CN117895135A - Modular liquid-cooled battery energy storage and intelligent power distribution system - Google Patents

Abstract

The invention discloses a modularized liquid cooling battery energy storage and intelligent power distribution system, which comprises a plurality of battery energy storage units, wherein each unit is provided with a liquid cooling circulation system, and the system comprises cooling liquid, a circulating pump and a cooling pipeline and is used for effectively controlling the temperature of the battery unit. Each battery energy storage unit consists of a plurality of battery modules and can work independently or jointly. The system also comprises an intelligent power distribution system which is composed of a data acquisition unit, a control unit and a communication unit, and realizes battery management, temperature control and remote monitoring. The control unit adopts a strategy based on a PID control algorithm to optimize temperature regulation and system efficiency.

Description

Modular liquid-cooled battery energy storage and intelligent power distribution system

Technical Field

The present invention relates to the field of power distribution technology, and in particular to a modular liquid-cooled battery energy storage and intelligent power distribution system.

Background technique

In existing power storage and management systems, the efficiency and life of batteries are often affected by improper temperature control and inadequate management. Traditional battery energy storage systems often use air cooling or do not have efficient thermal management mechanisms, which causes the battery to overheat easily when running at high loads, affecting battery performance and life. At the same time, the traditional power distribution system lacks intelligent management and cannot effectively respond to fluctuations in power demand, especially in the context of the increasing popularity of renewable energy such as solar and wind power, the stability and efficiency of the power grid has become an important challenge.

The existing technology faces the following core difficulties:

1. Insufficient temperature control: Traditional battery energy storage systems rely heavily on air cooling, which is not very efficient. Batteries operating in high temperature environments are prone to accelerated aging. 2. Imprecise battery management: The lack of an effective battery management system makes it difficult to monitor and optimize the battery status in real time, affecting battery efficiency and life. 3. Low power distribution efficiency: Traditional power distribution systems lack flexibility in dealing with peak and trough power demand and cannot efficiently utilize renewable energy. 4. Difficulty in maintenance and expansion: The non-modular design of the system makes maintenance and expansion costs high and has poor flexibility. Therefore, how to provide a modular liquid-cooled battery energy storage and intelligent distribution system to solve these problems in the prior art is an urgent problem that technicians in the field of power storage and management need to solve.

Summary of the invention

One object of the present invention is to propose a modular liquid-cooled battery energy storage and intelligent power distribution system. The present invention makes full use of modular design concepts, liquid cooling technology and intelligent power management technology, and describes in detail how to effectively perform battery temperature control, battery management, and power distribution and scheduling. The system is easy to expand and maintain through modular design, and the liquid cooling method effectively reduces the battery temperature and improves battery efficiency and reliability. At the same time, the system also adopts an intelligent power distribution system to achieve remote monitoring and control and improve system operation efficiency. While ensuring the stability and safety of power supply, the present invention has the advantages of high efficiency, strong reliability and intelligent management.

A modular liquid-cooled battery energy storage and intelligent power distribution system according to an embodiment of the present invention comprises the following steps:

Multiple battery energy storage units, each battery energy storage unit is equipped with a liquid cooling circulation system for controlling the temperature of the battery unit, the liquid cooling circulation system comprising: a coolant, a circulation pump, and a cooling pipeline for heat exchange with the battery unit;

Each battery energy storage unit is composed of several battery modules. Each battery module contains multiple battery cells. Each battery energy storage unit can work independently or in conjunction with other units. The temperature control of the battery cells follows:

Where T _new is the updated battery temperature, T _old is the current battery temperature, P _dissipated is the power dissipated by the battery cell, Δt is the time interval, C _thermal is the specific heat capacity of the battery cell, and m is the mass of the battery cell;

An intelligent power distribution system is used to manage and monitor the working status of a battery energy storage unit. The intelligent power distribution system includes a data acquisition unit, a control unit, and a communication unit. The data acquisition unit is responsible for collecting data such as voltage, current, and temperature of the battery unit. The control unit performs battery charge and discharge management, temperature control, and fault diagnosis functions based on the collected data. The communication unit is responsible for data interaction with an external system for remote monitoring and control. The control unit of the intelligent power distribution system adopts a temperature regulation strategy based on a PID control algorithm.

