An intelligent energy storage system suitable for non-return bidirectional switching power supply

Abstract

The present invention relates to the field of intelligent energy storage systems, and is used to solve the problem of increased maintenance costs caused by insufficient utilization of battery cells in energy storage systems. Specifically, the present invention relates to an intelligent energy storage system suitable for a non-reflux bidirectional switching power supply, comprising a load monitoring unit, a power switching control unit, a battery usage statistics unit, a battery status analysis unit, and a battery life monitoring unit. In the present invention, by balancing the relationship between the number of charge and discharge times and the usage time of battery cells in the energy storage system, the number of charge and discharge times and the usage time of the battery cells can reach the warranty period at the same time as much as possible, avoiding the situation where the warranty period and the number of charge and discharge times are too far from the warranty upper limit, thereby improving the economy of maintenance or replacement. By separately monitoring two groups of battery cells, the supervision of multiple groups of battery cells can be achieved at the same time, and the early warning supervision work can be completed. At the same time, when an abnormality occurs in an individual battery cell, an automatic switching operation can be performed to ensure the safety of the intelligent energy storage system.

Description

Technical Field

[0001] The present invention relates to the field of intelligent energy storage systems, and in particular to an intelligent energy storage system suitable for a non-return bidirectional switching power supply. Background Art

[0002] The energy storage dual power switch is a switch that automatically switches the energy storage device to another power source according to the load power consumption, thereby improving the utilization rate of energy storage. It is generally widely used in scenarios such as charging pile storage and peak-shaving. As we all know, most energy storage now uses lithium iron phosphate cells, which are expensive. Most of the cells on the market have a cycle life of 0.5P, 6000 times, a warranty life of 5 years, and SOH80% are calculated on a first-come-first-served basis. Taking 6000 times as an example, it takes more than 8 years to achieve 6000 cycles of two charges and two discharges a day, and due to the load usage, most of them cannot actually be fully charged and discharged;

[0003] At present, the smart energy storage system in the prior art still has some shortcomings. When the battery cells of the existing energy storage system are cycled, due to the difference between the number of charge and discharge times and the warranty period, most of the battery cells will still have a large surplus of charge and discharge times when the warranty period expires. Therefore, the maintenance and replacement of expired battery cells often leads to a significant increase in maintenance costs due to insufficient battery cell utilization.

[0004] In view of the above technical problems, this application proposes a solution. Summary of the invention

[0005] In the present invention, by balancing the relationship between the number of charge and discharge times and the usage time of the battery cells in the energy storage system, the number of charge and discharge times and the usage time of the battery cells can reach the warranty period at the same time as much as possible, avoiding the situation that the usage time reaches the warranty period but the number of charge and discharge times is still far from the warranty number, or the number of charge and discharge times reaches the warranty number but the usage time is far from the warranty period, thereby improving the economy of maintenance or replacement, and by separately monitoring the two groups of battery cells, the supervision work of multiple groups of battery cells can be realized at the same time, and the early warning supervision work can be completed. At the same time, when an abnormality occurs in an individual battery cell, an automatic switching operation can be performed to ensure the safety of the intelligent energy storage system, solve the problem of increased maintenance cost due to insufficient usage of the battery cells in the energy storage system, and propose an intelligent energy storage system suitable for a non-reflux bidirectional switching power supply.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] An intelligent energy storage system suitable for a non-return bidirectional switching power supply includes a load monitoring unit, wherein the load monitoring unit is used to monitor the load of the energy storage power supply and balance the power of the energy storage power supply with the load of the energy storage power supply;

[0008] A power switching control unit, which can control the use of the battery, switch the working state of the battery, and issue an early warning reminder for abnormal batteries;

[0009] A battery usage statistics unit, which can collect statistics on battery usage and upload the statistics via a network;

[0010] A battery status analysis unit, which can collect operating parameters of the battery, analyze the operating status of the battery according to the operating parameters, generate analysis results and send them to the power switching control unit;

[0011] The battery life monitoring unit can perform statistical analysis on the number of times the battery is charged and discharged and the usage of the battery, and determine whether the number of times the battery is charged and discharged and the usage time are balanced based on the analysis results.

