters of each load can be flexibly collected.

[0020] According to some other embodiments of the power management system of the present invention, if the collected power of any electric meter in the low-voltage side monitoring module is greater than a second preset value, the charging power of the energy storage module is reduced.

[0021] The first preset value and the second preset value ensure that when a large motor is suddenly started or stopped, the transformer of the energy storage module is not overloaded during the charging period and electric energy does not flow into the grid during the discharging period, thereby avoiding the occurrence of reverse power supply in the system.

[0022] In a second aspect, an embodiment of the present invention provides an electric energy management method, which is applied to a power supply system, wherein a high-voltage side busbar of the power supply system is connected to a low-voltage side busbar via a transformer, and is characterized in that:

[0023] Acquire the working status and power parameters of the load in the power supply system, where the power parameters include a first power parameter and a second power parameter;

[0024] generating a control instruction according to the electricity price status, the working status and the power parameters;

[0025] The energy storage system performs power management according to the control instructions.

[0026] The electric energy management method of the embodiment of the present invention has at least the following beneficial effects: by monitoring the working status and power parameters of the high-voltage side and low-voltage side loads, the energy storage module will implement a peak-shaving and valley-filling strategy for the entire plant area. The energy storage module can simultaneously supply power to the high-voltage side loads and the low-voltage side loads in the plant area, rather than just serving the low-voltage side. When a high-power load in the plant area suddenly starts or stops, it avoids overloading of the transformer in the plant area and the occurrence of power backflow from the energy storage module to the power grid.

[0027] According to some other embodiments of the electric energy management method of the present invention, generating a control instruction according to the working state and power parameters includes: generating a first control instruction in combination with an electricity price state and a load working state.

[0028] According to some other embodiments of the present invention, the power management method generates a control instruction according to the working state and power parameters, further comprising:

[0029] Setting a first preset value and a second preset value;

[0030] If the first power parameter is less than a first preset value, generating a second control instruction;

[0031] If the second power parameter is greater than a second preset value, a third control instruction is generated.

[0032] According to some other embodiments of the present invention, the power management method, performing power management according to the control instruction, includes:

[0033] In response to the first control instruction, determining a charge and discharge state of the energy storage module;

[0034] In response to the second control instruction, reducing the discharge power of the energy storage module;

[0035] In response to the third control instruction, the charging power of the energy storage module is reduced.

[0036] According to the power management method of some other embodiments of the present invention, the working state includes any one of the following: starting, stopping or power sudden change. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a system framework diagram of the power management system in an embodiment of the present invention;

[0038] Figure 2 is a topological diagram of an electric energy management system according to an embodiment of the present invention;

[0039] Figure 3 is a topological diagram of an electric energy management system according to another embodiment of the present invention;

[0040] Figure 4 is a topological diagram of an electric energy management system according to another embodiment of the present invention;

[0041] Figure 5 This is a flowchart of a specific embodiment of the power management method in an embodiment of the present invention;

[0042] Figure 6 yes Figure 5 A schematic flow chart of a specific embodiment of S200;

[0043] Figure 7 yes Figure 5 Another specific embodiment of S200 is shown in the flowchart

[0044] Figure 8 yes Figure 5 A flowchart of a specific embodiment of S300 is shown in FIG.

[0045] Reference numerals

[0046] 100, high-voltage side bus; 200, low-voltage side bus; 300, transformer; 400, high-voltage side monitoring module; 410, first electric meter; 420, fourth electric meter; 500, low-voltage side monitoring module; 510, second electric meter; 520, fifth electric meter; 600, high-voltage side load; 610, first load; 620, second load; 700, low-voltage side load; 710, third load; 720, fourth load; 110, first switch; 210, second switch; 800, third electric meter. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0048] In the description of the present invention, if any directional description is involved, such as "upper," "lower," "front," "back," "left," "right," etc., indicating directions or positional relationships, these are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed or operate in a specific orientation. Therefore, they should not be understood as limiting the present invention. If a feature is referred to as being "disposed," "fixed," "connected," or "mounted" on another feature, it may be directly disposed, fixed, or connected to the other feature, or indirectly disposed, fixed, connected, or mounted on the other feature.

