Intelligent lithium battery system with self-adaptive charging and discharging management

Abstract

The invention relates to the technical field of lithium battery management, in particular to a self-adaptive charging and discharging management intelligent lithium battery system which comprises a self-adaptive discharging module and a self-adaptive charging module. The self-adaptive discharge module is used for controlling the discharge mode of the lithium battery, the self-adaptive discharge module configures a self-adaptive voltage offset Vooffset through a cloud end, the self-adaptive discharge module provides an intelligent lithium battery BMS system, the voltage offset Vooffset is issued to the intelligent lithium battery BMS system through the internet, and the intelligent lithium battery BMS reads the current output bus voltage VBus. Self-adaptive discharging can avoid unstable discharging power caused by unstable busbar voltage due to power grid jitter, maintenance personnel can conveniently adjust output voltage of the rectifier module according to load requirements, and normal discharging of the battery is not affected by variation of busbar voltage. Adaptive charging can automatically match suitable charging power and duration according to peak-valley electricity price time period requirements, so as to maximize energy management, achieve the purpose of more charging at valley price and more discharging at peak price, and maximize energy management benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery management, and specifically to an intelligent lithium battery system with adaptive charge and discharge management. Background Technique

[0002] For the traditional charge and discharge management of battery packs, the method is relatively single and cannot dynamically adjust the suitable charge and discharge power according to grid fluctuations and load changes; for example, during discharge, as Figure 2 shown, it is usually a constant voltage output, which limits the maximum power and maximum current output of the battery. If the bus voltage is lower than the battery command voltage and the load power >= the battery power, the battery can discharge at full power; but when there are other power sources providing energy on the busbar, the busbar voltage may be higher than or equal to the battery output given voltage. If the traditional method is still used for discharge, the battery pack cannot discharge electrical energy or the discharge power is very small, and the expected effect cannot be achieved, thus limiting the energy management of the battery pack.

[0003] During the charging stage, as Figure 3 shown, the traditional method is constant current charging, and it switches to constant voltage floating charge at the end of charging. With a certain charging current, the charging time is fixed. For scenarios with peak-valley-flat electricity prices, it is necessary to dynamically adjust the charge and discharge power and time in real time according to the electricity consumption situation, and perform energy management in an optimal way to achieve maximum benefits. Therefore, the traditional method cannot achieve this purpose. Summary of the Invention

[0004] The purpose of the present invention is to provide an intelligent lithium battery system with adaptive charge and discharge management to solve the problems raised in the above background technique.

[0005] To achieve the above purpose, the present invention provides the following technical solution: An intelligent lithium battery system with adaptive charge and discharge management, including an adaptive discharge module and an adaptive charging module; The adaptive discharge module is used to control the discharge mode of the lithium battery. The adaptive discharge module configures the adaptive voltage offset VoOffset through the cloud. The adaptive discharge module provides an intelligent lithium battery BMS system, and the voltage offset VoOffset is sent to the intelligent lithium battery BMS system through the Internet. The intelligent lithium battery BMS reads the current output bus voltage VBus, generates an adaptive variable VoRef, and injects VoRef into the power conversion regulator. The power regulator adjusts the power output according to the command voltage; The adaptive charging module is used to control the switching between the charging and discharging states of the lithium battery.

[0006] Preferably, the adaptive variable VoRef = VoOffset + VBus.

[0007] Preferably, in the adaptive discharge module, regardless of the change in the bus voltage VBus, the intelligent lithium power regulator always outputs a discharge at a fixed voltage difference VoOffset, thereby ensuring that the lithium battery can always be discharged and achieving the expected energy management objective.

[0008] Preferably, the adaptive charging module controls the lithium battery to charge more during the valley price period, discharge more during the peak price period, and charge appropriately during the flat price period. The flat price charging automatically adapts, so that the charged amount is just discharged during the subsequent discharge. When the SoC reaches 0, it enters the next valley price charging stage to achieve optimal energy management and maximize the benefits.

