Passivity-Based Analysis of Sampled and Quantized Control Implementations
For control engineers, this work offers a theoretical framework to ensure stability when implementing continuous controllers on digital hardware with sampling and quantization.
The paper analyzes how sampling and quantization degrade passivity indices in continuous controllers implemented on digital devices, providing conditions for state boundedness in feedback systems. Examples illustrate the theoretical results.
This paper studies the performance of a continuous controller when implemented on digital devices via sampling and quantization, by leveraging passivity analysis. Degradation of passivity indices from a continuous-time control system to its sampled, input and output quantized model is studied using a notion of quasi-passivity. Based on that, the passivity property of a feedback-connected system where the continuous controller is replaced by its sampled and quantized model is studied, and conditions that ensure the state boundedness of the interconnected system are provided. Additionally, the approximate bisimulation-based control implementation where the controller is replaced by its approximate bisimilar symbolic model whose states are also quantized is analyzed. Several examples are provided to illustrate the theoretical results.