The Exploration of Capacitive Effects of XLPE Cables in Medium Voltage Distribution Systems

Öz

Cross-linked polyethylene insulation (XLPE) type underground power cables used in medium and low voltage distribution systems bring out a reactive effect with capacitive character due to the constructional properties of XLPE cables. If this effect is not eliminated, it causes negative influences on losses, cost, and capacity. Therefore, this study focuses on the capacitive effects of XLPE type underground cables and the appropriate compensation systems to overcome the issue on a medium voltage distribution system with 5500 m-length. The measurements taken from a medium voltage substation have been compared to corresponding simulation results. As a result, a very successful match between simulation and measurements has been achieved. Furthermore, a series of suggestions for establishing appropriate compensation has been presented, which is expected to serve the more efficient transmission and distribution of energy. Since the need for more energy and the amount of utilization are increasing, it is compulsory to carry out the works to decrease the loss rate of the transmission and distribution of energy.

Anahtar Kelimeler

• XLPE type cables
• compensation
• capacitive effect
• shunt reactor
• MV distribution network

XLPE Kabloların Orta Gerilim Dağıtım Sistemlerinde Kapasitif Etkisinin İncelenmesi

Öz

Orta ve alçak gerilim dağıtım sistemlerinde kullanılan çapraz bağlı polietilen yalıtım (XLPE) tipi yeraltı güç kabloları, yapısal özellikleri nedeniyle kapasitif karakterli reaktif bir etki oluştururlar. Bu etki ortadan kaldırılamazsa, kayıplar, maliyetler, ve kapasite üzerinde olumsuz etki oluşturur. Bu nedenle, bu çalışma 5500 m uzunluğunda bir orta gerilim dağıtım sistemindeki XLPE tipi yeraltı kablolarının kapasitif etkilerine ve bu etkilerin üstesinden gelebilmek için uygun kompanzasyon sistemlerine odaklanmaktadır. Orta gerilim trafo merkezinden alınan ölçümler, simülasyon sonuçlarıyla karşılaştırılmıştır. Sonuç olarak, simülasyon ve ölçümler arasında çok başarılı bir eşleşme sağlanmıştır. Ayrıca, daha verimli enerji iletimi ve dağıtımına hizmet etmesi beklenen uygun kompanzasyonun oluşturulmasına yönelik bir dizi öneri sunulmaktadır. Daha fazla enerji ihtiyacı ve kullanım miktarı arttığı için enerjinin iletim ve dağıtımındaki kayıp oranını azaltacak çalışmaların yapılması gereklidir.

Anahtar Kelimeler

• XLPE kablo
• kompanzasyon
• kapasitif etki
• şönt reaktör
• orta gerilim dağıtım şebekesi

Kaynakça

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