Compact Electric Power System for Fusion Reactor

Abstract

The issue of the Tokamak fusion reactor is its large area occupied by its power supply, which is about half of the total building area for the International Thermonuclear Experimental Reactor (ITER), together with the compatibility between the site grid and Tokamak loads during the plasma operation period. ITER is now implemented with Tokamak, which requires about 1 GVar reactive power to compensate its power system for superconducting magnets where about 0.2 GVar is transferred from France Electrical Power Network, the other 0.75 GVar is generated by the system of reactive power compensation and harmonic filtering, the standard VSC configuration. ITER can experimentally generate 500-MW fusion thermal power in 400 s long pulse mode. It could only generate about 500 MW/3 = 167 MWe active electric power if it is to be configured with pressured water reactor due to the fact that it is only about 1/3 conversion efficiency from thermal energy to electric energy. For such fusion machine, the requirement for reactive power is much larger than the active power it generates. Based on this requirement, one efficiency and compact pulsed synchronous generator is suggested for this purpose. It can generate not only the fundamental reactive power to compensate and stabilize the power network with low internal impedance but also the active power for outputting power to the network with exciting controller of the generator. Due to its two purposes in one device configuration, it becomes compact and reliable by being implemented in the design of future fusion power plant for demonstration. Some consideration has been done to the special low impedance synchronous generator, which is intended for the concept design of Chinese Fusion Engineering Testing Reactor, targeting the compact electric power system for superconducting Tokamak fusion reactor.