A lithium battery management system for fast charging of drones

Abstract

The invention discloses a lithium battery management system for rapid charging of an unmanned aerial vehicle. The balanced simulation includes a drive control unit and a bidirectional DC / DC isolation unit; the analog front end is connected to the main controller, and is used to collect state information of each lithium battery and send it to the main controller to judge whether it is balanced; The balance control unit is connected with the main controller, and is used to receive the balance instruction of the main controller, and control the drive control unit corresponding to the lithium battery, the drive control unit drives the bidirectional DC / DC isolation unit, adjusts the balance current and voltage, and realizes A single lithium battery with high voltage is boosted and discharged to a lithium battery pack or a lithium battery pack is discharged to a single lithium battery. The management system of the present invention has the advantages of being able to equalize multiple lithium batteries at the same time, large equalizing current, fast equalizing speed, simple structure, and convenient control.

Description

technical field [0001] The invention mainly relates to the technical field of unmanned aerial vehicles, in particular to a lithium battery management system for rapid charging of unmanned aerial vehicles. Background technique [0002] For the application of fast charging of drones, the charging current of lithium batteries is very large. When there is a small difference in the internal resistance of the cells, it is easy to cause imbalance between the cells, so it is necessary to adopt balanced charging measures. At present, most of the mature lithium battery management products on the market are passive equalization, but passive equalization is an energy-dissipative equalization method. The acquisition is limited. In order to maximize the use of the acquired energy, an active equalization method should be adopted. At present, the active equalization method mostly uses a converter plus a switch matrix. For example, during the charging process, when the voltage of a cell is h...

AI Technical Summary

Problems solved by technology

At present, most of the mature lithium battery management products on the market are passive equalization, but passive equalization is an energy-dissipative equalization method. The acquisition is limited. In order to maximize the use of the acquired energy, an active equalization method should be adopted. At present, the active equalization method mostly uses a converter plus a switch matrix. For example, during the charging process, when the voltage of a cell is higher than the active equalization upper limit voltage At this time, a part of the charging current of the cell is shunted out and converted by a DC / DC boost circuit to charge the cell with the lowest voltage, so as to realize the energy transmission from the highest voltage cell to the lowest voltage cell, so that The entire battery pack can be charged with more electricity; during the discharge process, when the voltage of a cell is lower than the lower limit voltage of the active balance, the energy of the entire battery pack is transformed and connected in parallel to the lowest voltage through the DC / DC step-down circuit. On the battery cell, this can share part of the discharge current of the battery cell to slow down the voltage drop rate of the battery cell, so that the entire battery pack can release more power; this equalization method can only balance one single battery at a time, charge and discharge During the process, the energy can only flow in one direction, and the discharge and charge can not be balanced. The boost and step-down circuits are physically separated, which brings a certain complexity to the control; and it is not possible to balance several single cells at the same time, and balance all The battery takes a long time, which is not conducive to the application on drones

Images