Research on Control Mode and Operating Characteristic of Novel HVDC Transmission System
|Keywords||Coupled Compensated and Shielding Harmonic Pole control New DC transmission system Collaborative Control|
The national grid interconnection is the inevitable trend of development of China's power grid . Building \State Grid Corporation of key construction of UHV power grid , the DC transmission suitable for long-range , high-capacity transmission of electricity , therefore UHV DC transmission will be widely used . The converter transformer is one of the most important equipment in the DC transmission system , auto compensation and harmonic shielding converter transformers advantages with traditional converter transformers are not available , has a very broad application prospects . The research in this paper is the use of the characteristics of this new type of converter transformers new DC transmission system control mode and run . This paper mainly include the following aspects: First, the principles and characteristics of the new converter transformer and its filter system , a brief analysis of Hunan University of transmission and distribution of new technologies related to research and development platform introduced . The new converter transformer unique auto- compensation and harmonic shielding function . Then , the study of the overall structure of the traditional HVDC control system , and the pole control systems focus the discussion . Principles and characteristics of the various controllers , and simulation , and analysis of the performance of various controllers disturbance when switching between controller actions and system stability , transient operating characteristics . Electromagnetic transient simulation tool PSCAD / EMTDC new HVDC transmission system model using the new converter transformer and its filter system , its operating characteristics under different failure modes , in order to verify the simulation model of rationality . Finally, synergetic control theory , and collaborative control strategy used in the new DC transmission system simulation model to analyze its operating characteristics in the case of start - up process , the DC current tuning value fluctuations , and the results with traditional PI control to illustrate the strategy better control effect .