编辑: 思念那么浓 | 2015-02-15 |
Comp Sci () : C c T¨ UBB ITAK doi:10.
3906/elk- A control scheme for maximizing the delivered power to the load in a standalone
1 wind energy conversion system
2 Saeed HESHMATIAN, Davood ARAB KHABURI? , Mahyar KHOSRAVI, Ahad KAZEMI Department of Electrical Engineering, Iran University of Science and Technology (IUST), Tehran, Iran Received: .201 ? Accepted/Published Online: .201 ? Final Version: ..201
3 Abstract: In this paper, a control scheme is proposed for maximum power point tracking (MPPT) in a variable speed
4 standalone wind energy conversion system (WECS) with permanent magnet synchronous generator (PMSG). A MPPT
5 algorithm is designed trying to eliminate the main de?ciency of the conventional perturbation and observation (P&
O)
6 method which is the challenge of choosing a proper step size and the unwanted tradeo? between accuracy and speed.
7 The designed algorithm properly addresses this drawback and signi?cantly improves the MPPT performance. Another
8 important issue is to ensure fast and accurate tracking of the optimal reference point obtained from the MPPT algorithm
9 and improve the performance and e?ciency of the control system for transferring maximum possible power to the load.
10 To this end, Vienna recti?er is used in the designed WECS and a multi-objective model predictive control (MPC) scheme
11 is designed to properly control the converter with fast response, high accuracy and at the same time, with the lowest
12 possible switching frequency. The performance of the proposed control scheme has been studied for two di?erent wind
13 speed pro?les with di?erent behaviors. Moreover, a comparison is made between the proposed MPPT algorithm and
14 the conventional P&
O method. The results approve the proper performance of the proposed system in extraction and
15 transfer of the maximum possible power from the wind to the load. This aim is achieved because of the signi?cant
16 advantages of the designed system in terms of fast and accurate tracking of optimal point and having higher e?ciency.
17 Key words: Maximum power point tracking, multi-objective model predictive control, wind energy conversion system,
18 switching frequency reduction, Vienna recti?er
19 1. Introduction
20 There are various forms of renewable energy resources and wind energy is undoubtedly among the most
21 important and promising ones. In addition to the wind turbine and the electrical generator, which are the main
22 parts, a proper converter interface and its control system are also necessary in a wind energy conversion system
23 (WECS). Permanent magnet synchronous generator (PMSG) is the dominant technology in these systems due to
24 its notable advantages such as high e?ciency and high power density, good reliability and low maintenance [1, 2].
25 A power electronic interface is required for connecting a WECS to the electrical load or power network. This
26 interface mainly consists of a recti?er and an inverter which are called the generator- and grid-side converters,
27 respectively.
28 Classical six-switch recti?er is widely used as the generator-side converter in WECSs because of its
29 simplicity. However, this converter does not provide satisfactory performance and has some major drawbacks
30 such as high harmonic distortion and low e?ciency. In this work, the Vienna recti?er is utilized in the studied
31 ?Correspondence: [email protected]
1 HESHMATIAN et al./Turk J Elec Eng &
Comp Sci WECS in order to improve the performance of the system. This topology was introduced for being utilized in