Study On Operation Of A Direct-Driven Permanent Generator System Using Matrix Converter

More attention has been paid to the wind power generation due since the wind energy is a"green"and cheap renewable energy source. The rendency of modern wind power technology is brushless and gearless without gearbox between the turbine and generator. The low speed permanent magnet (PM) generator direct driven by wind turbine is a typical one to meet the above requirements. Due to the simple structure and high reliability, large size, the low speed PM wind generators are particularly suitable for China's wind resource-rich features and have wide application prospect.Compared with the traditional AC-DC-AC converter, as a new AC-AC converter, matrix converter (MC) has the following significant advantages: no medium DC link, fast transient response; large energy transmission density, small volume; adjustable input power factor; easy realization of four quadrant running etc., so the MC is a new type of converter which has excellent control performance. With the development of high power electronic device and further study on the control methods, the MC will produce profound significance on Energy, electric transmission and high-performance servo control and other fields.In this article, the fundamental principles of the MC space vector modulation (SVM) are explored, and the MC mathematical model is established. Also, the article analyses the PM field-oriented vector control strategy, and establishes the mathematical model and the steady-state equivalent circuit of PM generator. On this basis, the grid-connected system simulation model using the MC is established. The system simulation results show the decoupling property between active and reactive power, and the correctness and feasibility of the proposed system in the article is verified.It is proposed that a high-performance MC control system design scheme with DSP as main processor and FPGA as coprocessor. By proper functional division of SVM and four-step commutation, the MC experiment platform is designed and implemented successfully. A new direct driven PM generator system is constructed eventually, and the input and output characteristics are tested. The experimental results show that the output voltage, current and input power factor are controllable through PM field-oriented vector control of the generator and space vector modulation of MC. The experimental foundation is established for further study and work.