In this paper,we propose a modular multilevel converter(MMC)with a wireless magnetic power decoupling approach suitable for medium-voltage high-power variable-speed machine drives.Our proposed power decoupling approac...In this paper,we propose a modular multilevel converter(MMC)with a wireless magnetic power decoupling approach suitable for medium-voltage high-power variable-speed machine drives.Our proposed power decoupling approach is independent of the operating frequency,which solves the issue of wide fluctuations of low-frequency voltage ripple components in submodule(SM)capacitors,especially at low-speed operations without using any ripple power capacitor.Employing wireless magnetic elements reduces the amount of high-voltage insulation between the transformer windings,resulting in a significant reduction in the overall size of the system.The basic idea of our proposed approach is to magnetically couple the instantaneous three-phase ripple power of each of the three adjacent-arm SMs.The proposed MMC is free from low-frequency capacitors,resulting in enhanced system reliability,volume,and lifetime.The operation principles of the proposed MMC are explained,and a control design is introduced.The performance of the proposed scheme was verified via simulation and experimental tests.展开更多
基金This work was supported by the National Research Foundation of Korea(NRF)funded by the Korea government(MEST)under Grant NRF2019R1A2C108460511.
文摘In this paper,we propose a modular multilevel converter(MMC)with a wireless magnetic power decoupling approach suitable for medium-voltage high-power variable-speed machine drives.Our proposed power decoupling approach is independent of the operating frequency,which solves the issue of wide fluctuations of low-frequency voltage ripple components in submodule(SM)capacitors,especially at low-speed operations without using any ripple power capacitor.Employing wireless magnetic elements reduces the amount of high-voltage insulation between the transformer windings,resulting in a significant reduction in the overall size of the system.The basic idea of our proposed approach is to magnetically couple the instantaneous three-phase ripple power of each of the three adjacent-arm SMs.The proposed MMC is free from low-frequency capacitors,resulting in enhanced system reliability,volume,and lifetime.The operation principles of the proposed MMC are explained,and a control design is introduced.The performance of the proposed scheme was verified via simulation and experimental tests.
