Two-stage equalizing charging system and application thereof

Abstract

The invention discloses a two-stage equalizing charging system and an application thereof. A first-stage equalizing module adopts a multi-winding transformer magnetic model, and a second-stage equalizing module adopts an improved multi-primary-winding direct current (DC)-DC equalizing model. The application of the second-stage equalizing charging system on a hybrid electric vehicle storage battery pack is characterized in that the hybrid electric vehicle storage battery pack is subjected to multi-stage grouping, and then the battery pack is controlled step by step. The two-stage equalizing charging system is high in equalizing speed, good in voltage consistency and applicable to the occasions where a vehicle-mounted battery of a hybrid vehicle is large, has the advantages of being good in equalizing effect, high in charging efficiency, good in system expandability and the like, and has good application prospects in the fields of energy saving and new energy automobiles.

Description

technical field [0001] The invention belongs to the field of energy-saving and new-energy vehicles, and relates to a two-stage balanced charging system and its application. Background technique [0002] With the tension of energy issues, in the long run, hybrid vehicles are the future development trend, and hybrid vehicles are considered to be the most promising models at present, so hybrid vehicles will be the mainstream of new energy vehicles in the future. Since battery energy has lower energy density and poor battery life than gasoline energy, it is particularly important to cycle charge the battery. The unbalanced phenomenon in the charging process will cause some batteries to be overcharged. And some batteries are in a state of undercharging, which has a great impact on the life of the battery. [0003] Therefore, in order to reduce the battery unbalance of the battery pack connected in series, it is necessary to control the balance of the battery pack during the char...

AI Technical Summary

Problems solved by technology

Among various equalization schemes, the equalization control technology can be divided into two types: dissipative equalization diffusion and non-dissipative equalization: the dissipative equalization method is simple to control, but there will be energy loss; the discharge two-way equalization in the non-dissipative equalization The control circuit of the method is too complicated to realize

The equalization scheme based on the primary side winding is used. This method has high equalization efficiency and low cost, and can be used for battery packs with many batteries connected in series. However, it is difficult to achieve the same number of turns in the equalization process. Therefore, there are inconsistencies in the equilibrium, so there are still some difficulties in practical application.

The equalization efficiency of the DC converter is high, and the consistency is high. The only problem is that when there are many batteries, the cost is too high.

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