Vulnerability of a VOC-Based Inverter Due to Noise Injection and Its Mitigation

Even though virtual oscillator control (VOC)-based inverters do not communicate with each other, they need to make local measurements for control. The impact of tampering with these measured or sensed signals on the performance of a VOC-based inverter and synchronization of multiple such inverters is an important but open-ended issue. As such, this letter explores the impact of intentional side-channel noise intrusion (SNI) on the synchronization of VOC-based communication-free self-synchronizing inverters (CFSIs). Two different scenarios are investigated via experimental and analytical studies using a half-bridge neutral point clamped (NPC) single-phase CFSI. They address the impact of SNI on the ability of a CFSI to ensure a stable 60-Hz limit cycle and on the parallel operation of two such CFSIs to ensure synchronism to a common 60-Hz load frequency.

I. Introduction

Recently, the authors in [1] explored the impact of side-channel noise intrusion (SNI) on the performance of a communication-based inverter (CBI) and how such noise injection can lead to subsynchronous inverter output. While CBI has been the workhorse of the power-electronics industry, recently self-synchronizing communication-free self-synchronizing inverter (CFSIs), based on virtual oscillator control (VOC) [2], have gained traction. This is mainly because they operate in a decentralized fashion without information exchange and can scale in network size without their performances affected by communication latency.