Improved conditions for observer-based LPV control with guaranteed ℒ2-gain performance

Synthesis of observer-based LPV controllers is considered with a guaranteed upper bound on the worst-case energy gain from the disturbance input to the performance output. A potentially conservative solution was derived for this problem before based on LMI optimization accompanied with a line search over a scalar variable. A new solution is provided in this paper based on a similar optimization problem, which has a comparable level of off-line computational complexity. It is shown that the new method cannot be any more conservative than the existing one. It is also verified by an example that the new solution can actually provide less conservative results. Another desirable feature of the new solution is that it is better suited for multi-objective synthesis.