Electronic Theses and Dissertation

Pertumbuhan kendaraan listrik (Electric Vehicle / EV) mendorong peningkatan jumlah Stasiun Pengisian Kendaraan Listrik Umum (SPKLU), khususnya tipe DC fast charging berdaya besar. SPKLU menggunakan konverter daya berbasis elektronika daya yang bersifat nonlinier sehingga berpotensi menimbulkan distorsi harmonisa arus pada sistem distribusi. Dalam praktik, evaluasi harmonisa SPKLU masih sering berfokus pada nilai Total Harmonic Distortion of current (THDi), padahal standar IEEE Std 519-2014 menetapkan batas harmonisa arus berdasarkan parameter Total Demand Distortion (TDD) yang dievaluasi pada Point of Common Coupling (PCC). Penelitian ini bertujuan menganalisis karakteristik harmonisa arus SPKLU DC fast charging berdaya 120 kW serta mengevaluasi kepatuhannya terhadap IEEE 519-2014 menggunakan parameter TDD. Analisis dilakukan berdasarkan data pengukuran aktual pada satu unit SPKLU yang beroperasi pada kondisi pengisian baterai kendaraan listrik dengan State of Charge (SOC) 50–70% yang merepresentasikan fase constant current. Sistem distribusi yang dianalisis menggunakan transformator 630 kVA dengan impedansi 4%. Perhitungan TDD menggunakan arus beban maksimum aktual pada PCC sebagai arus referensi (IL). Selanjutnya dilakukan limit study untuk memproyeksikan pengaruh penambahan jumlah SPKLU terhadap nilai TDD sistem menggunakan pendekatan batas atas (worst-case). Hasil penelitian menunjukkan bahwa satu unit SPKLU menghasilkan nilai THDi sebesar 5,5% dan nilai TDD sebesar 5,5%, yang masih berada di bawah batas IEEE 519-2014. Hasil limit study menunjukkan bahwa kapasitas transformator menjadi faktor pembatas utama untuk penambahan beban. Ketika ditambahkan SPKLU 120 kW hingga berjumlah 3 unit pembebanan transformator menjadi 67%.

The growing adoption of electric vehicles (EVs) has led to a rapid increase in the deployment of Electric Vehicle Supply Equipment (EVSE), particularly high-power DC fast-charging stations. DC fast chargers employ power-electronic converters that exhibit nonlinear characteristics, which may introduce current harmonic distortion into distribution systems. In practice, harmonic evaluations of EV fast chargers are often based on the Total Harmonic Distortion of current (THDi). However, IEEE Std 519-2014 specifies current harmonic limits in terms of Total Demand Distortion (TDD), which is evaluated at the Point of Common Coupling (PCC). This study aims to analyze the current harmonic characteristics of a 120 kW DC fast charger and to assess its compliance with IEEE Std 519-2014 using the TDD parameter. The analysis is based on field measurement data obtained from a single fast-charging unit operating during an EV charging process within a State of Charge (SOC) range of 50–70%, which represents the constant-current charging phase. The analyzed distribution system is supplied by a 630 kVA transformer with an impedance of 4%. The TDD is calculated using the measured maximum load current at the PCC as the reference current (IL). Furthermore, a limit study is conducted to project the impact of increasing the number of fast chargers on the system TDD using a worst-case upper-bound approach. The results show that a single DC fast charger produces a THDi of 5.5% and a TDD of 5.5%, both of which remain below the limits specified in IEEE Std 519-2014. Based on the limit study, transformer capacity is identified as the dominant limiting factor for additional load integration. The connection of three 120 kW fast-charging units results in a transformer loading level of 67%.