[0049] In the description of the embodiments of the present invention, if the word "several" is mentioned, it means more than one; if the word "plurality" is mentioned, it means more than two; if the word "greater than," "less than," or "exceeds," it should be understood as excluding the number itself; if the word "above," "below," or "within" is mentioned, it should be understood as including the number itself. If the word "first" or "second" is mentioned, it should be understood as distinguishing technical features and should not be understood as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0050] As society develops, the difference between daytime and nighttime peaks and valleys in electricity demand continues to widen. Currently, the average daily peak-to-valley difference in electricity demand in most Chinese cities exceeds 60%. Balancing this significant difference in daytime and nighttime demand is a challenge that most power systems must address in order to achieve energy conservation and emissions reduction.

[0051] At present, energy storage modules are connected to the low-voltage side, and only the peak-shaving and valley-filling strategy is implemented for the low-voltage side load. Energy storage resources cannot be effectively and fully utilized. In addition, the low-voltage load capacity of general factories is limited, and the installed capacity of energy storage modules is limited, which will also affect the benefits and increase the initial investment costs.

[0052] In the case of a large-load motor, when the energy storage module is running, the sudden start-up or shutdown of the high-power load will greatly cause the transformer to overload or the system to reverse power, resulting in safety hazards to the factory due to the addition of the energy storage module.

[0053] Based on this, the embodiment of the present invention provides an electric energy management system, which is mainly used for the power supply system of a factory with a large-power motor (load) to implement the peak-shaving and valley-filling strategy application. Figure 1 The high-voltage busbar 100 of the power supply system is connected to the low-voltage busbar 200 via a transformer 300. The high-voltage busbar 100 is typically connected to two 10kV or 6kV power sources, preferably 10kV power sources. The high-voltage busbar 100 is connected to the low-voltage busbar 200 via two transformers 300. The transformers 300 step down the 10kV voltage to 0.4kV. In this embodiment, the first load 610, the second load 620, the third load 710, and the fourth load 720 are high-power loads, more specifically, high-power motors.

[0054] Reference Figure 1 , shows a block diagram of the power management system structure in an embodiment of the present invention. It specifically includes: power management module, energy storage module, high-voltage side monitoring module 400, low-voltage side monitoring module 500, Figure 1 EMS and ESS represent the energy management module and energy storage module respectively.

[0055] In one embodiment, the power management module is respectively connected to the energy storage module, the high-voltage side monitoring module 400, the low-voltage side monitoring module 500 and each load, and is used to generate control instructions and perform power management functions based on the working status signals of the loads in the power supply system (for example, start-stop signals and power mutation signals) and the power parameters of the loads detected by the high-voltage side monitoring module 400 and the low-voltage side monitoring module 500; wherein the power parameters include a first power parameter and a second power parameter, specifically, the first power parameter is the power parameter of the high-voltage side load 600, and the second power parameter is the power parameter of the low-voltage side load 700.

[0056] The energy storage module is connected to the low-voltage bus 200 and is used to store electrical energy, supplying power to loads within the plant when in a discharged state. The high-voltage monitoring module 400 is connected to the power management module and is used to collect a first power parameter of the load connected to the high-voltage bus 100. The low-voltage monitoring module 500 is connected to the power management module and is used to collect a second power parameter of the load connected to the low-voltage bus 200.

[0057] In some embodiments, a high-voltage side monitoring module 400 and a low-voltage side monitoring module 500 are respectively provided on the high-voltage side and the low-voltage side, and the power parameters and start / stop signals of the high-voltage side load 600 (for example, the first load 610 and the second load 620) and the low-voltage side load 700 (for example, the third load 710 and the fourth load 720) are respectively detected, and a peak shaving and valley filling strategy is implemented for the high-voltage side load 600 and the low-voltage side load 700 to improve the utilization rate of electric energy.

[0058] In this embodiment, different power parameters can be collected according to the opening and closing of the first switch 110 and the second switch 210. For example, when the first switch 110 is disconnected, the first electric meter 410 only collects the power parameters of the first load 610. When the first switch 110 is closed, the first electric meter 410 collects the power parameters of the first load 610 and the second load 620 at the same time.

