An adaptive stable observer for on board auxiliary inverters with online current identification strategy

• Published in: Journal of Central South University Vol. 24; no. 4; pp. 819 - 828
• Main Authors: Li, Wei, Liu, You-mei, Chen, Te-fang, Deng, Jiang-ming
• Format: Journal Article
• Language: English
• Published: Changsha Central South University 01-04-2017; Springer Nature B.V
• Subjects: Direct current; Engineering; Error analysis; High speed rail; Inverters; Magnetic levitation railways; Magnetic levitation vehicles; Metallic Materials; Urban rail; adaptive observer; online identification; parameter variation; auxiliary inverter; Lyapunov function
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-017-3484-y

An adaptive stable observer with output current online identification strategy for the auxiliary inverters applied in advanced electric trains, such as high speed railway, urban rail, subway and maglev trains, is proposed. The designed observer is used to estimate the state variables, i.e. controllable duty ratio and current components in d-q-o rotary reference frame. The convergence of the observer estimation error is analyzed with consideration of uncertain level variation of input voltage at direct current (DC) side and sufficient conditions are given to prove its practical stability. Experimental results are shown to confirm the effectiveness of the proposed observer.