Optionally, each of the battery energy storage units is equipped with a dedicated battery management system, which is used to monitor the charge and discharge status of each battery cell in real time, measure the real-time voltage and current of the battery cell, and monitor the temperature of the battery cell. The battery management system calculates the state of charge of the battery cell:

Among them, SOC(t) represents the state of charge at time t, SOC(t-1) represents the state of charge at time t-1, I represents the average charge and discharge current in the time interval Δt, Q _total represents the nominal total power of the battery cell, and the battery management system evaluates the health state (SOH) of the battery cell:

Among them, Q _available represents the current effective power of the battery unit, and Q _total is the original total power of the battery unit;

Optionally, each battery energy storage unit of the system is equipped with an independent liquid cooling circulation system; the liquid cooling circulation system is composed of a coolant circulation pump, a coolant storage container and a cooling pipeline directly in contact with the battery unit;

The system automatically adjusts the flow of coolant:

Wherein, Q _coolant is the required coolant flow rate, P _dissipated is the heat power dissipated by the battery cell, c _p is the specific heat capacity of the coolant, and ΔT _coolant is the temperature difference when the coolant enters and leaves the battery cell; the temperature control unit of the liquid cooling circulation system adjusts the temperature and flow rate of the coolant according to the real-time temperature and power output of the battery cell, and the battery cell operates at its optimal operating temperature.

Optionally, the intelligent power distribution system in the system has energy distribution and load management functions, and has the function of adjusting the charging and discharging of each battery energy storage unit in real time according to the grid demand and the status of the battery energy storage unit;

Optimal charging and discharging strategy for battery energy storage units:

Where P _output,i represents the output power of the i-th battery energy storage unit, P _demand is the current total power demand of the system, SOC _i is the state of charge of the i-th battery energy storage unit, n is the total number of battery energy storage units, is the sum of the state of charge of all battery energy storage units, η(T _battery,i ,SOC _i C _i )

To consider the efficiency function of battery temperature and state of charge, the efficiency function η(T _battery,i , SOC _i ) is adjusted according to the temperature T _battery,i and the state of charge SOC _i of the i-th battery cell, thereby ensuring long-term use of the battery.

Optionally, each of the battery energy storage units is equipped with an independent thermal management system, which has the function of regulating the flow and temperature of the coolant according to the specific working conditions of the battery unit and the ambient temperature;

The thermal management system includes a temperature sensor, a flow control valve and a temperature control unit. The temperature sensor monitors the real-time temperature of the battery unit, and the flow control valve adjusts the flow rate of the coolant according to the temperature data.

Adjust the coolant temperature:

T _coolant,out = T _ambient + (T _battery,opt - T _ambient ) × K

Wherein, T _coolant,out is the output temperature of the coolant, T _ambient is the ambient temperature, T _battery,opt is the optimal operating temperature of the battery unit, and K is the adjustment coefficient.

Optionally, the intelligent power distribution system has an energy optimization and allocation function, which optimizes the charging and discharging process of the battery energy storage unit through an algorithm;

The energy optimization allocation function adopts the algorithm:

Where P _opt,i is the optimal output power of the i-th battery energy storage unit, SOC _i and SOH _{i are} the state of charge and health state of the unit respectively, n is the total number of battery energy storage units, P _demand is the total power demand of the system, and η(T _battery,i ) is the efficiency function adjusted according to the temperature T _battery,i of the i-th battery unit.

Optionally, each of the battery energy storage units has a built-in high-precision fault detection and diagnosis mechanism, which is designed to monitor the working status of the battery unit in real time and identify potential battery failures, including internal short circuit, overcharge, over discharge and thermal runaway;

The fault detection and diagnosis mechanism calculates fault indicators based on the following algorithm, combining the real-time voltage, current and temperature data of the battery cell:

F _index,i = w ₁ × ΔV _i + w ₂ × ΔI _i + w ₃ × ΔT _i

Wherein, F _index,i is the fault index of the i-th battery cell, ΔV _i , ΔI _i and ΔT _i represent the voltage, current and temperature deviations of the battery cell relative to its normal working state, respectively, w ₁ , w ₂ and w ₃ are corresponding weight coefficients, reflecting the contribution of different deviations to the fault index. The fault detection mechanism immediately triggers an alarm when an abnormal deviation is identified, and initiates corresponding emergency measures according to the nature and severity of the fault.

