Battery management system having active and passive cell balancing circuit being controlled by adoptive PWM control

摘要

The present invention relates to a battery management system. In particular, the present invention relates to a cell balancing circuit, and a control algorithm for the circuit, wherein the cell balancing circuit unit uniformly maintains a voltage of a battery cell in a battery bank such as a battery bank for storing large capacity energy, a battery bank for an electric vehicle, or the like. The cell balancing circuit comprises: a cell balancing circuit unit having active/passive cell balancing; a high-speed DSP controller control unit for controlling the cell balancing circuit unit; and a fuzzy function equation for generating a PWM frequency for controlling the high-speed control unit. The fuzzy function equation may be calculated with a logarithmic function having a cell voltage, a cell voltage, a cell current, a cell temperature, a charge time, a discharge time, a voltage change rate, a current change rate, a state of charge (SOC), and a weighted value of a battery use time.