Open AccessBoost multi‐level NPC‐fed VS large rated asynchronous pumped storage hydro‐generating unit
Author(s) -
Joseph Anto,
Kim SeokMin,
Sing Lee Sze,
Dominic Arun,
Lee KyoBeum
Publication year - 2019
Publication title -
iet electric power applications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.815
H-Index - 97
eISSN - 1751-8679
pISSN - 1751-8660
DOI - 10.1049/iet-epa.2018.5851
Subject(s) - total harmonic distortion , topology (electrical circuits) , control theory (sociology) , converters , voltage , asynchronous communication , boost converter , changeover , redundancy (engineering) , computer science , engineering , electrical engineering , control (management) , telecommunications , artificial intelligence , operating system
The authors intent using a boost multi‐level converter for the doubly fed induction machine (DFIM) used in variable‐speed pumped storage plants (VS‐PSP). Voltage‐source converters connected on the rotor side of the machine control the active and reactive powers of the unit. The proposed boost neutral point clamped (NPC) converter topology provides a voltage output two times larger than a conventional three‐level NPC (3L‐NPC) with similar DC‐link voltage and equal number of switches. Hence, it increases the speed variation of the unit, which improves the efficiency during generation and pumping modes. Moreover, it reduces the starting period of the unit at the pumping mode, which is significant during mode changeover time. Furthermore, it reduces switching and conduction losses in the converter. It also reduces the total harmonic distortion in the output current, as it provides five output voltage levels. These improvements show that the boost NPC converter topology is better among VS‐PSP project authorities. In addition, the reliability of the proposed topology is investigated, where converter redundancy is a challenging issue in asynchronous VS‐PSP units. The proposed boost NPC was compared with the conventional 3L‐NPC system by examining a 250 MW DFIM hydro‐generating unit.