Optionally, each of the battery energy storage units includes a high-efficiency energy recovery mechanism designed to collect and recover energy during battery discharge;

Efficient energy recovery mechanism:

Wherein, E _recovered represents the total amount of energy recovered in the time interval t ₁ to t ₂ , P _discharge (t) is the discharge power of the battery unit at time t, η _recovery is the energy recovery efficiency, which represents the efficiency loss in the energy conversion process. The energy conversion module has the function of storing the recovered energy in the form of electrical energy or directly transferring it to the power grid or other battery units.

The beneficial effects of the present invention are:

The modular liquid-cooled battery energy storage and intelligent power distribution system introduced in this patent is an innovative energy solution, mainly used to improve the efficiency and stability of power grids and renewable energy systems. The system adopts a modular design and is equipped with an efficient liquid cooling system and an advanced battery management system to effectively reduce the operating temperature of the battery, extend battery life, and improve overall reliability. The intelligent power distribution control unit automatically adjusts the charging and discharging strategy through optimization algorithms to achieve efficient use of energy, and supports remote monitoring and control to make system operation and maintenance more efficient. This patent has significant advantages in improving energy efficiency, enhancing system safety, optimizing operation and maintenance management, and supporting environmental sustainability, showing broad application potential and market value.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

FIG1 is a schematic diagram of a modular liquid-cooled battery energy storage and intelligent power distribution system according to the present invention.

Detailed ways

The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

Refer to Figure 1 to see how the battery energy storage unit, liquid cooling circulation system and intelligent power distribution system work together, describing the interconnection and data flow between the various system parts.

In this embodiment, multiple battery energy storage units, each battery energy storage unit is equipped with a liquid cooling circulation system for controlling the temperature of the battery unit, and the liquid cooling circulation system includes: a coolant, a circulation pump, and a cooling pipeline for heat exchange with the battery unit;

Each battery energy storage unit is composed of several battery modules. Each battery module contains multiple battery cells. Each battery energy storage unit can work independently or in conjunction with other units. The temperature control of the battery cells follows:

Where T _new is the updated battery temperature, T _old is the current battery temperature, P _dissipated is the power dissipated by the battery cell, Δt is the time interval, C _thermal is the specific heat capacity of the battery cell, and m is the mass of the battery cell;

An intelligent power distribution system is used to manage and monitor the working status of a battery energy storage unit. The intelligent power distribution system includes a data acquisition unit, a control unit, and a communication unit. The data acquisition unit is responsible for collecting data such as voltage, current, and temperature of the battery unit. The control unit performs battery charge and discharge management, temperature control, and fault diagnosis functions based on the collected data. The communication unit is responsible for data interaction with an external system for remote monitoring and control. The control unit of the intelligent power distribution system adopts a temperature regulation strategy based on a PID control algorithm.

In this embodiment, each of the battery energy storage units is equipped with a dedicated battery management system, which is used to monitor the charge and discharge status of each battery unit in real time, measure the real-time voltage and current of the battery unit, and monitor the temperature of the battery unit;

The battery management system calculates the state of charge of the battery cells:

Wherein, SOC(t) represents the state of charge at time t, SOC(t-1) represents the state of charge at time t-1, I represents the average charge and discharge current in the time interval Δt, and Q _total represents the nominal total power of the battery unit;

In this embodiment, the battery management system evaluates the health status of the battery cells:

Among them, Q _available represents the current effective power of the battery unit, and Q _total is the original total power of the battery unit;

Each battery energy storage unit of the system is equipped with an independent liquid cooling circulation system; the liquid cooling circulation system is composed of a coolant circulation pump, a coolant storage container and a cooling pipeline directly in contact with the battery unit;

The system automatically adjusts the flow of coolant:

Wherein, Q _coolant is the required coolant flow rate, P _dissipated is the heat power dissipated by the battery cell, c _p is the specific heat capacity of the coolant, and ΔT _coolant is the temperature difference when the coolant enters and leaves the battery cell; the temperature control unit of the liquid cooling circulation system adjusts the temperature and flow rate of the coolant according to the real-time temperature and power output of the battery cell, and the battery cell operates at its optimal operating temperature.

