Double-fed aerogenerator excitation system based on the hybrid stored energy of super capacitor and storage battery

Abstract

The invention belongs to the technical field of the power quality control of wind power generation, in particular a double-fed aerogenerator excitation system based on the hybrid stored energy of a super capacitor and a storage battery. The system is characterized by comprising a rotor side converter 3, a net side converter 4, a chopper A5, a chopper B7, a super capacitor 6, a storage battery 8, a bilateral switch as well as a limiting resistor Rl and a direct current side capacitor C, wherein a hybrid stored energy device comprising the chopper A5, the chopper B7, the supper capacitor 6 and the storage battery 8 is connected to both ends of the direct current capacitor in parallel; the rotor side converter 3 is responsible for providing excitation power to an aerogenerator; the net side converter 4 is responsible for transmitting power exchanging with the output end of the rotor side of the aerogenerator, and exactly controlling the charge and discharge power of the storage battery and the super capacitor by controlling the chopper A5 and the chopper B7 so as to compensate external power fluctuation. The invention has the advantages that the aerogenerator generates stable electrical energy under the condition of the frequent fluctuation of the aerogenerator, the safe stability of large-scale synchronization running of a wind farm is improved, and the excitation system can also be widely used in ocean power generation such as wave-actuated power generation and tidal power generation.

Description

technical field [0001] The invention belongs to the technical field of power quality control for wind power generation, and relates to a doubly-fed wind power generator excitation system incorporating a hybrid energy storage device, in particular to the application of an excitation converter based on a battery and supercapacitor hybrid energy storage system in a wind power system . Background technique [0002] The development and utilization of renewable energy has opened up a new way to solve global energy and environmental problems, and has important strategic significance for improving the energy structure and ensuring the sustainable development of the national economy. Wind energy is currently the renewable energy with the greatest potential for large-scale development and utilization, and wind power generation is considered to be the most obvious choice to realize the sustainable development strategy of energy and electric power in our country. [0003] Wind power gr...

AI Technical Summary

Problems solved by technology

However, this type of storage battery also has some disadvantages: First, because the wind speed fluctuation is random, the fluctuation of wind power power also has the characteristics of discontinuity and unpredictability. In order to stabilize the fluctuation, the battery needs to perform frequent charging and discharging cycles. This small cycle of charging and discharging will seriously affect the capacity of the battery, greatly reduce the service life of the battery, and increase the operating cost of the wind farm

The energy storage density of supercapacitors is low. For the long-term power fluctuations that often occur in wind farms, only using supercapacitors for power stabilization will greatly increase the requirements for supercapacitor capacity, making the equipment too bulky and expensive. also high

Images