BMS small controller (MAX32625)

Small controller is fixed as small as BMS controller (MAX32625) corresponds, receive the electric core voltage that wraps about each batteries, charge condition (SOC) , health (the newer information of any stoppage that temperature of core of SOH) , report and batteries include a likelihood to appear. Update every 4 minutes to undertake, because electric core voltage, SOC, SOH and temperature predict,won’t change quickly. If produce any breakdown, between two small controller share bring a foot to be buy tall n, spark on small controller interrupt, read instantly then take BMS small controller, get the information of concerned breakdown. There is special I2C port in small controller, use at communication of as small as BMS controller only, correspond in order to support quickly between two small controller.

LTC2971 (IC of power source management)

Small controller runs bus line through power source constantly (PMBUS) agreement and LTC2971 communication, examination voltage, electric current and temperature are measured result and have without warning and breakdown. When measuring backboard to output voltage parameter, LTC2971 has fast feedback effect, so that small controller adjusts its exemple Cheng. In addition, this parts of an apparatus can adjust the feedback voltage of power source transformer, allow its reduce output tension 1% , ensure discharge outputs voltage to be in adjusting range below working mode thereby inside.

MAX31760 (fan controller)

MAX31760 is in charge of adjusting the fan speed of BBU module. Of pulse width modulation occupy sky comparing to be configured by small controller, in order to carry the rate of I2C adjustment fan. Small controller wraps load current according to temperature and backboard load current or batteries, calculate and adjust wants fan rate

24AA512TT (EEPROM? Data stores)

Board carry EEPROM the exterior memory parts of an apparatus of module of appropriative and whole BBU. Small controller is written through I2C shine store a page, mix type of core of batteries tension level, SOC, SOH, report regularly model a particular year and circuit board the important information such as temperature saves EEPROM in. This data is updated hourly, the user can be in safeguard and visit during trouble removal.

LTC2991 (digital board carries temperature to monitor)

LTC2991 is voltage of a 8 passageways, electric current and temperature sensor. Have the aid of of this parts of an apparatus is placed in ministry of batteries model inter block all sorts of number sensor of significant position, the temperature of module of the batteries that monitor. According to temperature reading, small controller can adjust fan speed, the working temperature that ensures power source board and batteries pile maintains in appropriate level, and from beginning to end under 40 ° C.

Small controller still is in charge of those who process cell charging mode. In the begining, the voltage size of electric core is very small, small controller allows to charge for electric core with the electric current of the biggest 5A. Once electric core is in steady state, small controller can adjust charging current for 2A, right now the voltage of every report core has not achieve 4V. Use the data that comes from BMS small controller to monitor electric core voltage continuously, use modulus converter peripheral to measure voltage of whole batteries layer, small controller can judge all report core to whether already achieved 4V, if achieve 4V, small controller is met will charge mode switch is constant voltage mode. This need is charging current limitation only 0.5A. Small controller will continue to monitor level of tension of whole batteries layer, from BMS at the same time small controller gets data, check all batteries to whether fill report. If pursue,2 are shown.

Graph 2. Constant current and constant voltage charge algorithmic

Sufficient understanding BBU is in power source intercourse how from bide one’s time mode transforms mode of batteries power supply is crucial. Lose with data to prevent any accidents to cut off the power, the small controller of module monitors closely backboard tension level. The acquiesce of LT8228 charges mode setting is controlled to 53V in 49V, but if small controller detects,backboard voltage falls inside 2ms to 48.5V the following, can lead LT8228 way the foot instantly from charge mode switch arrives discharge mode, this kind of mode lasts 4 minutes in order to handle power cut case. The module in these 4 minutes will discharge continuously, in order to ensure power supply is uninterrupted. If the condition of electric core allows and backboard voltage is supplied still did not restore, module will await one minute again, so that electric core is cooling, enter discharge mode again next. After power source restores, BBU answers switch advocate power source, begin to charge for batteries. About the specific specification that how be operated and safeguards BBU, ask referenced figure 3 understanding this process.

Graph 3. Fill the processing operation that discharge mode changes

It is very important to make clear breakdown handle a plan. To avoid generation pressure is mixed get bad result, discover potential problem ahead of schedule and make processing plan is crucial. If need to ensure systematic operation moves smoothly, understand the situation that is about to produce, so having smooth communication with the compositive parts of an apparatus in relevant system also is very necessary. Remember please, mistake and breakdown avoid completely hard, and the key that just should be decision result to means. Accordingly, small controller passes special design, can reduce what OCP appoints breakdown to sign up for occurence rate by accident. The firmware program in small controller carries out algorithmic examination to may spark in order to detect the augural phenomenon of breakdown. Detect after relevant omen, algorithm will carry out examination of test and verify, when happen continuously in the problem only or happening inside the periodicity in set, ability can affirm breakdown. This kind of method is very sensible, can ensure identify and resolve real trouble.

Modbus function code is crucial to communication is being established between the parts of an apparatus of Modbus network. These code define the request that sends between parts of an apparatus or response kind, read for example take or keep data. A few commonner Modbus function code include address of register of status of job of module index, module, module and state of fault.

Modbus jussive processing is controlled completely by small controller. Small controller can think for OCP standard command of necessary all and basic Modbus provides support. These commands have authority to change the setting of module, or provide level of tension of core of concerned batteries SOC, moving state, report, charge and the important information of discharge electric current and other parameter. After message of small controller test and verify, can make according to received order answer.

Small controller uses ADM2561 and ADM30611 to send and receive implement, through UART agreement processing comes from the data of all sorts of peripheral, transmit its frame small controller, if pursue,4 are shown. Use segregation model send and receive implement the advantage depends on, it does not suffer the effect that systematic level electromagnetism disturbs, the electromagnetism compatibility that and accord with OCP makes (EMC) standard. In addition, the frame communication to PC is finished through ADM2561, ADM2561 joins through DB9(D-Subminiature) connector and RJ45 Internet port lead plane PC.

Graph 4. Module corresponds to frame and frame corresponds to PC block diagram

Controller framework must want to satisfy dovish and reliable, efficient and the demand with strong adaptability, should have the input of specific definition and output at the same time, can handle Cheng of complex and algorithmic exemple. This framework should be modular, so that support,update without seamed algorithm. In addition still answer inside buy has safe mechanism, in order to be on guard systematic breakdown or accident, can handle accident easily. As a whole, the controller framework of high quality should be offerred reliable and efficient systematic control, can reduce the probability that mistake or breakdown produce at the same time.

(Origin: Yadenuo semiconductor)