Tesis doctoral de Edris Pouresmaeil
Distributed generation (dg) with a converter interface to the power grid is found in many of the green power resources applications. This dissertation describes a multi-objective control technique of voltage source converter (vsc) based on multilevel converter topologies, for integration of dg resources based on renewable energy (and non-renewable energy) to the power grid. the aims have been set to maintain a stable operation of the power grid, in case of different types of grid-connected loads. The proposed method provides compensation for active, reactive, and harmonic load current components. a proportional-integral (pi) control law is derived through linearization of the inherently nonlinear dg system model, so that the tasks of current control dynamics and dc capacitor voltage dynamics become decoupled. This decoupling allows us to control the dg output currents and the dc bus voltage independently of each other, thereby providing either one of these decoupled subsystems a dynamic response that significantly slower than that of the other. To overcome the drawbacks of the conventional method, a computational control delay compensation method, which delaylessly and accurately generates the dg reference currents, is proposed. The first step is to extract the dg reference currents from the sensed load currents by applying the stationary reference frame and then transferred into synchronous reference frame method, and then, the reference currents are modified, so that the delay will be compensated. the transformed variables are used in control of the multilevel voltage source converter as the heart of the interfacing system between dg resources and power grid. By setting appropriate compensation current references from the sensed load currents in control circuit loop of dg link, the active, reactive, and harmonic load current components will be compensated with fast dynamic response, thereby achieving sinusoidal grid currents in phase with load voltages while required power of loads is more than the maximum injected power of the dg resources. the converter, which is controlled by the described control strategy, guarantees maximum injection of active power to the grid continuously, unity displacement power factor of power grid, and reduced harmonic load currents in the common coupling point. In addition, high current overshoot does not exist during connection of dg link to the power grid, and the proposed integration strategy is insensitive to grid overload.
Datos académicos de la tesis doctoral «Advance control of multilevel converters for integration of distributed generation resources into ac grid«
- Título de la tesis: Advance control of multilevel converters for integration of distributed generation resources into ac grid
- Autor: Edris Pouresmaeil
- Universidad: Politécnica de catalunya
- Fecha de lectura de la tesis: 27/03/2012
Dirección y tribunal
- Director de la tesis
- Daniel Montesinos Miracle
- Tribunal
- Presidente del tribunal: johan Driesen
- Fernando Bianchi (vocal)
- (vocal)
- (vocal)