Advanced DC zonal marine power system protection

Abstract

Abstract--A new Active Impedance Estimation (AIE) based protection strategy which is suitable for utilization in a DC zonal marine power distribution system is presented. This method uses two triangular current "spikes" injections for system impedance estimation and protection when faults are detected. By comparing the estimated impedance with the pre-calibrated value, the fault location can be predicted and fault can be isolated without requiring communication between two injection units. Using cooperated double injections and line current measurement (directional fault detection), faults in the system with same impedance and different fault positions can be distinguished, located and isolated. The proposed method is validated using experimental test results derived from a 30kW, 400V, twin bus DC marine power system demonstrator. The experimental tests were applied to both faults during normal operation and faults that occur during system restoration.

System Configuration, Fault Detection, Location, Isolation and Restoration: A Review on LVDC Microgrid Protections

“…In general, the techniques of fault location can be divided into two types: online methods and offline methods. Most of the existing techniques for locating fault primarily are based on offline based methods [24,[104][105][106]. These methods usually employ a probe to inject current or voltage signals to the main circuit and identify the fault location by detecting the electrical response to the injected signals.…”

Analysis and Design of DC System Protection Using Z-Source Circuit Breaker

“…D IRECT current power distribution is under examination for many applications such as the MVDC power architecture of future naval vessels [1]- [4], and the dc or hybrid ac/dc grid networks with distributed energy resources [5]- [8]. The dc power system architecture has attracted interest as a means for achieving higher overall efficiency for dc loads, enabling easier integration of renewable and distributed energy sources, and providing uninterruptible power with readily available energy storage elements [9]- [11].…”

Hybrid Energy Storage Implementation in DC and AC Power System for Efficiency, Power Quality and Reliability Improvements

“…The probe unit can be a full bridge [180] or half bridge inverter [158] that generates voltage or current with arbitrary amplitude and frequency. It can also be a large capacitor that is connected to a power source via a controlled power switch to form a second-order RLC circuit through the fault path [244].…”

“…It can also be a large capacitor that is connected to a power source via a controlled power switch to form a second-order RLC circuit through the fault path [244]. In these methods, the measured voltage and current are processed by advanced signal processing algorithms, such as fast Fourier transform (FFT) and least square curve fitting to calculate the impedance of the faulted system and estimate the distance from the relay point to fault point [158], [180], [244]. Active distance protection schemes generally do not require a complete shutdown of the microgrid rather, only the affected zone of the system is isolated and tested.…”

“…An advanced protection scheme should have selfdiagnosing and self-healing capabilities to reduce damage caused by short circuit faults and to provide continuous power to loads, even during system faults [112], [156] [158]. The self-diagnosing capability of the system requires a well-designed protection scheme to be able to detect a fault very quickly and accurately locate the faulted area.…”