Defesa de Dissertação de Mestrado – Luiz Henrique Tonon Schmidt – 4/6/2020
03/06/2020 11:31
| Defesa de Dissertação de Mestrado | |
| Aluno | Luiz Henrique Tonon Schmidt |
| Orientador | Prof. Daniel Juan Pagano, Dr. – DAS/UFSC |
| Coorientador | Prof. Rony Cristiano, Dr. – PPGEAS/UFSC |
| Data | 4/6/2020 (quarta-feira) – 15 h
Videoconferência |
| Banca | Prof. Daniel Juan Pagano, Dr. – DAS/UFSC (presidente);
Prof. Marcelo Lobo Heldwein, Dr. – EEL/UFSC; Prof. Marcelo de Lellis Costa de Oliveira, Dr. – DAS/UFSC; Prof. Hector Bessa Silveira, Dr. – DAS/UFSC. |
| Título | Analysis and Design of Passive Capacitor Voltage Balancing in Modular Multilevel Converter during Precharge Operation |
| Abstract: The Modular Multilevel Converter (MMC) is a topology that has been increasingly attracting interest in research. Its is applied in High Voltage in Direct Current systems (HVDC), Medium Voltage Drives (MVD), and integration of renewable power sources to a grid. Some advantages of this topology are its modular design, based on the connection of submodules (SMs), which facilitates its manufacturing and maintenance, and possibility of operating without bulky transformers and output filters. It is advantageous that each SM local signal electronics circuits is self-powered by means of a power supply fed from the SM respective capacitor. This configuration, however, can lead to unbalanced and even unstable voltages during the precharge process. The balancing of the MMC’s capacitor voltages during its precharge stage is crucial to its correct operation. A passive balancing strategy consisting in adding a balancing resistance in parallel with each SM is analyzed in this work. An instantaneous piecewise smooth (PWS) nonlinear model is proposed. The system nonlinear dynamics are analyzed for a system with two SMs. Conditions for local stability of the operating point are obtained, and the results are extended for a system with an arbitrary number of SMs. The effects of variation of the balance resistance in the dynamics of the system is studied. Also, conditions for global stability are obtained for a system with two SMs, and some guidelines for the design of the balancing resistance are proposed. | |