[0009] Preferably, when the intelligent lithium battery charge state is SoC1 after charging during the valley price charging stage T1 and the charge state is SoC2 after discharging during the discharging stage T3, the remaining dischargeable amount is: LiCap·(SoC1 - SoC2) where LiCap is the total battery capacity; If the discharge power is Pout and the discharge voltage is Vout, the remaining dischargeable duration is: TimeLeft = LiCap·(SoC1 - SoC2)·Vout / Pout If TimeLeft is greater than the duration T5 of the second discharge stage, no charging is required; otherwise, charging is required. If T5 is greater than TimeLeft, the charging amount required is: ChargeCap = (T5 - TimeLeft)·Pout / Vout The charging current ICharge is: ICharge = ChargeCap / T4, where ICharge is not greater than the maximum chargeable current IChargeMax.

[0010] Compared with the prior art, the beneficial effects of the present invention are: 1. Adaptive discharge can be immune to the unstable discharge power caused by the grid jitter affecting the unstable bus voltage, and it is also convenient for maintenance personnel to adjust the output voltage of the rectifier module (AC / DC) according to the load demand. The change in the bus voltage does not affect the normal discharge of the battery.

[0011] 2. Adaptive charging can automatically match the appropriate charging power and duration according to the requirements of the peak-valley electricity price time period to maximize the optimization of energy management, achieve the purpose of charging more during the valley price and discharging more during the peak price, and thus maximize the energy management benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a block diagram of the charge and discharge management system.

[0013] Figure 2 It is a schematic diagram of the traditional discharge process.

[0014] Figure 3 It is a schematic diagram of the traditional charging process.

[0015] Figure 4 It is a schematic diagram of the adaptive discharge process of the present invention.

[0016] Figure 5 It is the peak-valley-flat electricity price and charge-discharge timing diagram of the present invention.

[0017] Figure 6 It is a schematic diagram of the adaptive charging process of the present invention. Detailed implementation manners

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0019] Please refer to Figures 1 to 6 , the present invention provides a technical solution: an intelligent lithium battery system for adaptive charge and discharge management, including an adaptive discharge module and an adaptive charging module; The adaptive discharge module is used to control the discharge mode of the lithium battery. The adaptive discharge module configures the adaptive voltage offset VoOffset through the cloud. The adaptive discharge module provides an intelligent lithium battery BMS system. The voltage offset VoOffset is sent to the intelligent lithium battery BMS system through the Internet. The intelligent lithium battery BMS reads the current output bus voltage VBus and generates an adaptive variable VoRef. The adaptive variable VoRef = VoOffset + VBus (variable). Inject VoRef into the power conversion regulator, and the power regulator adjusts the power output according to the command voltage; in the adaptive discharge module, regardless of how the bus voltage VBus changes, the intelligent lithium battery power regulator always discharges at a fixed pressure difference VoOffset, so as to ensure that the lithium battery can always be discharged and achieve the expected energy management purpose.

[0020] The adaptive charging module is used to control the switching between the charging and discharging states of the lithium battery. The adaptive charging module controls the lithium battery to charge more at valley prices, discharge more at peak prices, and charge appropriately at flat prices. The flat-price charging adapts automatically, so that the charged amount is just discharged in the subsequent discharge. When the SoC is 0, it enters the next valley-price charging stage to achieve optimal energy management and maximize the benefits.

[0021] After the lithium battery is charged in the valley price charging stage T1, the intelligent lithium charge state of charge is SoC1. After discharging in the discharging stage T3, the state of charge is SoC2. Then the remaining dischargeable amount is: LiCap·(SoC1 - SoC2) Where LiCap is the total battery capacity; If the discharge power is Pout and the discharge voltage is Vout, then the remaining dischargeable time is: TimeLeft = LiCap·(SoC1 - SoC2)·Vout / Pout If TimeLeft is greater than the duration T5 of the second discharge stage, then no charging is required. Otherwise, charging is required; If T5 is greater than TimeLeft, then the charging amount required is: ChargeCap = (T5 - TimeLeft)·Pout / Vout The charging current ICharge is: ICharge = ChargeCap / T4, Where ICharge is not greater than the maximum chargeable current IChargeMax.

