Non-Linear Control for Floating Wind Turbines: Using Reset Control to overcome non-minimum phase zeros

As the world is shifting away from fossil fuel-based electricity production, mainly due to concerns for man-made climate change, a sharp rise in demand for wind powered electricity production is seen. In order to meet future demand, the vast amount of off-shore wind resources can be unlocked. A key technology for this task are floating wind...

Noise robustness improvement of reset control systems using measurement line filtering

Inherent limitations of linear control, including PID, are Bode's phase-gain relationship and the waterbed-effect. Literature showed that reset control can overcome these limitations. The 'Constant in Gain, Lead in Phase' (CgLp) reset element was developed, which can be used in combination with a conventional PID approach. The benefit is that...

Hybrid passivity and finite-gain properties of reset systems: An application to stability analysis in the frequency domain

Reset control is a "simple" nonlinear control strategy that has the potential of being widely adopted and improving the performance of systems traditionally controlled with PIDs. Lack of suitable methods for proving stability, that are in line with the current industrial practice, hampers the wider acceptance of reset control. In this thesis,...

Damping Analysis of Reset Control Systems: an Analytical Approach

The high-tech industry continuously pushes the boundaries of controller performance to achieve faster and more precise machines. Currently, linear control is the standard in the industry. These controllers suffer from the waterbed effect and Bode's phase/gain relation, which impose inherent limitations on the precision and robustness of the...

Tuning a Novel Reset Element through Describing Function and HOSIDF Analysis

The high-tech industry is pushing the motion system technology towards faster, more precise and more robust system. One of the keys to this growing demand is the advancement of motion control. To this day, Proportional-Integral-Derivative (PID) has been the workhorse for the industry system control. This is because PID is simple to design and...

Tuning of the ‘Constant in gain Lead in phase’ Element for Mass-like Systems

The development of the high-tech industry has pushed the requirements of motion applications to extremes regarding precision, speed and robustness. A clear example is given by the wafer and reticle stages that require rigorous demands like robust nanometer precision and high-speed motion profiles to ensure product quality and production...

Reset Control for Vibration Isolation

Floor vibrations are a common problem in high tech engineering where good tracking, precision and bandwidth have utmost importance. They are mainly present at low frequencies, and they need to be suppressed. PID control is the go-to controller in the industry because of its ease of design, simple implementation and good performance. However, PID...

Robust Reset Control using Adaptive / Iterative Learning Control

Reset controllers can outperform PID controllers and may introduce phase advantage compared to linear PID control. However, in general, reset controllers do not have the same steady state properties as linear controllers, like removing steady state errors. In case of model mismatches and disturbances, this may cause limit cycles (persisting...

Improving the noise robustness of reset controllers with an observer

The performance of linear control is limited by the waterbed effect, while the performance demands of industry are continuously increasing. Using non-linear control in the future is therefore unavoidable. Being non-linear, reset control is able to achieve better performance than linear control. However, the lack of robustness to measurement...

Overcoming inherent performance limitations in industrial motion stages with reset control: A general approach to the design and implementation of reset controllers validated on an ASMPT AB383 wire bonder

Linear time-invariant controllers are undoubtedly the most popular type of regulators used in industrial applications, with the overwhelming majority of companies employing them. The reason is mainly given by their simple design methods. In particular, frequency domain predictive performance analysis and stability methods allow the use of...

Proposed solutions for quantization induced performance deterioration in reset controllers

The most widely applied feedback controller is PID. This controller gains its popularity because of the ease of design through loop shaping, since PID can be analyzed in the frequency domain. However, PID is limited by linearity. Reset control is a nonlinear addition to PID control. Through linearization techniques it can be designed by...

Automated Reset Controller Design with a Novel Structure for Improved Performance of an Industrial Motion Stage

Linear time-invariant (LTI) controllers suffer from inherent limitations as the waterbed effect and Bode's gain-phase relationship. Reset control, a nonlinear strategy involving the reset of linear controllers, offers a potential solution to overcome these traditional LTI limitations. Based on the describing function analysis, the reset...