Instantaneous Electromagnetic Torque Components in Synchronous Motors Fed by Load-Commutated Inverters

Energies

Gabriel Ekemb¹  Issouf Fofana²  P. M. Lingom³  Joseph Song-Manguelle⁴  Fouad Slaoui-Hasnaoui⁵ 

[1] Department of Applied Sciences, University of Quebec, Chicoutimi, QC G7H 2B, Canada;Department of Applied Sciences, University of Quebec, Chicoutimi, QC G7H 2B1, Canada;Department of Electrical Engineering and Automation, University of Fuzhou, Fuzhou 350116, China;Department of Electrical and Computer Engineering, University of Quebec, Trois-Rivières, QC G8Z 4M3, Canada;School of Engineering, University of Quebec, Rouyn-Noranda, QC J9X 5E4, Canada;

关键词: load-commutated inverter;    synchronous motor;    torsional vibrations;   

DOI  :  10.3390/en14113223

来源: DOAJ

【 摘 要 】

This paper proposes time-domain analytical expressions of the instantaneous pulsating torque components in a synchronous machine air gap when supplied by a load-commutated-inverter (LCI) system. The LCI technology is one of the most used variable frequency drives when very high power and low speed are required in applications such as pipeline recompression and decompression, as well as liquefied natural gas compression. In such applications, synchronous motors are used because of their high efficiency resulting from a separated supply of the current to their rotor through the excitation circuit. These applications usually have long and flexible shafts, which are very sensitive to torsional vibration excitation when their natural frequencies interact with any external torque applied to the shaft. A torsional analysis is required by international standards to assess the survivability of the shaft through the overall speed range of the motor. Therefore, the magnitude and frequencies of the motor air-gap torque are needed for such evaluation. The proposed developments are supported by numerical simulations of LCI systems in a large range of operation range. From the simulation results, torque harmonic families are derived and expressed in a parametric form, which confirm the accuracy of the proposed relationships.

【 授权许可】

Unknown