[0059] In this embodiment, the power management module can detect the motor start or stop signal, combine the local electricity price status, determine the charge and discharge status of the energy storage system, and perform the following power management (peak shaving and valley filling) function.

[0060] Refer to the table below. Voltage is categorized into three power price states: valley, flat, and peak, based on power usage periods. When the power price is at its peak, the plant's loads are operating. During this time, the power management module fully discharges the energy storage module, allowing the energy storage system to supply power to the plant's loads. When the power price is flat, the energy storage system is put into standby mode. When the power price is at its valley, the plant's loads are shut down, and the power management module charges the energy storage module. By discharging the energy storage module during peak usage and charging it during off-peak usage, the power price difference is effectively utilized, lowering the overall electricity price, improving energy utilization, and reducing the plant's electricity costs.

[0061] The load in this embodiment is a high-power motor, usually with a power greater than 100kW. When the high-power motor is started, the energy storage system's electrical energy can be more fully utilized, the number of daily charge and discharge times and the amount of electricity can be increased, and at the same time, the benefits will also increase.

[0062]

[0063] In order to prevent the transformer 300 from being overloaded during the above-mentioned charging period and to prevent electric energy from flowing into the power grid during the discharging period, in some embodiments, the high-voltage side monitoring module 400 and the low-voltage side monitoring module 500 are configured as a corresponding number of electric meters according to the number of loads connected to the high-voltage side bus 100 and the low-voltage side bus 200, respectively.

[0064] Reference Figure 2In some embodiments, the high-voltage side monitoring module 400 includes a first electric meter 410, the low-voltage side monitoring module 500 includes a second electric meter 510, and the high-voltage side bus 100 and the low-voltage side bus 200 are respectively provided with a first switch 110 and a second switch 210. When the energy storage module is charging, the first preset value and the second preset value are first set to ensure that any second power parameter collected by the second electric meter 510 does not exceed the second preset value. During discharge, any first power parameter collected by the first electric meter 410 is not less than the first preset value. At the same time, the power management module collects the start and stop signals of the high-voltage side load 600 and the low-voltage side load 700 to ensure that under the condition of sudden start or shutdown of the load, the energy storage module does not overload the transformer 300 during the charging period and the electric energy does not flow into the power grid during the discharge period, thereby avoiding the occurrence of system backflow.

[0065] In one specific embodiment, during charging, to ensure that transformer 300 is not overloaded, the second set value is set to 640kW. When any second power parameter collected by second electricity meter 510 or fifth electricity meter 520 exceeds 640kW, a third control instruction is generated to control the charging system to reduce the charging power. During discharging, to prevent electrical energy from flowing into the grid, the first set value is 250kW (of which 50kW is reserved power). When any first power parameter collected by first electricity meter 410 or fourth electricity meter 420 is less than 200kW, a second control instruction is generated to control the energy storage system to reduce the discharge power.

[0066] refer to Figure 3 In one embodiment, the high-voltage side monitoring module 400 includes a first electric meter 410 and a fourth electric meter 420, and the low-voltage side monitoring module 500 includes a second electric meter 510 and a fifth electric meter 520. At this time, the first switch 110 on the high-voltage side bus 100 is located between the first electric meter 410 and the fourth electric meter 420, and the second switch 210 on the low-voltage side bus 200 is located between the second electric meter 510 and the fifth electric meter 520.

[0067] When the energy storage module is charging, the first preset value and the second preset value are first set to ensure that the power collected by the second meter 510 and the fifth meter 520 does not exceed the second preset value. When discharging, the power collected by the first meter 410 and the fourth meter 420 is not less than the first preset value. At the same time, the power management module collects the start and stop signals of the high-power motor to ensure that when the large motor suddenly starts or stops, the transformer 300 of the energy storage module is not overloaded during the charging period and the electric energy does not flow into the power grid during the discharging period, thereby avoiding the occurrence of system power backflow.

[0068] In this embodiment, any collected power refers to the power of the load under the corresponding meter. For example, when the first switch 110 is disconnected, the first meter 410 can measure the power of the first load 610. When the first switch 110 is closed, the meter can simultaneously measure the power of the first load 610 and the second load 620. By controlling the opening and closing of the first switch 110 and the second switch 210, the power parameters of different loads can be flexibly obtained.

