An ANPC converter design using ST20 for high-power offshore wind application

Abstract:
In order to pursuit lower system cost and higher energy efficiency, power of single wind turbine is becoming higher and higher. For offshore wind application, 8~10MW wind turbine is becoming a common practice. To address this demanding market, power modules with higher power density are needed. This paper presents a high reliable power module named ST20 which is designed by Semikron and very suitable for offshore wind converters because of its unparalleled design, such as low stray inductance, high current capability, excellent current sharing of module paralleling and easy DC-link connection. This paper also illustrates the benefits of ANPC topology for high power application, and investigates the feasibility of ST20 module used in an ANPC 10MW converter by simulation study. Furthermore, a 3-level reference design helps to illustrate that ST20 module is an excellent solution for high power offshore wind application with improved reliability.