Design method of 2MWH energy storage system based on colloid lead-acid battery

　　Author ：Iflowpower – Portable Power Station Supplier

1 Requirements Analysis Tube Colloidal Lead Acid Battery Equipment Supported by tubular colloidal lead-acid batteries, BMS, affiliate equipment, spare parts, special tools and installation accessories, etc. According to the characteristics of the project, according to the designation requirements, the comprehensive lead-acid battery characteristics, the energy storage system is subjected to the following designs: 336 2V1000AH tubular colloid lead-acid battery is connected in series, voltage 672V, battery string capacity 672KWH. Each 3 battery stacks are connected in parallel to a 500KWH energy storage two-way transformer.

The total capacity of the three battery stacks can reach 2MWH. Three battery stacks in this method are one reservoir unit. Each unit configures a BMS battery management system to monitor each human cell voltage, internal resistance, and temperature.

Current. Factory-containing smoking probe, fire extinguisher, environmental control system, hydrogen supply system, video surveillance system, temperature and humidity monitoring and other equipment to ensure a safe and stable working environment of lead-acid batteries. 2 The battery pack is a group method above the group method, which fully considers the problem of a circular flow in multiple groups and losses, and it is also fully considered that the main carrier flow of the system is fully considered, and the copper row is used in the battery cluster.

System running demand, use copper lines in the form of copper lines in the cross-clustered connection, 300A. System design multi-level switch protection, convenient wiring and system control. 2.

1 Battery group Strings internal and inter-group connection method 2.2 System topology graph copper row joint, overall stabilizing body, may reduce the loose phenomenon caused by vibration and other reasons during subsequent operation. In addition, full sheathed copper row and insulated terminal cap protection are used to improve the safety insulation level of the battery pack.

The following figure shows the overall contrast method of the energy storage system, and the internal battery pack is connected. Battery group to DC power distribution cabinet is connected by cable, the cable enters the DC power distribution cabinet through the bottom cable. The weak electric line of the BMS system is separated from the DC line, reducing the drying, the weak electric lines pass the iron wire tube to DC power distribution cabinets or with shielded cable.

DC power distribution cabinet to PCS adopts cable access to PCS DC side input circuit breakers via cable trenus, BMMS communication cable is introduced into PCS and energy storage system in-site monitoring system via cable trenus. 3 Battery Management System (BMS) 3.1BMS System Overall Array This BMS system is a battery management system designed according to the characteristics of large-scale storage battery arrays.

This system uses lead-acid batteries for energy storage battery arrays for energy storage units for Monitoring, assessing and protecting battery operating states, including: monitoring and delivering operational status information of lead-acid batteries, battery packs, and battery system units, such as battery voltage, current, temperature, internal resistance, etc. Battery's charge state SOC, life health status SOH and battery accumulated processing energy, etc .; protect battery safety, etc.

This BMS system consists of ESMU, ESGU and BMM: ENERGYSTORAGESYSTEMAGEMENTUNIT ENERGYSTORAGESYSTEMANAGEMENTUNIT EnergySystem management unit, the management unit performs numerical calculation, performance analysis, alarm processing, and record storage for BMM uploaded battery real-time data; each ESMU management two ESGU module. ESGU (EnergyStorageBatteryGroupTrolunit) Battery Group Control Unit, ESGU is important to collect, collect the total voltage and current of the entire set of batteries, anomalous to the battery pack; each ESGU management 14 cluster battery. BatteryMonitoringModule battery pack monitoring module, the unit set battery operation information monitoring acquisition, automatic charging, discharging equalization management, online internal resistance test, fault diagnosis, etc.

Each module can manage a cluster (24) single battery. Each set of battery cells corresponds to 14 clustered batteries, 14 BMM. The BMS system has the following characteristics: comprehensive battery information management, online SOC diagnosis, lossless active equalization charging management, system protection function, heat management function, self-fault diagnosis and fault tolerance technology, professional load linkage control and optimization, flexible modular design.

3.2BMS system Important equipment introduction Battery monitoring module BMM3.1 This unit set battery operation information monitoring acquisition, charging equalization management, fault diagnosis and other functions.

The design is compact, highly integrated, each unit is good, reliability, high security, high security. Each module can monitor and maintain 24 string cells, connect multiple-channel temperature sensors, and the energy storage battery management module and the RS485 or CAN connection between the energy storage system management unit can be connected.øAutomatically detect each battery voltage, battery pack voltage, charge and discharge current, and temperature, etc.

øReal-time alarm function, realize over-limit alarms for voltage, temperature and current;øOn-site alarm, dry node output closed, can realize remote computer alarms and display alarm content;øOnline automatic regular (cycle can be set) testing the internal resistance of the battery;øWith RS485 / or CAN communication interface, access to monitoring systems or field acquisition units, realizing data and alarm information, achieving the purpose of remote monitoring battery pack;øEasy to use modular design, installation, use, and maintenance, and the module is isolated from each other, high reliability;øThe product has a battery pack online equilibrium maintenance function, which can charge the battery pack voltage consistency by charging the monomer battery online, and reaches the purpose of delaying the failure of the battery. Industry Battery Monitoring Module BMM3.1 Introduction Battery Group Control Module ESGUESGU is important to collect, collect the total voltage and current of the entire set of batteries, anomalizing the abnormality of the battery pack; The requirements for processing rules are protected to ensure the safety, stable operation of the battery system, when the battery is seriously overpriced, undervoltage, overcurrent (short circuit), leakage (insulation), etc.