[0069] In other embodiments, according to the number of loads on the high-voltage side bus 100 and the low-voltage side bus 200 , a plurality of electric meters may be provided for detecting power parameters of the loads respectively.

[0070] Reference Figure 4 In some embodiments, the power management system further includes a third electric meter 800. During the operation of the plant energy storage module, if a large motor suddenly starts up within the plant, this can overload the transformer 300 and cause a power outage. Alternatively, if a large motor suddenly shuts down during the operation of the plant energy storage module, the energy storage module's power supply may exceed the plant load, leading to reverse power flow from the energy storage module to the grid. For example, if the energy storage module is larger than the plant load, this excessive reverse power flow can cause grid oscillations. When the municipal grid is shut down for maintenance, this reverse power flow can also cause accidents such as electric shock to maintenance personnel.

[0071] It should be noted that the start and stop of high-power motors in the factory are controlled by the control center, not by the factory itself, so the start and stop of the motors cannot be controlled within the station.

[0072] Therefore, in this embodiment, the third electric meter 800 can be used to measure the charge and discharge power of the energy storage module. If the power collected by either the second electric meter 510 or the fifth electric meter 520 reaches a second preset value during charging, the energy storage module reduces the charging power to ensure that the transformer 300 is not overloaded. If the power collected by the first electric meter 410 or the fourth electric meter 420 is less than the first preset value during discharging, the energy storage module reduces the discharge power to ensure that the electric energy does not flow into the grid.

[0073] In some embodiments, due to the extremely high power of large motors, sudden startup or shutdown can cause significant fluctuations in the plant's load. Without this delay function, sudden motor startup could overload the plant's transformer 300, while sudden motor shutdown could cause the energy storage system to lose power and send it to the grid. This delay allows the power management module sufficient time to react and make appropriate adjustments. To this end, a 2-8 second delay is implemented for motor startup and shutdown, optionally 4-7 seconds, and further optionally 5 seconds.

[0074] Current energy storage modules can only provide active power P, but the total reactive power Q of the plant load remains unchanged. Conventional energy storage modules provide some active power, so the active power P provided by the grid to the plant is reduced. However, the reactive power Q provided by the grid to the plant load remains unchanged. Therefore, the proportion of reactive power Q in apparent power S on the grid side increases, lowering the power factor of the plant. Due to the requirements of the power supply bureau, a low power factor of the plant will result in fines and huge losses.

[0075] Since some plant areas do not have reactive power compensation or have insufficient compensation capacity, the power management system according to this embodiment can realize the reactive power compensation function of the plant areas.

[0076] In some embodiments, the power management module collects peak and valley power data from the third power meter 800, while the first power meter 410 and the fourth power meter 420 collect the load's active power P, reactive power Q, and power factor cos@. When the EMS detects that the power factor in the factory is lower than 0.95, it calculates the power factor according to the following formulas (1) and (2):

[0077] (1)

[0078] (2)

[0079] The power management module can always keep the power factor cos@ greater than 0.95 by increasing the active power of the load. Because the load of the factory area fluctuates, the amount of data collected by the energy storage module is large, and the response speed will be slightly delayed. In order to avoid the energy storage module responding to power factor fluctuations in real time, the power management module collects data and performs calculations at a frequency of every 20-40 minutes / time, and then issues control instructions to the energy storage module, optionally with a frequency of 25-35 minutes / time, and further optionally, a frequency of 30 minutes / time. The energy storage module responds to the control instructions of the power management module and outputs reactive power for a period of 30 minutes.

[0080] In this embodiment, the energy storage module can realize the reactive power compensation function of the plant area on the basis of peak shaving and valley filling. It can improve and maintain the power factor of the plant load to avoid the reduction of the plant power factor due to the use of new energy or other factors. At the same time, it can avoid the power supply bureau's requirements and fines on the plant area due to too low a power factor.

[0081] In a second aspect, the present invention provides an energy management method, referring to Figure 5 , the method comprising:

[0082] S100: Acquire the working status and power parameters of the load in the power supply system, where the power parameters include a first power parameter and a second power parameter;

[0083] S200: Generate control instructions based on electricity price status, load operating status and power parameters;

[0084] S300: The energy storage system performs power management according to the control instructions.

