KiteControllers

Build Status Coverage

Discrete controllers for kite power systems.

This package is part of Julia Kite Power Tools, which consist of the following packages:

Installation

using Pkg
pkg"add KiteControllers"

This package provides

Utility functions

saturate(value, min_, max_)

Calculate a saturated value, that stays within the given limits.

wrap2pi(angle)

Convert an angle, given in radian in an infinite range to the range from -pi to pi

Generic control components

This package contains some generic control components and are documented here.

Types that are not generic

FlightPathController    # represents the flight path controller
WinchController         # represents the winch controller
CalcVSetIn              # component that calculates the set speed using soft switching
FPCSettings             # settings of the flight path controller
WCSettings              # settings of the winch path controller
KiteModel               # simplified model for unit testing
WinchModel              # simplified model for unit testing

Flight path controller

FlightPathController as specified in chapter six of the PhD thesis of Uwe Fechner.

FlightPathController
FPCSettings
on_control_command(fpc, attractor=nothing, psi_dot_set=nothing, radius=nothing, intermediate = true)
on_est_sysstate(fpc, phi, beta, psi, chi, omega, v_a; u_d=nothing, u_d_prime=nothing)
on_timer(fpc)
calc_steering(fpc, parking)

The control commands are usually recived from the FlightPathPlanner, the output of the model or the system state estimator must call on_est_systate() each timestep.

Scientific background

Flight path control of kite power systems in a turbulent wind environment

Winch controller

WinchController

For a kite power system, the reel-out speed of the winch must be controlled such that the maximal tether force is never exceeded, while the reel out speed should be optimized for maximal power over the full cycle at wind speeds below rated wind speed. To keep the kite controllable, also a minimal tether force limit has to be kept. Depending on the mode of operation, one of the following three controllers is used:

Speed Controller

Lower Force Controller

Upper Force Controller

Scientific background

A Methodology for the Design of Kite-Power Control Systems Chapter 6.3 Winch control (WC)