Design and Implement a Digital H∞ Robust Controller for a MW-Class PMSG-Based Grid-Interactive Wind Energy Conversion System

Abstract

A digital H ∞ controller for a permanent magnet synchronous generator (PMSG) based wind energy conversion system (WECS) is presented. Wind energy is an uncertain fluctuating resource which requires a tight control management. So, it is still an exigent task for the control design engineers. The conventional proportional-integral (PI) control is not ideal during high turbulence wind velocities, and the nonlinear behavior of the power converters. These are raising interest towards the robust control concepts. The robust design is to find a controller, for a given system, such that the closed-loop system becomes robust that assurance high-integrity and fault tolerant control system, robust H ∞ control theory has befallen a standard design method of choice over the past two decades in industrial control applications. The robust H ∞ control theory is also gaining eminence in the WECS. Due to the implementation complexity for the continuous H ∞ controller, and availability of the high speedy micro-controllers, the design of a sample-data or a digital H ∞ controller is very important for the realistic implementation. But there isn't a single research to evaluate the performance of the digital H ∞ controller for the WECS. In this paper, the proposed digital H ∞ controller schemes comprise for the both generator and grid interactive power converters, and the control performances are compared with the conventional PI controller and the fuzzy controller. Simulation results confirm the efficacy of the proposed method Energies 2013, 6 2085 which are ensured the WECS stabilities, mitigate shaft stress, and improving the DC-link voltage and output power qualities.

An Optimal Integrated Control Scheme for Permanent Magnet Synchronous Generator-Based Wind Turbines under Asymmetrical Grid Fault Conditions

“…However, the PR controller is difficult to realize in practical engineering and its stability decreases during disturbances because of the narrow bandwidth. To overcome the disadvantages of PI and PR controllers, the quasi proportional resonant (Quasi-PR) controller [30,31] is employed in this paper to design the second harmonic compensation control loop.…”

“…Furthermore, a Quasi-PR controller can still achieve zero steady-state error during grid disturbances because of its relatively wide bandwidth, such as asymmetrical faults in grid, which improves the drawbacks of PR controller [30,31]. Therefore, the Quasi-PR controller is adopted to control the double frequency components P 2 and Q 2 in this paper.…”

Residue Theorem based soft sliding mode control for wind power generation systems

“…The wind is a source of energy which is highly affected by the uncertain fluctuations. As a result, wind power generation system can be described as a complex nonlinear system operates in highly uncertain environments which demand a tight control management [2]. The control system of WPGS plays an important role to affect the amount of extracted power from wind.…”

Particle swarm optimization tuned fuzzy terminal sliding mode control for UPS inverters

“…For system (6), the control law u can be expressed as follows: (11) where the equivalent control term u e is valid only on the sliding surface, and is defined as follows:…”

“…However, a PID controller cannot achieve satisfactory performance when the controlled plant experiences highly nonlinear loading [5,6]. Several control methods have been employed, such as H-infinity control, repetitive control, and multi-loop control, but they are difficult to realize, and their algorithms are extremely complex [4,7,11]. Sliding mode control (SMC) is intrinsically robust against system uncertainties [15].…”