[0085] In some embodiments, in step S100, the power management module respectively obtains the working status of the high-voltage side load 600 and the low-voltage side load 700 (for example, start-stop signals and power mutation signals) and the power parameters of the loads detected by the high-voltage side monitoring module 400 and the low-voltage side monitoring module 500. Specifically, the first power parameter is the power parameter of the high-voltage side load 600, and the second power parameter is the power parameter of the low-voltage side load 700.

[0086] In some embodiments, in steps S200 and S300, the power management module generates a control instruction based on the first power parameter and the second power parameter and the working state and electricity price state of the corresponding side load, and the energy storage system performs power management according to the control instruction.

[0087] By monitoring the operating status and power parameters of the high- and low-voltage loads, the energy storage module implements a peak-shaving and valley-filling strategy for the entire plant. Rather than serving only the low-voltage side, the module can simultaneously power both the high-voltage load (600) and the low-voltage load (700). This prevents overloading of the plant's transformer (300) and backfeeding of power from the energy storage module to the grid if a high-power load suddenly starts or shuts down.

[0088] In some embodiments, reference Figure 6 , step S200 includes the following steps:

[0089] S210: Generate a first control instruction based on the electricity price status and the load working status. As before, based on the local electricity price status in different time periods and the working status of the load in the factory area, the first control instruction is generated. The first control instruction is used to determine the charge and discharge status of the energy storage module and implement the peak-shaving and valley-filling charging strategy.

[0090] In one specific embodiment, the voltage is divided into three electricity price states: valley, flat, and peak, according to the electricity usage period. When the electricity price is at its peak, the factory load is operating. At this time, the first control instruction generated by the power management module is used to control the energy storage module to fully discharge, using the energy storage system to supply power to the load within the factory. When the electricity price is flat, the first control instruction generated by the power management module is used to put the energy storage system into standby mode. When the electricity price is at its valley value, the factory load is shut down. At this time, the first control instruction generated by the power management module is used to control the charging of the energy storage module. By discharging the energy storage module during peak electricity usage and charging it during low electricity usage, the difference in electricity prices is effectively utilized, the total electricity price is reduced, the utilization rate of electricity is improved, and the electricity cost of the factory is reduced.

[0091] In some embodiments, reference Figure 7 , step S200 further includes the following steps:

[0092] S220: Setting a first preset value and a second preset value;

[0093] S230: If the first power parameter is less than the first preset value, generate a second control instruction;

[0094] S240: If the second power parameter is greater than the second preset value, generate a third control instruction.

[0095] The first preset value and the second preset value are manually set safety values. During charging, when the second power parameter exceeds the second preset value, the transformer 300 is at risk of overload, and a third control instruction is generated. During discharging, when the first power parameter is less than the first set value, the plant load is less than the discharge capacity of the energy storage system, and there is a risk of backfeeding power to the grid, and a second control instruction is generated.

[0096] In some embodiments, reference Figure 8 , execute power management according to control instructions, including:

[0097] S310: Determine a charge and discharge state of the energy storage module in response to a first control instruction;

[0098] S320: In response to the second control instruction, reduce the discharge power of the energy storage module to avoid the risk of the energy storage system feeding back power to the power grid.

[0099] S330: In response to the third control instruction, reduce the charging power of the energy storage module to avoid the risk of overload of the transformer 300.

[0100] In one specific embodiment, during charging, to ensure the transformer is not overloaded, the second preset value is set to 640kW. When any of the second power parameters measured by the second electricity meter 510 and the fifth electricity meter 520 exceeds 640kW, a third control instruction is generated to control the charging system to reduce the charging power. The second preset value is generally set to 80% of the rated capacity of the transformer, while the first preset value is based on the minimum load power supply in the factory area.

[0101] During discharge, in order to prevent electric energy from flowing into the grid, the first preset value is 250kW (of which 50kW is reserved power). When any first power parameter collected by the first electricity meter 410 and the fourth electricity meter 420 is less than 200kW, a second control instruction is generated to control the energy storage system to reduce the discharge power.