[0012] As a preferred embodiment of the present invention, the load monitoring unit is preset with a power load threshold. The load monitoring unit compares the power load of the energy storage power supply with the different power load thresholds preset by the load monitoring unit. If the power load of the energy storage power supply is less than the preset power load threshold, the energy storage power supply is operated in a low-power state. If the power load of the energy storage power supply is greater than or equal to the preset power load threshold, the energy storage energy is operated in a high-power state.

[0013] As a preferred embodiment of the present invention, the battery life monitoring unit analyzes the number of times of charging and discharging and the usage of the battery as follows:

[0014] Step 1: The battery life monitoring unit records the installation time of the battery, and records the installed time of the two sets of energy storage batteries as the first battery usage time and the second battery usage time. The battery life monitoring unit obtains the warranty time of the battery, and divides the first battery usage time by the warranty time to obtain the first battery usage rate, and divides the second battery usage time by the warranty time to obtain the second battery usage rate;

[0015] Step 2: The battery life monitoring unit collects the charge and discharge behavior of the energy storage battery, analyzes the charge and discharge rate and the number of charge and discharge times, and obtains the first battery charge and discharge rate and the second battery charge and discharge rate respectively;

[0016] Step three: The battery life monitoring unit calculates the difference between the first battery usage rate and the first battery charge and discharge rate, and records it as the first battery difference rate. It calculates the difference between the second battery usage rate and the second battery charge and discharge rate, and records it as the second battery difference rate. The battery life monitoring unit compares the first battery difference rate with the second battery difference rate, and records the larger group of batteries in the comparison result as large-difference batteries. The large-difference batteries are sent to the power switching control unit. After the power switching control unit obtains the large-difference batteries, it records the large-difference batteries as energy supply batteries, and supplies power through the large-difference batteries.

[0017] As a preferred embodiment of the present invention, the method for the battery life monitoring unit to obtain the first battery charge and discharge rate and the second battery charge and discharge rate is:

[0018] The battery life monitoring unit collects the charging and discharging behaviors of the energy storage battery. At the same time, the battery life monitoring unit counts the battery charging rate and battery discharging rate in each charging and discharging process, and starts timing when the battery charging and discharging starts and ends when the battery charging and discharging is completed. The charging rate or discharge rate obtained during the charging and discharging process is arithmetic averaged, and the average value is recorded as the average charging rate or the average discharge rate. The battery life monitoring unit obtains the battery cycle characteristic value through formula analysis. When the battery is in a charging state, the average discharge rate is recorded as 0, and when the battery is in a discharging state, the average charging rate is recorded as 0. The battery life monitoring unit uses the battery cycle characteristic value as an equivalent number of charges and discharges. At the same time, the battery life monitoring unit records the battery cycle characteristic values ​​of the two groups of energy storage batteries as the first battery charge and discharge number and the second battery charge and discharge number, respectively. The battery life monitoring unit obtains the preset warranty charge and discharge number, divides the first battery charge and discharge number by the preset warranty charge and discharge number, and records it as the first battery charge and discharge rate, and divides the second battery charge and discharge number by the preset warranty charge and discharge number, and records it as the second battery charge and discharge rate.

[0019] As a preferred embodiment of the present invention, the battery state analysis unit collects the operating state of the energy storage battery, the operating state of the energy storage battery includes the operating temperature and the operating stability, the battery state analysis unit obtains a preset temperature standard range, and records the collected operating temperatures of the two groups of energy storage batteries as the first battery temperature and the second battery temperature, respectively, and compares the first battery temperature and the second battery temperature with the preset temperature standard range, respectively, if the temperature is outside the preset temperature standard range, then the value of the temperature exceeding the temperature standard range is calculated and recorded as the temperature exceeding rate, if the temperature is within the preset temperature standard range, then the temperature exceeding rate is 0, the value obtained by the first battery temperature calculation is recorded as the first temperature exceeding rate, and the value obtained by the second battery temperature calculation is recorded as the second temperature exceeding rate;

[0020] The battery state analysis unit detects the output power and input power of the energy storage battery, records the output power difference between two adjacent output power detections as the output variation value, and records the input power difference between two adjacent input power detections as the input variation value. The battery state analysis unit averages the output variation value and the input variation value of the energy storage battery to obtain an average operation fluctuation, and records the average operation fluctuations of the two groups of energy storage batteries as a first operation fluctuation and a second operation fluctuation, respectively.