The intelligent power distribution system in the system has energy distribution and load management functions, and has the function of adjusting the charging and discharging of each battery energy storage unit in real time according to the grid demand and the status of the battery energy storage unit;

Optimal charging and discharging strategy for battery energy storage units:

Where P _output,i represents the output power of the i-th battery energy storage unit, P _demand is the current total power demand of the system, SOC _i is the state of charge of the i-th battery energy storage unit, n is the total number of battery energy storage units, is the sum of the states of charge of all battery energy storage units, η(T _battery,i , SOC _i C _i ) is the efficiency function considering the battery temperature and state of charge. The efficiency function η(T _battery,i , SOC _i ) is adjusted according to the temperature T _battery,i and the state of charge SOC _i of the i-th battery unit to ensure long-term use of the battery.

Each of the battery energy storage units is equipped with an independent thermal management system, which has the function of regulating the flow and temperature of the coolant according to the specific working conditions and ambient temperature of the battery unit;

The thermal management system includes a temperature sensor, a flow control valve and a temperature control unit. The temperature sensor monitors the real-time temperature of the battery unit, and the flow control valve adjusts the flow rate of the coolant according to the temperature data.

Adjust the coolant temperature:

T _coolant,out = T _ambient + (T _battery,opt - T _ambient ) × K

Wherein, T _coolant,out is the output temperature of the coolant, T _ambient is the ambient temperature, T _battery,opt is the optimal operating temperature of the battery unit, and K is the adjustment coefficient.

In this implementation, the energy optimization allocation function uses an algorithm:

Wherein, P _opt,i is the optimal output power of the i-th battery energy storage unit, SOC _i and SOH _i are the state of charge and health state of the unit respectively, n is the total number of battery energy storage units, P _demand is the total power demand of the system, and η(T _battery,i ) is the efficiency function adjusted according to the temperature T _battery,i of the i-th battery unit.

In this embodiment, the fault detection and diagnosis mechanism calculates the fault index based on the following algorithm, combined with the real-time voltage, current and temperature data of the battery cell:

F _index,i = w ₁ × ΔV _i + w ₂ × ΔI _i + w ₃ × ΔT _i

Wherein, F _index,i is the fault index of the i-th battery cell, ΔV _i , ΔI _i and ΔT _i represent the voltage, current and temperature deviations of the battery cell relative to its normal working state, respectively, w ₁ , w ₂ and w ₃ are corresponding weight coefficients, reflecting the contribution of different deviations to the fault index. The fault detection mechanism immediately triggers an alarm when an abnormal deviation is identified, and initiates corresponding emergency measures according to the nature and severity of the fault.

In this embodiment, for the efficient energy recovery mechanism:

Wherein, E _recovered represents the total amount of energy recovered in the time interval t ₁ to t ₂ , P _discharge (t) is the discharge power of the battery unit at time t, η _recovery is the energy recovery efficiency, which represents the efficiency loss in the energy conversion process. The energy conversion module has the function of storing the recovered energy in the form of electrical energy or directly transferring it to the power grid or other battery units.

Embodiment 1:

Scenario description: Shanghai Pudong New Area is a busy commercial and financial center, including multiple high-rise office buildings, luxury shopping malls and entertainment facilities. The daily power demand in the area fluctuates greatly, especially during the business peak hours from 9 am to 6 pm. The commercial buildings in the area are equipped with solar panels with a total capacity of 10 megawatts, but due to the intermittent nature of solar power generation, an efficient power storage and management system is needed to balance supply and demand.

Energy storage: During the day, solar panels generate an average of about 800 kilowatt-hours (kWh) of electricity per hour in clear weather. The average electricity demand in the commercial area during off-peak hours (before 9 a.m. and after 6 p.m.) is 600 kWh per hour. Therefore, the system can store about 200 kWh of excess electricity during these hours.

Temperature management: The liquid cooling system maintains the battery temperature within the optimal operating range of approximately 25°C to 30°C by precisely controlling the coolant flow rate and temperature.