, the energy storage system management unit The command to the unit, control the opening of the entire set of batteries, preventing the battery from being overturned, overproduced and overcurrent.øThe specific function is equipped with power-on self-test function. It is important to include all sensors, system status, etc .

; with battery-end voltage, current, temperature and other detection function; with battery positive and negative electrode to the case of insulation detection function; with management main contactor Control and main contactor feedback signal detection function; abnormal alarms and hard touch protection control functions; with CAN / RS485 bus communication function. Battery Group Control Module ESGU Introduction System Management Unit ESMU Value calculation, performance analysis, alarm processing, and record storage for BMM3.1 uploaded by BMM3.

1, in addition, one-on-one implementation with PCS host, energy storage scheduling monitoring System, etc., linkage control, according to output power requirements and SOC of each group of batteries to ensure that the total running time of all battery packs tends to be consistent.øSpecific function a.

Monitor display data 1) Monitor display cell voltage data. 2) Monitor display current data. 3) Monitor the display temperature.

Temperature includes: ambient temperature, data of BMM3.1. b.

Alarm function 1) Communication connection alarm. 2) Temperature is too high or too low alarm. 3) The monomer voltage is too high and too low alarm.

4) The terminal voltage is too high or too low alarm. 5) BMM3.1 error alarm.

c. Protect 1) The monomer voltage is too low or too high. 2) Temperature is too low or high protection.

3) The terminal voltage is too high or low protection. d. Parameter Setting 1) Settings 2) Network Communication Parameter Settings 3) Interface Protocol Parameter Settings 4) ESGU Parameter Set Index System Management Unit Real Map 3.

3BMS System Protection Mode Storage BMS and PCS and There are data communication in the background, communication mode and PCS is an Ethernet or RS485, and the background monitoring is an Ethernet, and the communication protocol adopted is Modbus or IEC61850 (optional) to ensure communication abnormalities in BMS and PCS. At the time, BMS, battery, background can work properly. Battery Management BMS and background communication adopts standard Modbus protocol or IEC61850 (optional), high performance, high reliability, real-time communication capabilities, has a variety of error detection, guaranteeing the accurate data volume upload and instructions issued Sex and timely.

BMS is connected in two ways of Ethernet (or RS485) and two hard points to ensure that timely stop in time when the battery pack is seriously fault. 3.4BMS system communication method The entire energy storage system has a capacity of 28mWh; the system consists of 14 PCS battery cells, and the system uses a lead-acid monomer battery of 2V / 1000AH.

The energy storage system uses a battery pack of 336 2V / 1000AH constituting a set of batteries, and the three sets of batteries constitute a battery unit, each battery cell capacity is 2mWh, namely 336 sections.×2V×1000AH×3 = 2.016mWh; Each minimum module supports 24-knitted cells, 336 batteries to 336/24 = 14 modules; the entire energy storage system 14 battery cells accumulated a total capacity of 2.

016MWH×14 = 28.224MWH; Common efficiency of the energy storage inverter is 92% to 95%, so the actual capacity of the entire energy storage is 28.224MWH.

×0.92 = 25.97mWh, the architecture is as follows: The system is used in three sets of batteries in the DC side, and the functional schematic of the battery cluster access PCS is as follows: The total capacity of the energy storage system is 336.

×2V×1000AH×3 groups×14PCS×92% = 25.97mWh, the system uses lead-acid batteries as the energy storage unit, using a battery management system (BMS) with active lossless equalization and capacity diagnosis, using the currently mature two-way inverter (PCS), the entire system The background is unified, the battery is installed with battery. 4 For lead-acid battery storage energy buildings require a lot of requirements for large energy storage plants, it is necessary to ensure that lead-acid batteries work in rated operating temperatures, extend storage unit work life, but also to configure security systems to ensure system security Operation, from the following aspects to design a large computer room; temperature control system ensures that the overall temperature uniformity of the stereotactic space in the plant is 5 degrees to ensure the uninterruption of the overall discharge of lead-acid battery monomers.

To design a thermal management system for stereoscopic space for the entire plant for this purpose. To configure a flap and a new wind system. The hydrogen hydrogen system causes the hydrogenation reaction due to the sealing valve-controlled lead-acid battery in the case of overcharge, resulting in an increase in internal pressure, thereby equipped with hydrogen detection and hydrogen production system.

In view of the fact that the plane space in the entire room is relatively large, it is difficult to achieve the hydrogen requirements if the hydrogen supply is set on the side of the plant side, and the uppermost layer of the entire room is usually in the entire room. Hydrogen detection excformer and special hydrogen source. This system automatically runs, you can achieve a pressing hydrogen in time and control it by hydrogen concentration, etc.

The temperature should be controlled at 5 ~ 35 degrees, the humidity is 40% ~ 80%, and the wiring is recommended to use a hanging wireclip wiring to facilitate maintenance. According to the "Construction Ground Engineering Construction Quality Acceptance Specification" GB50209 specified in the flatness of 4mm / 2000mm, the ground floor is also required to meet this flatness requirements. Take 2 tons per square meter.

In response to this project, the built-in plant must have an independent power supply system, temperature and humidity system, insulation flame retardant system, fire alarm system, safety escape system, fire protection system, hydrogen production system, etc., etc.