[0021] The battery status analysis unit compares the first temperature exceedance rate with the second temperature exceedance rate, records the energy storage battery with a larger temperature exceedance rate as an abnormal battery, and sends the abnormal battery to the power switching control unit. The battery status analysis compares the first operation fluctuation with the second operation fluctuation, records the energy storage battery with a larger operation fluctuation as a fluctuating battery, and sends the fluctuating battery to the power switching control unit.

[0022] As a preferred embodiment of the present invention, after the power switching control unit obtains an abnormal battery or a fluctuating battery, it generates an abnormal reminder signal. If the abnormal battery and the fluctuating battery are the same battery, a battery shutdown signal is generated at the same time as the abnormal reminder signal, and the abnormal and fluctuating battery is stopped from operating and switched to another group of batteries for operation.

[0023] As a preferred embodiment of the present invention, the battery usage statistics unit can obtain the batteries that are currently in working state in real time, count the usage time of the batteries in working state, and calculate the operating time proportion of the two groups of energy storage batteries by dividing the cumulative usage time of a single group of batteries by the total usage time.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. In the present invention, by balancing the relationship between the number of charge and discharge times and the usage time of the battery cells in the energy storage system, the number of charge and discharge times and the usage time of the battery cells can reach the warranty period at the same time as much as possible, avoiding the situation where the usage time reaches the warranty period but the number of charge and discharge times is still far from the warranty number, or the number of charge and discharge times reaches the warranty number but the usage time is far from the warranty period, thereby improving the economy of maintenance or replacement.

[0026] 2. In the present invention, by separately monitoring two groups of battery cells, it is possible to simultaneously monitor multiple groups of battery cells and complete early warning monitoring work. At the same time, when abnormalities occur in individual battery cells, automatic switching operations can be performed to ensure the safety of the intelligent energy storage system.

[0027] 3. In the present invention, the energy storage control system and two control circuit breakers are used to realize the battery cell control. The energy storage control system can control the two control circuit breakers to change the switch state when receiving the switch switching signal, switch the energy storage battery used for power supply, and the two control circuit breakers cannot be closed at the same time to avoid the occurrence of power circulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0029] Figure 1 is a system block diagram of the present invention;

[0030] Figure 2 It is a system flow chart of the present invention. DETAILED DESCRIPTION

[0031] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Embodiment 1:

[0033] See also Figure 1 - Figure 2 As shown, an intelligent energy storage system suitable for a non-reflow bidirectional switching power supply includes a load monitoring unit, a power switching control unit, a battery usage statistics unit, a battery status analysis unit and a battery life supervision unit. The load monitoring unit is used to supervise the load of the energy storage power supply and monitor the power load brought by the load device. The load monitoring unit is preset with a power load threshold. The load monitoring unit compares the power load of the energy storage power supply with different power load thresholds preset by the load monitoring unit. If the power load of the energy storage power supply is less than the preset power load threshold, the energy storage power supply is operated in a low power state. If the power load of the energy storage power supply is greater than or equal to the preset power load threshold, the energy storage energy is operated in a high power state.

[0034] The energy storage power supply includes two groups of energy storage batteries, which are switched between by an energy storage switching device. The energy storage switching device consists of an energy storage control system based on an STM32 single-chip microcomputer and two control circuit breakers. The energy storage control system based on the STM32 single-chip microcomputer can control the two control circuit breakers to change the switch state when receiving the switch switching signal, and switch the energy storage battery used for energy supply. The two control circuit breakers cannot be closed at the same time to avoid the occurrence of power circulation.