Data monitoring and optimization: Through the optimization algorithm of the intelligent power distribution control unit, the system can intelligently adjust the charging and discharging of the energy storage module according to real-time data and historical usage patterns to ensure sufficient power supply during peak hours.

In a week of clear weather, the system stores a total of about 7 days × 2 hours/day × 200 kWh = 2800 kWh of electricity.

During peak hours, the system releases this stored power to meet additional demand. For example, on a particular weekday, the system released about 1,500 kWh of power during peak hours, effectively reducing the burden on the grid.

Through the application of this system, the commercial district has reduced its dependence on the power grid during peak hours and reduced electricity costs. At the same time, the system has significantly improved the battery life and efficiency through optimized temperature control and battery management. In one year of operation, the commercial district's power supply has become more stable and the overall energy efficiency has increased by about 18%.

This embodiment solves the problems of large fluctuations in electricity demand in commercial areas, heavy burden on the power grid, and low utilization of renewable energy. Through the application of modular liquid-cooled battery energy storage and intelligent power distribution system, not only the use and distribution of electricity is optimized, but also the utilization efficiency of renewable energy is improved, while ensuring the stability and security of power supply. In addition, the modular and intelligent design of the system also facilitates future expansion and upgrading, and has good application prospects and development potential.

Table 1 Data table of Example 1 of modularized liquid-cooled battery energy storage and intelligent power distribution system

Referring to Table 1 above, the key data and system characteristics of this embodiment provide a clear perspective to understand how the system works in a specific scenario and the specific benefits it brings. Through these data, we can clearly see how the system effectively manages and optimizes the power demand of the commercial area, improves energy efficiency, and reduces dependence on the power grid.

Claims (8)

1. A modularized liquid cooling battery energy storage and intelligent power distribution system is characterized by comprising

A plurality of battery energy storage units, each battery energy storage unit being equipped with a liquid cooling circulation system for controlling the temperature of the battery unit, the liquid cooling circulation system comprising: a cooling liquid, a circulating pump and a cooling pipeline for heat exchange with the battery unit;

each battery energy storage unit consists of a plurality of battery modules, each battery module internally comprises a plurality of battery units, each battery energy storage unit can work independently or jointly with other units, and the temperature control of the battery units follows:

Wherein, T _new is the updated battery temperature, T _old is the current battery temperature, P _dissipated is the power dissipated by the battery cell, Δt is the time interval, C _thermal is the specific heat capacity of the battery cell, and m is the mass of the battery cell;

The intelligent power distribution system is used for managing and monitoring the working state of the battery energy storage unit and comprises a data acquisition unit, a control unit and a communication unit, wherein the data acquisition unit is used for collecting voltage, current and temperature data of the battery unit, the control unit is used for executing battery charge and discharge management, temperature control and fault diagnosis functions according to the collected data, the communication unit is used for interacting with data of an external system and used for remote monitoring and control, and the control unit of the intelligent power distribution system adopts a temperature regulation strategy based on a PID control algorithm.

2. The modular liquid cooled battery energy storage and intelligent power distribution system of claim 1, wherein each battery energy storage unit is provided with a special battery management system, and the battery management system is used for monitoring the charge and discharge state of each battery unit, measuring the real-time voltage and current of the battery unit and monitoring the temperature of the battery unit in real time;

the battery management system calculates a state of charge of the battery cells:

Wherein SOC (t) represents the state of charge at time t, SOC (t-1) represents the state of charge at time t-1, I represents the average charge-discharge current over time interval Deltat, and Q _total represents the nominal total charge of the battery cell;

The battery management system evaluates the state of health (SOH) of the battery cells:

Where Q _available represents the current active power of the battery unit, and Q _total is the original total power of the battery unit.

3. The modular liquid cooled battery energy storage and intelligent power distribution system of claim 1, wherein,

Each battery energy storage unit of the system is provided with an independent liquid cooling circulation system; the liquid cooling circulation system consists of a cooling liquid circulation pump, a cooling liquid storage container and a cooling pipeline which is directly contacted with the battery unit;

the system automatically adjusts the flow of the cooling liquid:

Wherein, Q _coolant is the required coolant flow, P _dissipated is the thermal power dissipated by the battery cell, c _p is the specific heat capacity of the coolant, Δt _coolant is the temperature difference of the coolant when entering and exiting the battery cell; the temperature control unit of the liquid cooling circulation system adjusts the temperature and the flow rate of the cooling liquid according to the real-time temperature and the power output of the battery unit, so that the battery unit operates at the optimal working temperature.

