Selecting IGBT module for a high voltage 5 MW wind turbine PMSG-equipped generating system

Abstract

In this paper, a fairly high voltage generating system for a 5 MW generating system is investigated. The generating system consists of a surface mounted PMSG (Permanent Magnet Synchronous Generator) with a 2-level transistor converter. The focus is on utilizing three available high voltage IGBT-modules, and to investigate the resulting losses when using them to compose a converter, in order to observe the difference as well as the best choice. In addition, the ideal dc-link voltage for a certain module as well as for a certain main average wind speed is studied. It is found that the most suitable module to use from the loss point of view is the 1.7 kV module, the one with the lowest voltage rating. The difference towards using the 6.5 kV module is a loss increase in the converter at rated operation of 62 %. This is in spite of that a converter composed of the 6.5 kV module has less than half of the conduction losses compare to 1.7 kV module. Accordingly, it can be understood that the switching losses increase much stronger than the conduction losses decrease when using a module with higher voltage rating. When looking at the average annual energy efficiency difference, the best annual efficiency is also achieved when the converter is composed with the 1.7 kV modules.Index Terms-wind energy, energy efficiency, power electronic 2-level converter, IGBT, permanent magnet synchronous generator, dc-link voltage.

Thermal loading of wind power converter considering dynamics of wind speed

“…For the nominal network line-to-line voltage of 690 V, IGBTs with a 1700 V rating are required [6]. The IGBT rating of 6500 V entails 62% total loss increase of the 2-level converter at the same current rating [7]. In the 3L-NPC and 3L-ANPC, the voltage rating of individual power device can be lower than in the 2-level converter.…”

Coordinated power dispatch of a PMSG based wind farm for output power maximizing considering the wake effect and losses

“…The q-axis current is proportional to the generator torque. The d-axis current is controlled to be zero to maximize the torque [30]. The copper loss can be calculated using…”

“…Where el  is the electrical speed of the machine and 1 k is a constant extracted from the iron losses at rated speed, and is found to be 0.1 [30].…”

IGBT Applications

“…Their preferred IGBT structure has a trench gate architecture as shown in Fig. The case of a 5 MW wind power installation using a10 kV DC bus voltage has been analyzed from the point of view of using either 1700 V or 3300 V or 6500 V IGBT modules [42]. The trench gate structure was found to have on on-state voltage drop of 3.7 V which is 1.6 V less than that for the planar gate design.…”