https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/161 2026-07-24T08:08:48Z 2026-07-24T08:08:48Z Park, Su-Seong Jung, Jin-Woo Kim, Rae-Young Lee, Dong-Geun https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/212473 2026-04-30T07:00:08Z 2026-09-01T00:00:00Z

Title: Distributed DC voltage based grid forming control of interlinking converters in DC local grids Authors: Park, Su-Seong; Jung, Jin-Woo; Kim, Rae-Young; Lee, Dong-Geun Abstract: This paper proposes a distributed DC-voltage-based grid-forming control strategy for bidirectional interlinking converters in DC local grids. The proposed method establishes GFM (grid-forming) capability through DC-voltage synchronization among converters and enables sensorless droop operation using AC active power feedback. Small-signal analysis reveals the synchronous oscillation mechanism, which is mitigated using a notch-filterbased stabilization method. Simulation results demonstrate that the proposed control effectively suppresses synchronous oscillation and improves dynamic performance compared with conventional droop-GFM and DVSCGFM methods under various scenarios including weak-grid and increased renewable penetration conditions.

2026-09-01T00:00:00Z Lee, Sung-Min https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/213885 2026-06-22T01:30:39Z 2026-09-01T00:00:00Z

Title: Selective radiation emitters consisting of black silicon and photonic crystal for thermophotovoltaic systems Authors: Lee, Sung-Min Abstract: Highly radiative, wavelength-selective emitters are investigated for efficient Thermophotovoltaic (TPV) systems by integrating black silicon with a high-temperature one-dimensional photonic crystal (1D PC). The black silicon featuring a randomly distributed nanocolumn surface serves as an ideal black body emitter with high emissivity, while the 1D PC composed of alternating metal and dielectric layers provides spectral radiation selectivity and hence effectively suppresses radiation loss. Experimental results for 1D PC-integrated black silicon, fabricated using a scalable and potentially cost-effective method, show a two-fold improvement in spectral cut-off efficiency compared to pure black silicon. The robust operation under high-temperature conditions demonstrates its potential as a feasible emitter. Details of the design process, fabrication strategy, and quantitative characterization suggest the promising potential of combining ideal black silicon emitters with spectrally manageable photonic technology to advance TPV systems.

2026-09-01T00:00:00Z Seo, Beom-Jun Jung, Jiwon Choi, Jae-Hoon Ahn, