Infeasibility Analysis of Half-Wavelength Transmission Systems

Abstract

This paper analyzes the infeasibility of half-wavelength transmission systems in the aspects of power-frequency overvoltage and synchronization stability. The circuit model of the long-distance transmission system is established at first for steady-state and transient analysis. The sending-end system and the receiving-end system are both considered in the model. A test system based on an actual transmission line is given to facilitate the description of system characteristics. Based on the circuit model, the resonant transmission distance of the system is found and calculated. Theoretical analysis and numerical calculations are carried out to determine the feasibility transmission distance. It is demonstrated that the transmission distance should be in a certain range, which is larger than the resonant transmission distance, to satisfy the steady-state overvoltage and the small signal synchronization stability as well as the frequency deviation constraints. For transmission distances in the feasible range, the three-phase short circuit fault at a certain point of the transmission line will cause the most serious transient power-frequency overvoltage, and the system is very likely to lose synchronization stability. Considering the transient power-frequency overvoltage and the transient synchronization stability, the half-wavelength transmission system is technically impossible to operate.

Power Transmission Lines: Worldwide Research Trends

“…Some authors propose a fault location method for HWTLs in order to ensure safe and reliable operation [88]. Nowadays, some authors analyze the infeasibility of this approach [89].…”

Study on the Power-Frequency Waves Distribution Characteristics for Half-Wavelength Transmission Lines Based on the Frequency-Length Factor

“…Half-wavelength power transmission refers to the longdistance three-phase AC transmission technology. e electrical distance of a half-wave length transmission line (HWTLs) is close to half of the power-frequency wavelength (3000 km for 50 Hz systems and 2600 km for 60 Hz systems) [1][2][3][4]. Compared with HVDC lines [5][6][7] or highly compensated AC lines [8], half-wavelength power transmission technology has an advantage with no requirement of compensation, which may be the most economical solution for ultra-long distance power transmission [9][10][11].…”