Application And Research Of HVDV Flexible In Wind Power

With the rapid development of the world economy, the human’s production and life consume energy more and more. Relying solely on the traditional non-renewable energy obviously can not meet the needs of the human.Today, the more and more serious problem of societal energy crisis, and the growing awareness of the human environmental,all make countries in the world put forward higher requirements for environmental and ecology protection due to the exploitation and consumption of energy,Therefore the development of new energy is imminent. Wind power as a clean energy, is not only abundant, but green, renewable, inexhaustible. With the continued development of the technology, the wind power generation becomes an increasingly important role in the energy supply at home and abroad. In recent years, countries around the world built wind power plants of various sizes on land and sea. However the wind farm is generally far away from the user’s centralized electricity area, energy often requires long-distance transmission. HVDC-Flexible as a new type of transmission technology, has its unique varieties of advantages in wind power, such as independent decoupling in active and reactive power control,supplying power directly to the passive network such as silos, the power flow flipping, without the need for reactive power compensation, playing an isolated voltage fluctuations from wind farms and grid and so on. With power electronics technology continuous and PWM technology developing, HVD C-Flexible application in wind power is more widely.Based on HVDC-Flexible technology application in wind power, this thesis introduces HVDC-Flexible system components, voltage source inverter topology,analyzes its modulation principle, establishes its mathematical model of the steady-state and transient, studies its control strategies and AC and DC side harmonics, and gives the filter structure and the corresponding device parameters and selection methods, meanwhile according to reactive power compensation,wind power grid frequency, voltage control and ability to penetrate requirements, and so on, design the rectifier and inverter station control system, the mathematical model and gives the controller and the PI regulator design methods in wind power applications, and bases on the above mathematical models and control methods, establishes a wind farm HVDC-Flexible simulation system to the active network and passive network powered, verified the above theory and simulate from the steady-state, failure, filtering,flow fliping, wind energy mutations, load-side load mutations and other aspects, simulation results basically reached the expected effect of the design.