TESTING OF THE HF GENERATOR OF THE ICR PLASMA HEATING SYSTEM OF THE KTM TOKAMAK FOR AN EQUIVALENT ACTIVE LOAD

In most tokamaks, additional heating or extra power input is used to achieve the necessary plasma parameters such as temperature, confinement time, etc. This makes it possible to address current scientific challenges and conduct advanced research. The KTM tokamak will implement additional power input into the plasma using ion-cyclotron heating, as specified in the design. The additional plasma heating system on the KTM consists of four identical high-frequency generators, each with a capacity of 2 MW. No other systems for additional power input and plasma heating are provided on the KTM tokamak. Before operating such systems in normal mode, debugging and testing are conducted using load equivalents. This article presents the calculation of an active load equivalent. Based on the calculation results, the shape and geometric dimensions that ensure the absorption of up to 300 kW of high-frequency power are determined. The dimensions and main parameters of the load equivalent design for the additional high-frequency plasma heating system of the KTM tokamak have been determined. The calculations were carried out based on the assumption that the most preferable option is to create the load equivalent in the form of a resonator with an absorber made of saline aqueous solution. Experimental results from debugging using the developed active load equivalent are also presented. It has been demonstrated that with the developed load equivalent, it is possible to successfully carry out the necessary tests and adjustments of a high-power generator, and to prepare the additional power input system on the KTM tokamak for further debugging and switching to operation under plasma load.

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