activity
20242026
collaborators

7 papers

math.OC2026

On the solvability of parameter estimation-based observers for nonlinear systems

Bowen Yi, Leyan Fang, Romeo Ortega

Parameter estimation-based observer (PEBO) is a recently developed constructive tool to design state observers for nonlinear systems. It reformulates the state estimation problem a…

eess.SY2025

Some Reflections on Sliding Mode Designs in Control Systems: An Example of Adaptive Tracking Control for Simple Mechanical Systems With Friction Without Measurement of Velocity

Romeo Ortega, Leyan Fang, Jose Guadalupe Romero

The objective of this note is to share some reflections of the authors regarding the use of sliding mode designs in control systems. We believe the abundant, and ever increasing, a…

eess.SY2025

A New Partial State-Feedback IDA-PBC for Two-Dimensional Nonlinear Systems: Application to Power Converters with Experimental Results

Rafael Cisneros, Leyan Fang, Wei He +1

In this paper we propose a variation of the widely popular Interconnection-and-Damping-Assigment Passivity-Based Control (IDA-PBC) based on Poincare's Lemma to design output feedba…

eess.SY2025

Adaptive Compensation of Nonlinear Friction in Mechanical Systems Without Velocity Measurement

Jose Guadalupe Romero, Romeo Ortega, Leyan Fang +1

Friction is an unavoidable phenomenon that exists in all mechanical systems incorporating parts with relative motion. It is well-known that friction is a serious impediment for pre…

eess.SY2025

Interturn Fault Detection in IPMSMs: Two Adaptive Observer-based Solutions

Romeo Ortega, Alexey Bobtsov, Leyan Fang +2

In this paper we address the problem of online detection of inter-turn short-circuit faults (ITSCFs) that occur in permanent magnet synchronous motors (PMSMs). We propose two solut…

eess.SY2025

Voltage Control of the Boost Converter: PI vs. Nonlinear Passivity-based Control

Leyan Fang, Romeo Ortega, Robert Griñó

We carry-out a detailed analysis of direct voltage control of a Boost converter feeding a simple resistive load. First, we prove that using a classical PI control to stabilize a de…