[0035] Embodiment 2:

[0036] See also Figure 1 - Figure 2 As shown, the battery life monitoring unit collects the charging and discharging behaviors of the energy storage battery, and numbers each charging and discharging number as i, i=1, 2, 3..., n. At the same time, the battery life monitoring unit counts the battery charging rate and battery discharging rate in each charging and discharging process, and counts from the beginning of the battery charging and discharging to the completion of the battery charging and discharging. The charging rate or discharge rate obtained in the charging and discharging process is arithmetic averaged, and the average value is recorded as the average charging rate ci or the average discharge rate pi. The battery life monitoring unit obtains the battery cycle characteristic value X through formula analysis. Wherein q is a preset weight coefficient, and the value range of q is 2 to 2.15. When the battery is in a charging state for the i-th time, pi is recorded as 0, and when the battery is in a discharging state for the i-th time, ci is recorded as 0. The battery life supervision unit uses the battery cycle characteristic value as the equivalent number of charge and discharge times. At the same time, the battery life supervision unit records the battery cycle characteristic values ​​of the two groups of energy storage batteries as the first battery charge and discharge times and the second battery charge and discharge times, respectively. The battery life supervision unit obtains the preset warranty charge and discharge times, divides the first battery charge and discharge times by the preset warranty charge and discharge times, and records it as the first battery charge and discharge rate, and divides the second battery charge and discharge times by the preset warranty charge and discharge times, and records it as the second battery charge and discharge rate;

[0037] The battery life monitoring unit records the installation time of the battery, and records the installed time of the two sets of energy storage batteries as the first battery usage time and the second battery usage time. The battery life monitoring unit obtains the warranty time of the battery, and divides the first battery usage time by the warranty time to obtain the first battery usage rate, and divides the second battery usage time by the warranty time to obtain the second battery usage rate;

[0038] The battery life monitoring unit calculates the difference between the first battery usage rate and the first battery charge and discharge rate, and records it as the first battery difference rate; calculates the difference between the second battery usage rate and the second battery charge and discharge rate, and records it as the second battery difference rate; the battery life monitoring unit compares the first battery difference rate with the second battery difference rate, and records a larger group of batteries in the comparison result as large-difference batteries; sends the large-difference batteries to the power switching control unit; after the power switching control unit obtains the large-difference batteries, it records the large-difference batteries as energy supply batteries, and supplies power through the large-difference batteries to increase the number of charge and discharge times of the large-difference batteries, so that the number of charge and discharge times and the use time of the large-difference batteries can reach the warranty period as much as possible at the same time, avoiding the situation where the use time reaches the warranty period but the number of charge and discharge times is still far from the warranty number, or the number of charge and discharge times reaches the warranty number but the use time is far from the warranty period, thereby improving the economy of maintenance or replacement.

[0039] Embodiment three:

[0040] See also Figure 1 - Figure 2 As shown, the battery status analysis unit collects the operating status of the energy storage battery, and the operating status of the energy storage battery includes the operating temperature and the operating stability. The battery status analysis unit obtains a preset temperature standard range, and records the collected operating temperatures of the two groups of energy storage batteries as the first battery temperature and the second battery temperature, respectively. The first battery temperature and the second battery temperature are compared with the preset temperature standard range, respectively. If the temperature is outside the preset temperature standard range, the value of the temperature exceeding the temperature standard range is calculated and recorded as the temperature exceeding rate. If the temperature is within the preset temperature standard range, the temperature exceeding rate is 0, and the value obtained by the first battery temperature calculation is recorded as the first temperature exceeding rate, and the value obtained by the second battery temperature calculation is recorded as the second temperature exceeding rate.

[0041] The battery state analysis unit detects the output power and input power of the energy storage battery, with an interval of 1 second between two adjacent detections, and records the output power difference between two adjacent output power detections as the output variation value, and records the input power difference between two adjacent input power detections as the input variation value. The battery state analysis unit averages the output variation value and the input variation value of the energy storage battery to obtain an average operation fluctuation, and records the average operation fluctuations of the two groups of energy storage batteries as the first operation fluctuation and the second operation fluctuation, respectively.

