Greetings,
As explained in the documentation, an Algebraic loop is a set of components that form a loop where an output of each component is connected to a direct feedthrough input of the next one. In the case of the model in the figure you attached, the Integrator and comparator ports are both direct feedthrough and, as such, form an algebraic loop.
To fix this, a simple Unit delay component should be added between the Integrator and the comparator.
