Mitigation of Negative Impedance Instabilities in a DC/DC Buck-Boost Converter with Composite Load

Abstract

A controller to mitigate the destabilizing effect of constant power load (CPL) is proposed for a DC/DC buck-boost converter. The load profile has been considered to be predominantly of CPL type. The negative incremental resistance of the CPL tends to destabilize the feeder system, which may be an input filter or another DC/DC converter. The proposed sliding mode controller aims to ensure system stability under the dominance of CPL. The effectiveness of the controller has been validated through real-time simulation studies and experiments under various operating conditions. The controller has been demonstrated to be robust with respect to variations in supply voltage and load and capable of mitigating instabilities induced by CPL. Furthermore, the controller has been validated using all possible load profiles, which may arise in modern-day DC-distributed power systems.

An Adaptive Passivity‐Based Controller of a Buck‐Boost Converter with a Constant Power Load

“…In addition, as it is widely acknowledged, the drawbacks of this method are that the proposed control law suffers from chattering and its relay action injects a high switching gain. The deleterious effect of these factors is clearly illustrated in experiments shown in [19], which exhibit a very poor performance.…”

“…However, the construction is based on feedback linearization that, as is well‐known, is highly non‐robust. A sliding mode controller is designed in for this problem. However, for the considered nonlinear system, the stability result is obtained by adopting the linear system theory.…”

Constant Power Loads (CPL) with Microgrids: Problem Definition, Stability Analysis and Compensation Techniques

“…The development of electronic switch devices has led to penetrations of power electronic applications in a power system [1,2], advanced control approaches, and more renewable energy sources [3], and on the other hand an increase in energy demands that has consequently led to increased environmental problems such as greenhouse gases being emitted from non-renewable energy sources [4,5]; all these factors have contributed to the appearance of new applications in power systems and have taken many forms in modern life [6]. One of these applications is the µgrid, a new concept for a power system.…”

Energy shaping control for buck–boost converters with unknown constant power load

“…However, the construction is based on feedback linearization that, as is well-known, is highly non-robust. A sliding mode controller is designed in [8] for this problem. However, for the considered nonlinear system, the stability result is obtained by adopting linear system theory.…”

“…In addition, as it is widely acknowledged, the drawbacks of this method are that the proposed control law suffers from chattering and its relay action injects a high switching gain. The deleterious effect of these factors is clearly illustrated in experiments shown in [8], which exhibit a very poor performance. In [16] an adaptive interconnection and damping assignment passivity-based controller (IDA-PBC) [11,13], with guaranteed stability properties, was proposed.…”