Signal Noise and Discretisation

When a discrete external controller is used, Bladed offers the possibility of adding random noise to the measured signals sent to the controller, and also to discretise the signals to a specified resolution.

The random noise may be Gaussian, in which case the standard deviation of the noise must be specified, or it may be from a rectangular distribution, in which case the half-width of the distribution should be given. The noise is added to the signal before it is discretised.

On top of that, first order lag models are also provided in Bladed to represent the dynamics of any measured signal, including the power and generator speed transducers. The first order lag model is represented by:

\[ \begin{equation} \dot{y} = \frac{1}{T}(u-y) \end{equation} \]

where \(T\) is the time lag constant, \(u\) is the input and \(y\) is the output. The input is the actual power or speed and the output is the measured power or speed, as input to the controller.

The second order lag model is represented by:

\[ \begin{equation} \ddot{y} + 2 \zeta \dot{y} + \omega^2 = \omega^2 u \end{equation} \]

Where \(\omega\) is the angular frequency, and \(\zeta\) is the damping coefficient.

Last updated 08-10-2024