4. The modular liquid cooled battery energy storage and intelligent power distribution system of claim 1, wherein,

The intelligent power distribution system in the system has the functions of energy distribution and load management, and has the function of adjusting the charge and discharge of each battery energy storage unit in real time according to the power grid requirements and the states of the battery energy storage units;

Optimal charge-discharge strategy of battery energy storage unit:

Wherein, P _output,i represents the output power of the ith battery energy storage unit, P _demand is the current total power demand of the system, SOC _i is the state of charge of the ith battery energy storage unit, n is the total number of battery energy storage units, is the sum of the states of charge of all battery energy storage units, η (T _battery,i,SOC_iC_i) is an efficiency function considering the battery temperature and the state of charge, and the efficiency function η (T _battery,i,SOC_i) is adjusted according to the temperature T _battery,i and the state of charge SOC _i of the ith battery unit, so that long-time use of the battery is ensured.

5. The modular liquid cooled battery energy storage and intelligent power distribution system of claim 1, wherein each battery energy storage unit is provided with an independent thermal management system, and has the functions of regulating the flow rate and temperature of the cooling liquid under specific working conditions and environmental temperature of the battery unit;

the thermal management system comprises a temperature sensor, a flow control valve and a temperature control unit, wherein the temperature sensor monitors the real-time temperature of the battery unit, and the flow control valve adjusts the flow rate of the cooling liquid according to the temperature data;

Adjusting the temperature of the cooling liquid:

T_coolant,out＝T_ambient+(T_battery,opt-T_ambient)×K

Wherein, T _coolant,out is the output temperature of the cooling liquid, T _ambient is the ambient temperature, T _battery,opt is the optimal working temperature of the battery unit, and K is the adjustment coefficient.

6. The modular liquid-cooled battery energy storage and intelligent power distribution system according to claim 1, wherein the intelligent power distribution system has an energy optimization and allocation function, and the function optimizes the charging and discharging process of a battery energy storage unit through an algorithm;

the energy optimization and allocation function adopts an algorithm:

Wherein, P _opt,i is the optimal output power of the ith battery energy storage unit, SOC _i and SOH _i are the state of charge and state of health of the unit, n is the total number of battery energy storage units, P _demand is the total power requirement of the system, and η (T _battery,i) is the efficiency function adjusted according to the temperature T _battery,i of the ith battery unit.

7. The modular liquid cooled battery energy storage and intelligent power distribution system of claim 1, wherein each battery energy storage unit incorporates a fault detection and diagnosis mechanism with high accuracy aimed at monitoring the operating state of the battery unit in real time and identifying potential battery faults, including internal short circuit, overcharge, overdischarge, and thermal runaway conditions;

the fault detection and diagnosis mechanism calculates a fault index according to the following algorithm by combining real-time voltage, current and temperature data of the battery unit:

F_index,i＝w₁×ΔV_i+w₂×ΔI_i+w₃×ΔT_i

Wherein F _index,i is a fault index of the ith battery unit, deltaV _i、ΔI_i and DeltaT _i respectively represent voltage, current and temperature deviations of the battery unit relative to a normal working state of the battery unit, w ₁、w₂ and w ₃ are corresponding weight coefficients, contribution degrees of different deviations to the fault index are reflected, and when an abnormal deviation is identified, the fault detection mechanism immediately triggers an alarm and starts corresponding emergency measures according to the nature and severity of the fault.

8. The modular liquid cooled battery energy storage and intelligent power distribution system of claim 1, wherein each of said battery energy storage units comprises a high energy recovery mechanism aimed at collecting and recovering energy during battery discharge, the high energy recovery mechanism:

Wherein E _recovered represents the total amount of energy recovered in the time interval t ₁ to t ₂, P _discharge (t) is the discharge power of the battery unit at time t, η _recovery is the energy recovery efficiency, representing the efficiency loss during energy conversion, and the energy conversion module has the function of storing the recovered energy in the form of electric energy.