Method for calculating SOC of new energy automobile battery management system

Abstract

The invention relates to a method for calculating SOC of a new energy automobile battery management system. The method for calculating SOC of the new energy automobile battery management system comprises the following steps: judging a battery state under the management of the battery management system, calculating a corresponding real-time SOC value SOCraw based on the battery state, and performing temperature compensation calculation on the SOCraw to obtain final SOCfin values under different battery states, wherein the battery states are divided into a new battery primary use state and a single battery abnormal state. By using the method for calculating SOC of the new energy automobile battery management system, an initial SOC value of a new battery can be accurately calculated, accuracyof the SOC of a single battery in an abnormal state can be ensured, the influence of the temperature on the battery is considered, the accuracy of the SOC is further improved, and a SOC gain is adjusted at different temperatures so that a control process is optimized, and a service life of the battery is prolonged.

Description

technical field [0001] The invention belongs to the technical field of battery management systems, and in particular relates to a method for calculating SOC by a battery management system of a new energy vehicle. Background technique [0002] With the advancement of battery energy storage system technology, the specific energy of battery energy storage has increased rapidly, and the unit cost has gradually decreased. Coupled with the characteristics of fast response and convenient setting of the battery energy storage system itself, the application of the battery energy storage system has become more and more extensive. In the connection of new energy (such as wind power generation, solar photovoltaic power generation) as an energy buffer device, smooth new energy and increase the penetration rate of new energy; as a braking energy recovery device in automobiles, it also serves as a special working condition (such as Start, accelerate) auxiliary power energy supply device (...

AI Technical Summary

Problems solved by technology

[0004] If there is no accurate SOC, what will happen: overcharge / overdischarge, resulting in shortened battery life, sagging, etc.; the uniformity of the balance is not ideal, reducing the output power, and the power performance is reduced; in order to avoid slack, set the Multi-redundant power reduces the overall energy output, so the accurate calculation of SOC is of great significance, and its algorithm is also one of the core competitiveness of related companies

[0005] In the BMS control of new energy vehicles in existing products, the SOC calculation is usually based on the ampere-hour integral method, but when the battery pack is newly used, the SOC value cannot be accurately calculated, and it is often necessary to charge it once before it can be used. The calculation of SOC is more accurate, and in the process of use, if there is an abnormality (open circuit, cable falling, etc.) of a single battery, the battery management cannot correctly calculate the SOC value. These are the SOC in the traditional new energy vehicle battery management system. Computing Disadvantages

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