| 摘要 |
An active charge equilibrium system for lithium battery pack consists a lithium battery pack composed of connecting multiple cells in series, including a multiplex module, control module and multiple equilibrium control module, which each segment of the cells are connected to the multiplex module in sequence, a voltage signal is converted into a digital signal via the control module to compare the voltages of the cells and select the cell with lower voltage. Further, the control module enables the equilibrium control module corresponding to the cell with the lower voltage to work. A pulse width modulator adjusts the output pulse width according to output current and voltage signal from a signal feedback module for controlling current and voltage to charge the cell. As the voltage of the cell reaches a constant current first and a constant voltage second, the control module turns off said equilibrium control module. |
| 主权项 |
1. An active charge equilibrium system for lithium battery pack, connecting electrically to at least one lithium battery pack, said lithium battery pack being composed of multiple battery cells in series, while said active charge equilibrium system for lithium battery pack including:
a multiplex module, including a multiplexer and a differential amplifier, positive and negative electrodes of said cells being connected electrically with said multiplexer sequentially, an output end of said multiplexer being connected to an input of said differential amplifier; a control module, including a digital to analog converter and a microcontroller, an input of said digital to analog converter being connected to the output of said differential amplifier, an input of said microcontroller being connected to the output of said digital to analog converter, and said microcontroller being capable of outputting a control signal; multiple equilibrium control modules, connecting electrically to the cells correspondingly, said equilibrium control module including a transformer, a NMOS transistor, a signal feedback unit and a pulse width modulator, said transformer having a primary side coil and a secondary side coil, said primary side coil of said transformer and said NMOS transistor being connected with said lithium battery pack in series sequentially to form a first circuit, said secondary side coil of said transformer being connecting with each of the corresponding cells in series to form a second circuit, one end of said signal feedback unit being connected between said secondary side coil of said transformer and the corresponding cell, and the other fend thereof is connected to said pulse width modulator to receive the output signal of said secondary side coil of said transformer and deliver to said pulse width modulator, said pulse width modulator being further connected with its NMOS transistor, and being connected with the microcontroller of said control module, such that the control signal of said microcontroller being capable of controlling conduction of said NMOS transistor through said pulse width modulator. |
