3.3 Battery Diagnosis Fuzzy Expert System used by the rules
We are experts on the battery fault diagnostic rules of the VGP-BPS9A VGP-BPS10 battery, battery diagnostics and maintenance of an analysis of data collected on expert systems. And then verified by experiment to make compromises and many more [2]. With lithium-ion, for example, the rules of the system are:
(1) The discharge voltage drop fast, low voltage, the charging voltage up fast, high voltage, capacity, smaller battery;
(2) put aside for when the voltage drop from the battery terminal fast voltage long-term investment is low, then the self-discharge is too large;
(3) Freeing the administration of the battery voltage drops rapidly, the average voltage and low voltage of 1 volt or two, there are battery cell damage;
(4) The battery open circuit voltage is very low, could not take charge, the battery is damaged or the connection is not normal; Inspiron 630m battery Inspiron 640m battery
(5) The charging voltage of the discharge at high voltage is low, then the only internal resistance of the battery is too high;
(6) The charging voltage is high, the internal battery in open circuit;
(7) Since the beginning of the discharge of the battery, its voltage was slightly lower than other cells, their performance platform for the discharge to the normal battery in May to the charge is insufficient;
(8), the battery in the discharge process, a section of battery temperature greater than any single other battery temperature only 3 ℃ above the battery internal resistance is too great.
3.4 The content of data and creation of historical archives
In this study, lithium iron phosphate, for example, stored in the historical archives of data are:
(1) Battery Plant of data (such as date of manufacture, nominal capacity, the open circuit voltage, etc.); Satellite M55 battery Tecra A3 battery
(2) the total number of hours security;
(3), overload and discharge when the maximum voltage, current, temperature records;
(4) The last 10 cycle charge-discharge charge cycles belonging to the highest voltage of the frequency and voltage discharge cycles belonging to the lowest number of sessions;
(5) Last 10 cycles of temperature data movements within the taxation and pricing efficiency;
(6) The last 10 cycles, when a small current to the load voltage difference;
(7) Since the time interval of discharge;
(8) The last time health diagnosis (SOH) results.
In the system executes the first time in the history file is initialized. The principle is to initialize the exception of certain basic parameters are known, other parts are best. In the further course of the operation, the system automatically and battery-related events recorded in the history files to edit. If the battery replaced a single battery down, in turn, should have just replaced the battery in the historical archives to initialize. The use of historical archives of the total number of hours of security, the total number of cycles of charge-discharge, over charge, over discharge, and charge less than the impact of battery life and health the long-term memory and make use of the cumulative approach, for other performance characteristics of historical data Refresh method is applied on a regular basis. Inspiron 1100 battery Inspiron 1150 battery
Historical Archives of the concrete realization of the program are: the use of long-term memory in the system EEPROM chip to store historical data, while in the system, plus a clock circuit and a pile of historical data provide information in time.
3.5 Failure process of defining and
The system uses four definitions fault alarm, respectively, a failure of the temperature, because high-temperature, single failure at high voltage, 234 non-temperature, pressure failure, the lack of high temperature, single failure in high voltage monomer voltage is too low failure.
When the power system, data acquisition of the battery into the battery loading process and unloading intervals monomer recycling collection cell voltage, temperature and other information. When the failure to record failures and calibration number monomer. When the number of calibration to a single failure of a certain amount of cumulative number of times when the 75UYF G5266 battery performance is called the rule base pairs evaluated at the same time will assess the results recorded in history the file.
4 Experimental results and analysis
In this study, lithium-ion battery packs used in the module to the battery pack for electric vehicles using lithium iron phosphate Pack, autonomous system module consists of 12 single of 30Ah batteries in series. Battery modules are equipped with management module battery data acquisition module via the CAN bus will collect data for transmission. After CAN232 interface converter, using data from the CAN data frame in a PC format, can be identified through the RS232 interface is passed to the host computer to display the human-machine interface .
Figure 4 is a group of battery charge and actual discharge cycles carried out a number of data collected. Because of differences between the monomer battery, 7 single-ended voltage and the other major difference between the monomer, there were two failures and one low pressure alarm voltage fault. 367759-001 F2024A
5 Conclusion
(1) Analysis of battery and change the batteries in the external features of the data link between failures, combined with experience and expert knowledge of the battery, summed up the battery to the common rules of diagnosis failures.
(2) has developed a battery platform data acquisition system, including the underlying hardware, data acquisition, data communications, procedures of the host computer interface for the preparation of human interaction machine. The new data collection procedures and communication between the system battery management more secure, reliable, and not the management system of the battery to control the number of types of conversion and change of PA-16 9T215 batteries.
(3) to build the battery fault diagnosis fuzzy expert system. To find used to describe the external symptoms of battery failure and battery to build a bridge between the fuzzy relationship. At the same time as the experiments continue, continue to refine the diagnostic system of experts for lack of early warning to protect more reliable.
As a relatively small number of the current experiment, such as dynamic characteristics of the battery and the fault could not be verified, the system of fault diagnosis can not be verified. With the continuous deepening of experience, information battery fault will also be gradually accumulated, a rule base and inference engine will also continue to be corrected. F1781A PA1650