[0042] The battery status analysis unit compares the first temperature exceedance rate with the second temperature exceedance rate, records the energy storage battery with a larger temperature exceedance rate as an abnormal battery, and sends the abnormal battery to the power switching control unit. The battery status analysis compares the first operation fluctuation with the second operation fluctuation, records the energy storage battery with a larger operation fluctuation as a fluctuating battery, and sends the fluctuating battery to the power switching control unit.

[0043] After the power switching control unit obtains an abnormal battery or a fluctuating battery, it generates an abnormal reminder signal, and sends the abnormal reminder signal to the management personnel and management equipment through the network, and displays the reminder on the display screen. If the abnormal battery and the fluctuating battery are the same battery, a battery shutdown signal is generated at the same time as the abnormal reminder signal, and the abnormal and fluctuating battery is stopped from operating, and switched to another group of batteries for operation, and a maintenance reminder is generated at the same time.

[0044] Embodiment 4:

[0045] See also Figure 1 - Figure 2As shown, the battery usage statistics unit can obtain the batteries that are currently in working state in real time, and count the usage time of the batteries in working state, and calculate the operating time proportion of the two groups of energy storage batteries respectively by dividing the cumulative usage time of a single group of batteries by the total usage time, and send the operating time proportion to the management personnel, so that the management personnel can understand the usage status of the two groups of batteries and perform targeted maintenance work during maintenance.

[0046] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. An intelligent energy storage system suitable for a non-return bidirectional switching power supply, characterized in that: A load monitoring unit is included, which is used to monitor the load of the energy storage power supply and balance the power of the energy storage power supply with the load of the energy storage power supply; A power switching control unit, which can control the use of the battery, switch the working state of the battery, and issue an early warning reminder for abnormal batteries; A battery usage statistics unit, which can collect statistics on battery usage and upload the statistics via a network; A battery status analysis unit, which can collect operating parameters of the battery, analyze the operating status of the battery according to the operating parameters, generate analysis results and send them to the power switching control unit; A battery life monitoring unit, which can perform statistical analysis on the number of times the battery is charged and discharged and the usage of the battery, and determine whether the number of times the battery is charged and discharged and the usage time are balanced according to the analysis results; The battery life monitoring unit analyzes the number of times of charging and discharging and the usage of the battery as follows: Step 1: The battery life monitoring unit records the installation time of the battery, and records the installed time of the two sets of energy storage batteries as the first battery usage time and the second battery usage time. The battery life monitoring unit obtains the warranty time of the battery, and divides the first battery usage time by the warranty time to obtain the first battery usage rate, and divides the second battery usage time by the warranty time to obtain the second battery usage rate; Step 2: The battery life monitoring unit collects the charge and discharge behavior of the energy storage battery, analyzes the charge and discharge rate and the number of charge and discharge times, and obtains the first battery charge and discharge rate and the second battery charge and discharge rate respectively; Step 3: The battery life monitoring unit calculates the difference between the first battery usage rate and the first battery charge and discharge rate, and records it as the first battery difference rate. The battery life monitoring unit calculates the difference between the second battery usage rate and the second battery charge and discharge rate, and records it as the second battery difference rate. The battery life monitoring unit compares the first battery difference rate with the second battery difference rate, and records the larger group of batteries in the comparison result as large-difference batteries, and sends the large-difference batteries to the power switching control unit. After the power switching control unit obtains the large-difference batteries, it records the large-difference batteries as energy supply batteries, and supplies power through the large-difference batteries. The method for the battery life monitoring unit to obtain the first battery charge and discharge rate and the second battery charge and discharge rate is: The battery life monitoring unit collects the charging and discharging behaviors of the energy storage battery. At the same time, the battery life monitoring unit counts the battery charging rate and battery discharging rate in each charging and discharging process, and starts timing when the battery charging and discharging starts and ends when the battery charging and discharging is completed. The charging rate or discharge rate obtained during the charging and discharging process is arithmetic averaged, and the average value is recorded as the average charging rate or the average discharge rate. The battery life monitoring unit obtains the battery cycle characteristic value through formula analysis. When the battery is in a charging state, the average discharge rate is recorded as 0, and when the battery is in a discharging state, the average charging rate is recorded as 0. The battery life monitoring unit uses the battery cycle characteristic value as an equivalent number of charges and discharges. At the same time, the battery life monitoring unit records the battery cycle characteristic values ​​of the two groups of energy storage batteries as the first battery charge and discharge number and the second battery charge and discharge number, respectively. The battery life monitoring unit obtains the preset warranty charge and discharge number, divides the first battery charge and discharge number by the preset warranty charge and discharge number, and records it as the first battery charge and discharge rate, and divides the second battery charge and discharge number by the preset warranty charge and discharge number, and records it as the second battery charge and discharge rate.

