Desenvolvimento de estratégia em hardware para o controle do nível de tensão nos capacitores do conversor multinível modular

• Autor(a) principal: Nunes, Weder Tótola
• Data de Publicação: 2018
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/9723
• topic: Conversores multiníveis; Engenharia Elétrica; Modulação de duração do pulso; Transmutadores de fase; Arranjos de lógica programável em campo; Hardware; Capacitadores; 621.3

This thesis proposes a control of the voltage level in the capacitors that make up the modular multilevel converter, regardless of its application. To prove the developed voltage control strategy in the capacitors will be used the modular multilevel converter as Static Synchronous Compensator (STATCOM). In this case, two control strategies are presented for the converter. The first strategy, focused on the voltage level control at the common connection point, typical of a STATCOM, uses the coordinate transformation, Clarke's transform, and the instantaneous power theory for the general control of active and reactive power of the converter. The second strategy for controlling the voltage level in the capacitors that make up the modular multilevel converter uses the Phase Shifted Pulse Width Modulation (PS-PWM) modulation, the capacitor voltages and the converter phase currents. The main contribution of this thesis is the second control strategy, a strategy developed to control the voltage level in the capacitors of the multilevel converter modules and that activates the semiconductor switches in order to select the most suitable capacitor to enter or leave operation. Several scenarios are analyzed that consider balanced and unbalanced loads, reference voltage variations of the connection point and capacitors, besides a low voltage model simulation. In order to experimentally validate the developed strategy for controlling the capacitors voltage level, are presented the laboratory results of the multilevel converter for a small scale, low voltage model, acting as an inverter to drive an electric load.