A Control Strategy of Hybrid Energy Storage Based on Three-level DC/DC Converter
Aiming at the problems of high voltage level,large energy flow and frequent starting and bra-king in urban rail transit,a control strategy of hybrid energy storage system based on three-level DC/DC converter is proposed.Energy type Energy Storage Device(EESD)expands capacity in parallel to meet high energy demand and play a role in maintaining DC traction bus voltage stability.Power type Energy Storage Device(PESD)Satisfy the high power demand under start-up braking conditions and improve the dynamic response characteristics.The low pass filter is used to realize the command power distribution of EESD and PESD,the droop control is used to realize the power sharing of multiple groups of EESDs with different line impedances,and the voltage compensation control is used to reduce the control error of the DC traction bus voltage.Finally,simulation experiments are carried out on the Matlab/Simulink simula-tion platform under the conditions of charging and discharging,starting and braking,light load and heavy load,etc.,to verify the feasibility and effectiveness of the scheme.
three-level DC/DChybrid energy storagepower distributiondroop controlvoltage compen-sation
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维普
