Methodology of Automated Protection Analysis for Large Distribution Feeders With High Penetration of Photovoltaic Systems

Abstract

This paper presents highly automated methods to study the protective device coordination in large distribution systems with high penetration of distributed photovoltaic (PV) generation. A real distribution feeder with large-scale distributed PV generation has been modeled and verified using the analysis tool OpenDSS and utilizing extensive field measurements. With the accurate and validated feeder model, thorough protection coordination of the system is investigated by applying all the possible phase and ground faults under various scenarios. Under varying PV penetration levels and with different PV interface transformer connections, settings for the phase and ground relay and recloser are verified/defined such that proper coordination is achieved for the entire feeder under all operating conditions, corresponding to both fuse-clearing and fuse-saving schemes. An optimization-based design of protective devices is introduced that ensures proper protection coordination under thousands of possible fault cases. The automated protection analysis has been implemented using OpenDSS with MATLAB COM interface, and this approach and tools can be extended to analyze and design protection coordination of any large distribution feeder, as well as to use as a screening tool while evaluating large scale PV on distribution feeders.

Synthetic Harmonic Distance Relaying for Inverter-Based Islanded Microgrids

“…Current magnitude-based methods such as overcurrent relays, reclosers, and fuses can either fail to detect faults (i.e., compromised sensitivity), or encounter loss of coordination between primary and backup pairs of protection devices (i.e., compromised selectivity) [1]. Therefore, protection coordination solutions in [4], [5] are not applicable in a microgrid context. Additionally, impaired fault current/voltage phase angles result in malfunction of existing commercial torque-and impedance-based directional elements [3].…”

A novel adaptive protection coordination scheme for radial distribution networks in the presence of distributed generation

“…Another classification of protection coordination methods of active distribution systems is presented in Table 1. According to Table 1, both DG‐based and the protection system (PS)‐based strategies can be implemented in an offline 15,22‐24 or online 8,25‐30 manner. In the offline methods, the coordination of protection devices is ensured in sizing and siting of DGs in the planning stage 6,31‐33 or output of DGs in operation stage 8,34‐36 .…”

“…Furthermore, the offline coordination of protection system can only consider a limited number of distribution system states. On the other hand, online protection coordination can be realized by adaptive protection setting, 26,37,38 group setting, 39‐41 telecommunication between protection devices, 26,42 and using multi‐agent‐based 13,28,43‐45 coordination methods. In some online methods, 46‐50 the optimal setting of protection devices can be determined for each change in the topology of the network or DG output.…”

“…Some other online methods are communication‐based which can provide remote protection coordination or simultaneously coordinate DGs output and relays settings. However, the reliability and speed of these methods are dependent on the performance of the communication system 26,28 …”

Modelo resiliente de redes de distribución considerando flujos de potencia basado en teoría de grafos

“…Por lo tanto, una infraestructura de energía que pueda mantener altos niveles de rendimiento en cualquier condición debe ser confiable para los cortes de energía más comunes, pero también resistente a desastres mucho menos frecuentes. Por su sensibilidad ante eventos extremos, las redes de distribución aéreas presentan un nivel de resiliencia más bajo que su homólogo redes de distribución subterráneas [5], siendo estas una alternativa apropiada para zonas urbanas en las cuales los consumidores presentan un crecimiento ordenado y su dispersión geográfica no es alta, a diferencia de las zonas rurales que presentan un alto nivel de dispersión geográfica, en la que generar un enrutamiento de tendido de cable se torna en extremo complejo [6], [7]. Para tener una visión global de los sistemas de distribución, ya sean estos aéreos o subterráneos, antes, durante y después de un evento catastrófico, es pertinente el estudio de los flujos de potencia, utilizados para resolver las condiciones de funcionamiento en estado estacionario [8].…”