CELL BALANCING CIRCUIT BASED ON ENERGY TRANSFER VIA INDUCTOR

• Main Authors: YOSHINO RYOZO, OGINO NAOAKI, MATSUO YUZO, MORI HIROYUKI
• Format: Patent
• Language: English
• Published: 17.01.2013
• Subjects: BASIC ELECTRIC ELEMENTS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTINGELECTRIC POWER; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER; ELECTRICITY; GENERATION; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; SYSTEMS FOR STORING ELECTRIC ENERGY

PROBLEM TO BE SOLVED: To equalize cell voltages in a battery module in a short time without wasting energy stored in cells by transferring energy between arbitrary cells.SOLUTION: A cell balancing circuit includes: a voltage detection section 2 for detecting each cell voltage of a battery module 1; an inductor L for energy transfer; a single cell connection switch group 4 capable of connecting the inductor between positive and negative electrodes of a selected single cell of the battery module; and a switch control section 3 for controlling the single cell connection switch group so as to connect the inductor between positive and negative electrodes of a predetermined single cell on the basis of each cell voltage detected by the voltage detection section. The switch control section controls the single cell connection switch group so as to make a charging path for a flow of current from a high voltage cell to the inductor, break the charging path in a predetermined time, make a discharging path for a flow of current from the inductor to a low voltage cell in parallel to breaking the charging path, and then break the discharging path in the predetermined time.