Bus voltage modulation method for series dynamic reconfiguration battery system

A bus voltage modulation method for a series dynamic reconfiguration battery system, comprising the following steps:

• S1:
• starting battery module selection, wherein all battery modules are numbered as i based on bus requirements, a voltage value of each battery module is collected, all battery modules are arranged in a descending order by magnitudes of voltage values, and a battery module corresponding to the highest voltage value is numbered as 0, sequentially numbered as i=0, i=1, i=2 . . . by the magnitudes of voltage values;
• S2:
• selecting the battery module corresponding to the highest voltage value, i.e., i=0;
• S3:
• determining whether a serial number i of the battery module selected is less than a total number N of series battery modules, and if a determination result is YES, accumulating voltage values corresponding to the battery modules selected, and determining whether a voltage accumulation value Σvi of the battery modules is within a preset range;
• S4:
• performing an i++ operation according to the voltage accumulation value Σvi of the battery modules, and repeating S2-S3 until an output bus voltage meets requirements for the preset range,
• wherein in S3, determining steps for determining whether the voltage accumulation value Σvi of the battery modules is within the preset range specifically comprise:
• S31:
• comparing the voltage accumulation value Σvi of the battery modules with a bus voltage modulation output lower limit value V1, determining whether the voltage accumulation value Σvi of the battery modules is smaller than the bus voltage modulation output lower limit value V1, and skipping to S32 if a determination result is YES;
• otherwise, skipping to S33;
• S32:
• based on a result determining to be YES in S31, placing the battery module selected at this time into a switch-on group, accumulating a voltage value corresponding to the battery module into the voltage accumulation value, then performing an i++ operation, and repeating steps S2-S3;
• S33:
• comparing the voltage accumulation value Σvi of the battery modules with a bus voltage modulation output upper limit value V2, determining whether the voltage accumulation value Σvi of the battery modules is greater than the bus voltage modulation output upper limit value V2, and skipping to S34 if a determination result is YES;
• if the determination result is NO, issuing commands by the switch-on group and a switch bypass group, completing a serial reconfiguration action, and ending the battery module selection;
• S34:
• based on a result determining to be YES in S33, placing the battery module accumulated at this time into the switch bypass group, not accumulating the voltage value corresponding to the battery module selected at this time into the voltage accumulation value, performing an i++ operation, and repeating S2-S3,
• wherein in S3, whether the serial number i of the battery module selected is smaller than the total number N of series battery modules is determined, and if a determination result is NO, skipping to S5;
• S5:
• determining whether selected combinations of all the battery modules are all attempted, if it is determined to be YES, skipping to step S6;
• if it is determined to be NO, shielding one main battery module, and repeating S2-S4, wherein the battery modules comprise main battery modules and dummy battery modules;
• and
• S6:
• keeping a last selection result, or disconnecting network cards of all battery modules, and starting a mechanism for actively generating a voltage difference between the battery modules.