Yang Zhongping

A study of electric double layer capacitors improving electric network voltage fluctuation for urban railway transit

This paper presents a state-averaged model and an effective control method of a regenerative power storage system to save energy and improve electric network voltage fluctuation in urban railway transit. The regenerative power is stored and then provided to a traction motor by the storage system that consists of an electric double layer capacitors (EDLC) and bi-directional DC/DC converter. We have designed a new control system using voltage and current control mode to achieve the stability and the quick response. The utility of the proposed method is examined through computer. Finally, we constructed an experiment equipment which contains diode bridge rectifiers, a bi-directional DC/DC converter, EDLC and PWM inverter.

Power distribution control strategy of on-board supercapacitor energy storage system of railway vehicle

Supercapacitor, with high power density and long cycle life, has unique advantages and development prospects in avoiding regeneration failure, improving the braking force in high-speed range and realizing catenary-free operation in urban railway. First, the characteristic curves of the vehicle and characteristics of supercapacitors are studied. Based on matching their characteristics, a power distribution control strategy for on-board supercapacitor energy storage system is proposed. A simulation model and a 3kW experimental platform are set up, in order to simulate single vehicle and single substation. Both of the simulation results and experimental results have verified the feasibility of the control strategy.

Pure electric brake of linear induction motor in the linear metro

Pure electric brake of LIM (Linear Induction Motor) for Linear Metro is proposed in this paper. First, a dynamic mathematical model of LIM is derived based on analyzing the end effect. Then a field orientation control scheme is developed through the analysis of the difference between linear motor and rotary motor control. On this basis, giving speed instruction in traction condition and giving force instruction in brake condition to achieve pure electric brake in LIM, which is composed of regenerative brake and reversal brake. This paper also discusses the switching mode from regenerative brake to reversal brake, and removal time of reversal brake. The effectiveness of the proposed control strategy is verified through simulation and experimental results.