Open Switch Fault Diagnosis and Current Sensor Fault Tolerant Control of a DC-DC Interleaved Boost Converter using Generalized Proportional Integral Observer

Fault diagnosis and fault-tolerant control are important and stringent in the research field of renewable energy systems. Interleaved Boost DC-DC converters are today widely used in different applications such as PV or fuel cell-based systems and usually are operated in closed-loop control.This paper proposes an open-switch fault diagnosis and current sensor fault-tolerant control of a DC-DC interleaved boost converter using a Generalized Proportional Integral Observer (GPIO). First, an observer model is designed in order to estimate the current sensor fault. When the current sensor fault is reconstructed, it is compensated in the closed-loop control. Then, the compensated currents are used to diagnose the open switch fault based on the converter's currents variations. The main advantage of the proposed approach is that it is able to diagnose power semiconductor faults even under faulty current measurements. The performance and robustness of the proposed technique are validated through simulation results.