A specification theory combines notions of specifications and implementations with a satisfaction relation, a refinement relation and a set of operators supporting stepwise design. We develop a complete specifification framework for real-time systems using Timed I/O Automata as the specification formalism, with the semantics expressed in terms of Timed I/O Transition Systems. We provide constructs for refinement, consistency checking, logical and structural composition, and quotient of specifications --- all indispensable ingredients of a compositional design methodology. The theory is implemented on top of an engine for timed games, Uppaal-tiga, and illustrated with a small case study.

A new approach to performance validation of finite control set model predictive control (FCS-MPC) regulated power electronics converters is presented in this paper: statistical model checking (SMC). SMC is an established method used in various sectors of industry to provide solutions to problems that are beyond the abilities of classical formal techniques. The method is simple for implementation and requires only an operational system model that can be simulated and checked against properties. The approach will be presented on a standard two-level voltage source converter regulated by the FCS-MPC algorithm. In UPPAAL SMC toolbox, the converter system and controller are modeled as a network of stochastic timed automata. To assess the quality of the model, an equivalent Simulink model is used as a benchmark model. Using the model created in UPPAAL SMC toolbox the performance of the FCS-MPC algorithm is verified. The control algorithm is also tested on an experimental setup. During the evaluation, no significant degradation of reference tracking was found during transients nor under model parameter uncertainty.