Leakage Inductance Numerical Calculation And Characteristic Study Of Magnetically Controlled Saturated Reactor

The magnetically controlled saturated reactor (MCSR) is increasingly used in reactive power compensation field of EHV and UHV power network with its advantages of reliability, stability, simplicity, being controlled flexibly, and adjusting reactive power smoothly. Now days, our nation has been on the EHV and UHV transmission system, and hopes the technology of MCSR mature as early as possible. Breakthrough of 500kV grade MCSR becomes the target of MCSR designers.In this thesis, the electromagnetic parameters and electromagnetic characteristics of 500kV MCSR are deeply studied by the field and the circuit methods.Firstly, the body structure of 500kV MCSR is illustrated and the working principle is analyzed simply.Secondly, the 3-D finite element method model for the 500kV MCSR was established. The saturated leakage inductances under the excitation conditions were accurately calculated and the change rule was also got in accordance to the FEM model.Thirdly, a 500kV MCSR was taken as an example and the 2-D field-circuit coupled time-stepping finite element method model for the parallel MCSR was established. On the basis of above, MCSR was quantitatively calculated and the working current waveforms were got under different controlling current conditions. Subsequently, the electromagnetic characteristic curves of the MCSR, such as the controlling characteristic, the harmonic characteristic and the volt-ampere characteristic, were achieved by dealing with the working current waveforms under different controlling current.Finally, current decomposition approach is proposed and a relatively simple mathematical model that can manifest the electromagnetic law exactly is deduced. Subsequently, the equivalent circuit corresponding to the mathematical model is derived by using saturated transformer as the key component. Based on the mathematical model and the equivalent circuit, a simulation model for the 500kV MCSR is established in the PSB of MATLAB and the calculation of the working current under different controlling current conditions is demonstrated. The simulation results were identical with the FEM calculation results, so the accuracy of the methods was testified.