Study Of Current Source High-voltage Converter Using IGCT

It is obvious to AC drives using converters for efficiency and energy conservation. Due to the larger power and high reliability of current source converter(CSC), its applications become more and more. Increased research and development is of great significance for energy conservation and emission reduction in our country.First of all, this paper briefly introduces the key technologies and development of high-voltage converters, compares the various programs of high-voltage converter and points out their advantages and disadvantages. Secondly, this paper analyses and ascertains the structure of current-source converter:transformerless and double PWM modulatin of CSC with an integrated dc choke.The disadvantage.of converter with transformer is pointed out. In this paper, it also describes the principles and features of integrated dc choke which is used to suppress common-mode voltage in a motor drive and gives its design approach. In addition, this paper describes the series connection of IGCTs using RC-snubbers,and presents design principle about IGCT drive and hign isolation of the drive power supply. For the characteristics of the input and output filters of novel transformerless high voltage current source converter, according to LC filter equivalent circuits and harmonic characteristics of three-phase current based on Space Vector Modulation(SVM), a systematic and user-friendly approach is proposed.Through analysis and comparison of PWM modulation of CSC, their respective strengths and weaknesses and scope of use are given, in particular, a concrete realization method of SVM is decribed. Otherwise, a solution to avoid LC resonant—active damping control is given and it is confirmed by simulation.Then,a concrete realization method is presented about constant V/F control of AC motor. At last, this paper provides a kind of realization of the program of rated power 1MVA rated voltage 4160V CSC. The structure and function of CSC are described in detail.A 10kVA CSC prototype has set up and some experiments are carried out.