2. The intelligent energy storage system suitable for a non-return bidirectional switching power supply according to claim 1, characterized in that: The load monitoring unit is preset with a power load threshold. The load monitoring unit compares the power load of the energy storage power supply with the different power load thresholds preset by the load monitoring unit. If the power load of the energy storage power supply is less than the preset power load threshold, the energy storage power supply is operated in a low-power state. If the power load of the energy storage power supply is greater than or equal to the preset power load threshold, the energy storage power supply is operated in a high-power state.

3. The intelligent energy storage system suitable for a non-return bidirectional switching power supply according to claim 1, characterized in that: The battery status analysis unit collects the operating status of the energy storage battery, the operating status of the energy storage battery includes the operating temperature and the operating stability. The battery status analysis unit obtains a preset temperature standard range, and records the collected operating temperatures of the two groups of energy storage batteries as a first battery temperature and a second battery temperature, respectively, and compares the first battery temperature and the second battery temperature with the preset temperature standard range, respectively. If the temperature is outside the preset temperature standard range, the value of the temperature exceeding the temperature standard range is calculated and recorded as the temperature exceeding rate. If the temperature is within the preset temperature standard range, the temperature exceeding rate is 0, and the value obtained by the first battery temperature calculation is recorded as the first temperature exceeding rate, and the value obtained by the second battery temperature calculation is recorded as the second temperature exceeding rate; The battery state analysis unit detects the output power and input power of the energy storage battery, records the output power difference between two adjacent output power detections as the output variation value, and records the input power difference between two adjacent input power detections as the input variation value. The battery state analysis unit averages the output variation value and the input variation value of the energy storage battery to obtain an average operation fluctuation, and records the average operation fluctuations of the two groups of energy storage batteries as a first operation fluctuation and a second operation fluctuation, respectively. The battery status analysis unit compares the first temperature exceedance rate with the second temperature exceedance rate, records the energy storage battery with a larger temperature exceedance rate as an abnormal battery, and sends the abnormal battery to the power switching control unit. The battery status analysis compares the first operation fluctuation with the second operation fluctuation, records the energy storage battery with a larger operation fluctuation as a fluctuating battery, and sends the fluctuating battery to the power switching control unit.

4. The intelligent energy storage system for a non-return bidirectional switching power supply according to claim 1, characterized in that: After the power switching control unit obtains an abnormal battery or a fluctuating battery, it generates an abnormal reminder signal. If the abnormal battery and the fluctuating battery are the same battery, a battery shutdown signal is generated at the same time as the abnormal reminder signal, and the abnormal and fluctuating battery is stopped from operating and switched to another group of batteries for operation.

5. The intelligent energy storage system suitable for a non-return bidirectional switching power supply according to claim 1, characterized in that: The battery usage statistics unit can obtain the batteries currently in working state in real time, count the usage time of the batteries in working state, and calculate the operating time proportion of the two groups of energy storage batteries respectively by dividing the accumulated usage time of a single group of batteries by the total usage time.

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