[0102] In other embodiments, in order to implement control over other aspects of the power management system, the parameters collected by each meter include but are not limited to the following parameters:

[0103] (1) Common information such as total voltage, current, average temperature, SOC, SOH, charge and discharge current and power limit of each battery group, single battery voltage, single battery temperature, balance status of each battery, fault and alarm information, historical charge and discharge power, historical charge and discharge energy, etc.

[0104] (2) Relevant parameters of the bidirectional converter system, including voltage / current / power on the DC side, three-phase active power, reactive power, three-phase voltage, three-phase current, power factor, frequency, operating status, alarm and fault information of each bidirectional converter, as well as daily input power, daily output power, cumulative input power, cumulative output power, etc.

[0105] (3) The various status quantities of the energy storage module, including the main circuit status (switch, accident trip signal, protection action signal, abnormal signal, etc.), fire alarm, temperature and other information, are displayed.

[0106] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. An electric energy management system, applied to a power supply system, wherein the high-voltage side bus of the power supply system is connected to the low-voltage side bus via a transformer, characterized in that: include: An electric energy management module, configured to generate a control instruction based on the operating status and power parameters of the load in the power supply system, wherein the power parameters include a first power parameter and a second power parameter; wherein the first power parameter is the power parameter of the high-voltage side load, and the second power parameter is the power parameter of the low-voltage side load; An energy storage module, the energy storage module is connected to the low-voltage side bus and is used to store electric energy; the electric energy management module is used to control the charging and discharging of the energy storage module and adjust the charging and discharging power of the energy storage module according to the control instructions to achieve electric energy management; a high-voltage side monitoring module, the high-voltage side monitoring module being connected to the power management module and configured to collect the first power parameter of the load connected to the high-voltage side bus and send the first power parameter to the power management module; a low-voltage side monitoring module, the low-voltage side monitoring module being connected to the power management module and configured to collect the second power parameter of the load connected to the low-voltage side bus and send the second power parameter to the power management module; The high-voltage side monitoring module is configured with a corresponding number of electric meters according to the number of loads connected to the high-voltage side bus; the low-voltage side monitoring module is configured with a corresponding number of electric meters according to the number of loads connected to the low-voltage side bus; The power management system further includes a third electric meter, which is used to collect electric energy parameters of the energy storage module; The energy storage module is charged or discharged in response to the control instruction; The power management module is also used to: divide the voltage into three electricity price states: valley, flat and peak according to the electricity consumption period. When the electricity price is at the peak, it is the time period when the factory load is working. At this time, the power management module controls the energy storage module to fully discharge. When the electricity price is at the flat value, the energy storage module is put into standby mode; when the electricity price is at the valley value, the power management module controls the energy storage module to charge.

2. The power management system according to claim 1, characterized in that: The high-voltage side monitoring module includes at least a first electricity meter, which is used to collect the first power parameter of the load connected to the high-voltage side bus and send the first power parameter to the power management module.

3. The power management system according to any one of claims 1 to 2, characterized in that: The low-voltage side monitoring module includes at least a second electric meter, which is used to collect the second power parameter of the load connected to the low-voltage side bus and send the first power parameter to the power management module.

4. An electric energy management method, applied to a power supply system, wherein a high-voltage busbar of the power supply system is connected to a low-voltage busbar via a transformer, characterized in that: The method comprises: Obtaining the operating status and power parameters of the load in the power supply system, the power parameters including a first power parameter and a second power parameter; wherein the first power parameter is the power parameter of the high-voltage side load, and the second power parameter is the power parameter of the low-voltage side load; Generate control instructions based on electricity price status, working status and power parameters; The generating of control instructions according to the electricity price status, working status and power parameters includes: generating a first control instruction based on the electricity price status and the load operating status; Setting a first preset value and a second preset value; If the first power parameter is less than a first preset value, generating a second control instruction; If the second power parameter is greater than a second preset value, generating a third control instruction; In response to the first control instruction, determining a charge and discharge state of the energy storage module; In response to the second control instruction, reducing the discharge power of the energy storage module; In response to the third control instruction, the charging power of the energy storage module is reduced.

5. The power management method according to claim 4, characterized in that: The working state includes any one of the following: starting, stopping or power sudden change.

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