<Development of short-circuit current characteristic maps for AC/DC power systems>
Transient analysis is performed when a DC power supply is connected to an AC system, and a short-circuit current from the AC side flows into the DC side due to a fault in the inverter on the DC side, or a fault occurs on the AC side and a short-circuit current flows from the AC and DC sides.
-Related Papers-
* M.S.S. Danish, M. Iwata, Y. Yokomizu, Naoto Kodama: “Fundamental Analysis of Fault Current in the Case of Short-Circuit on the DC Side of a Hybrid AC/DC System”, Tokai-Section Joint Conference on Electrical, Electronics, Information, and Related Engineering, A4-6, Online, Japan (Aug.2022)
* M. S. S. Danish, M. Iwata, Y. Yokomizu, N. Kodama: “Simplified analysis of short-circuit current for hybrid AC/DC delivery system”, 13th International Workshop on High Voltage Engineering (IWHV 2022), EPP-22-127/SP-22-062/HV-22-108, pp. 83-86, Naha, Japan (Nov. 2022)
<Clarification of current interruption characteristics during voltage and current distortion caused by the introduction of a large number of inverters/converters>
When a DC power supply such as PV is connected to an AC system, harmonics generated in the switching circuit of the inverter on the DC side may flow into the AC system. For example, assuming a case in which the LC filter installed to block harmonics fails, we perform a transient analysis of the distortion of current and voltage waveforms near the current zero point when harmonics flow into the AC system.
-Related Papers-
*Under Construction
<Development of a converter control method for multi-terminal DC transmission systems>
We will develop a converter control method for multi-terminal DC transmission systems, which are expected to be introduced in the future, to efficiently and safely transmit power from offshore wind farms, etc. to multiple points, including a converter control method in emergency situations such as when a fault occurs in the DC section. In addition, we also will develop a tidal current control system with multiple terminals, which takes into account that the operating scheme of the DC transmission system reflects the state of the connected AC system, and conducting simulation analysis to confirm the effectiveness of the system.
-Related Papers-
* Y. Matsuoka, A. Nakamura, M. Iwata, Y. Yokomizu, N. Kodama: “Fundamental study of frequency control considering converter capacity for multi-terminal HVDC system”, Tokai-Section Joint Conference on Electrical, Electronics, Information, and Related Engineering, A3-3, Gifu, Japan (Aug. 2024)
* A. Nakamura, M. Iwata, Y. Yokomizu, N. Kodama: “Fundamental Study on Terminal Coordinated Control Method for MTDC System – Proposal of DC-AVR Terminal Detection Method by DC Voltage Control -”, The 2024 Annual Conference of Power and Energy Society IEE of Japan, No. 125，pp. 2_1_19 – 2_1_20, Osaka, Japan (Sep. 2024)
* A. Nakamura, M. Iwata, Y. Yokomizu, N. Kodama: “Fundamental Study on Control Method Considering Power Sharing Between Positive Pole and Negative Pole of Bipolar MTDC System”, Joint Technical Meeting on “Power Engineering” and “Power Systems Engineering “, IEE Japan, PE-24-171/PSE-24-171, Sendai, Japan (Sep. 2024)