[0022] An intelligent lithium battery system with adaptive charge and discharge management proposed by the present invention. The adaptive discharge can be immune to the unstable discharge power caused by the grid jitter to the unstable bus voltage, and it is also convenient for maintenance personnel to adjust the output voltage of the rectifier module (AC / DC) according to the load demand. According to the bus voltage, the offset voltage is automatically superimposed, and the constant voltage value of the battery output is dynamically set. The discharge current is less than the threshold, and the bus voltage is dynamically detected. The adaptive discharge output constant voltage value, and the change of the bus voltage does not affect the normal discharge of the battery. During charging, according to the future discharge demand, the charging current and power are adapted. The adaptive charging can automatically match the appropriate charging power and duration according to the requirements of the peak-valley electricity price time period, so as to maximize the optimization of energy management, achieve the purpose of charging more at valley prices and discharging more at peak prices, and thus maximize the energy management benefit.

[0023] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made in these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent lithium battery system with adaptive charge and discharge management, characterized in that: It includes an adaptive discharge module and an adaptive charging module; The adaptive discharge module is used to control the discharge mode of the lithium battery. The adaptive discharge module configures the adaptive voltage offset VoOffset through the cloud. The adaptive discharge module provides an intelligent lithium battery BMS system. The voltage offset VoOffset is sent to the intelligent lithium battery BMS system through the Internet. The intelligent lithium battery reads the current output bus voltage VBus, generates an adaptive variable VoRef, and injects VoRef into the power conversion regulator. The power regulator adjusts the power output according to the command voltage; The adaptive charging module is used to control the switching between the charging and discharging states of the lithium battery.

2. The intelligent lithium battery system with adaptive charge and discharge management according to claim 1, characterized in that: The adaptive variable VoRef = VoOffset + VBus.

3. An intelligent lithium battery system with adaptive charge and discharge management according to claim 1, characterized in that: In the adaptive discharge module, regardless of how the busbar voltage VBus changes, the intelligent lithium battery power regulator always discharges at a fixed voltage difference VoOffset, so as to ensure that the lithium battery can always be discharged, achieving the expected energy management goal.

4. An intelligent lithium battery system with adaptive charge and discharge management according to claim 1, characterized in that: The adaptive charging module controls the lithium battery to charge more during valley prices, discharge more during peak prices, and charge appropriately during flat prices. The flat-price charging adapts automatically, so that the charged amount is just discharged in the subsequent discharge. When the SoC reaches 0, it enters the next valley-price charging stage, achieving optimal energy management and maximizing the benefits.

5. An intelligent lithium battery system with adaptive charge and discharge management according to claim 1, characterized in that: After the lithium battery is charged during the valley-price charging stage T1, the state of charge of the intelligent lithium battery is SoC1. After discharging during the discharge stage T3, the state of charge is SoC2. Then the remaining dischargeable amount is: LiCap·(SoC1 - SoC2) where LiCap is the total battery capacity; If the discharge power is Pout and the discharge voltage is Vout, then the remaining dischargeable duration is: TimeLeft = LiCap·(SoC1 - SoC2)·Vout / Pout If TimeLeft is greater than the duration T5 of the second discharge stage, then no charging is required. Otherwise, charging is required; If T5 is greater than TimeLeft, then the charging amount required is: ChargeCap = (T5 - TimeLeft)·Pout / Vout The charging current ICharge is: ICharge = ChargeCap / T4, where ICharge is not greater than the maximum rechargeable current IChargeMax.

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