A method for evaluating the health status of wind power pitch supercapacitor backup power

Abstract

The invention discloses a method for evaluating the health state of a wind power variable pitch super capacitor backup power supply, comprising the following five steps: (1) data acquisition and preprocessing, (2) construction of a mixed attribute matrix, (3) evaluation threshold determination, (4) Calculation of the hybrid weighted Euclidean distance of the supercapacitor to be evaluated for the backup power supply, (5) Calculation and evaluation of the health state index of the supercapacitor of the backup power supply. The beneficial effects of the present invention are: using the voltage, current, temperature and external characteristic parameter data of the charging and discharging capacity in the charging and discharging process of the super capacitor, and adopting the data clustering mining method to comprehensively evaluate the health status of the wind power variable pitch super capacitor backup power supply It effectively avoids the problems of reasonable and accurate equivalent circuit modeling and complex parameter identification of the existing evaluation methods, and has the characteristics of simple evaluation process, fast speed and high precision.

Description

Technical field [0001] The present invention belongs to the supercapacitor health state evaluation method, in particular a wind power converter supercapacitor backup power state evaluation method. Background [0002] Wind power has become an important direction for the development of renewable energy in the world, playing an important role in energy and environmental protection. The pitch system is an important part of the wind turbine, usually in the case of sudden grid voltage drops, extreme bad weather power loss, the backup power supply is used for emergency shunting to ensure the safe operation of the wind turbine. The supercapacitor has the advantages of high power density, fast charging and discharging speed, long cycle life, green environmental protection for scrap treatment, and can withstand instantaneous high-current charging and discharging, and gradually replaces traditional batteries such as lead-acid batteries as the backup power source of the wind turbine pitch sy...

AI Technical Summary

Problems solved by technology

[0003] The failure of supercapacitors is usually caused by aging. The aging causes debonding and microcracks of carbon electrode particles from the physical and chemical properties, which affects the stability of the electrolyte, which will cause the internal resistance of the supercapacitor to increase and the capacitance to decrease. The health status continues to deteriorate, which in turn affects the performance of the supercapacitor power supply

At present, the existing supercapacitor health evaluation methods are mainly based on the supercapacitor equivalent circuit model, using parameter data such as voltage, current, temperature, etc. and use these parameters as indicators to evaluate the health status of the super capacitor. The rationality of the equivalent circuit modeling of the super capacitor directly affects the estimation accuracy, which in turn affects the evaluation results of its health status. Based on the capacitance principle, a reasonable and accurate supercapacitor equivalent circuit is established, so these methods have certain limitations.

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