Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (12): 3883-3894.doi: 10.19799/j.cnki.2095-4239.2022.0158

• Energy Storage System and Engineering • Previous Articles     Next Articles

Design of regenerative braking and power quality harnessed synthetically system in traction substation based on flywheel energy storage

Yanji LI1(), Ying CHEN2, Yiyang LI3   

  1. 1.Tangshan Section of China Railway Beijing Bureau Group Co. , Ltd. , Tangshan 064000, Hebei, China
    2.Hebei Dunshi Magnetic Energy Technology Co. , Ltd.
    3.Shijiazhuang Engineering Vocational College, Shijiazhuang 050000, Hebei, China
  • Received:2022-03-28 Revised:2022-09-13 Online:2022-12-05 Published:2022-12-29
  • Contact: Yanji LI E-mail:hdliyanji@ aliyun.com

Abstract:

The electrified railway is a large industrial user facility with distinctive characteristics. Here, the traction load fluctuates sharply, the negative sequence current is large, and the regenerative braking energy feeds back to the catenary. Hence, negative sequence current will increase the temperature of local metal parts, even leading to transformer burning, shortening the service life of electrical equipment, accelerating the frequency of equipment part replacement, and increasing the cost of equipment maintenance. Furthermore, regenerative braking energy feedback to the catenary will aggravate the load imbalance between the two power supply arms and make the impact of negative sequence currents more serious. However, the traction power supply system cannot use the energy feedback to the catenary. Therefore, the regenerative braking and power quality, which harnessed a synthetic system in traction substations based on flywheel energy storage, was studied. Transformers were first installed on two power supply arms, after which the flywheel energy storage device was connected with feeders through converters and transformers in the whole electrical circuit. Consequently, the system output AC27.5 kV transformed DC1600 V on the feeder to the flywheel energy storage device, causing the flywheel energy storage system to effectively reduce the basic tariff in dual tariff systems. As an energy storage body, the flywheel energy storage device also had the dual functions of storing and releasing electric energy, thereby effectively absorbing and reusing the regenerative electric energy generated during the braking of locomotives and reduction of power rates. In addition, the flywheel energy storage system solved the power quality problem in electrified railways' negative sequences. Thus, compared with the traditional power quality management method, it could produce economic benefits and solve the problem of no economic power quality management.

Key words: traction substation, regenerative braking, negative sequence current, flywheel energy storage

CLC Number: