Method and system for online detection and correction of SOC of lithium titanate battery of variable pitch backup power supply

Abstract

The invention relates to a variable pitch back-up power supply lithium titanate battery SOC online detection and correction method and system, and the method comprises the following steps: 1, carrying out a charging test, charging a lithium titanate battery in a variable pitch system back-up power supply according to a set charging parameter, sampling in the charging process, exporting sampling data, and calculating the obtained SOC at each sampling moment; 2, drawing an SOC-V scatter diagram of the SOC of the lithium titanate battery with respect to the voltage of the lithium titanate battery, and performing fitting to obtain a fitting function E; 3, checking the fitting function E in the process of charging or discharging the lithium titanate battery by using a variable pitch system, and if the calculation precision of the fitting function E does not accord with the set precision, correcting the fitting function E; and step 4, using an SOC-V curve, namely a fitting function E, detecting the residual energy of the lithium titanate battery on line according to the voltage of the lithium titanate battery, preventing the situation that the paddle cannot return to a safe position due to insufficient energy, and performing health monitoring and fault judgment on the lithium titanate battery through the SOC-V curve.

Description

technical field [0001] The invention belongs to the technical field of pitch control systems for wind power generating sets, and more specifically relates to an SOC online detection and correction method using a lithium titanate battery as a backup power source for a pitch system. Background technique [0002] With the continuous development of wind power technology, large-capacity models are the development trend of the wind power industry. Among them, 2MW and 3MW models have become the mainstream models of onshore wind farms, and 6-8MW models have been applied in offshore wind farms. At present, many wind turbine manufacturers are developing 10MW and above models. In the near future, China's wind power market will enter the era of 10MW. [0003] With the continuous improvement of the capacity of wind turbines, the length of blades gradually increases. For the pitch system of wind turbines, the operating load will become larger and larger. The more energy provided by the ...

AI Technical Summary

Problems solved by technology

[0005] Due to the different working principles of lithium titanate batteries and supercapacitors, it is impossible to judge lithium titanate batteries simply by using the health assessment method of supercapacitors.

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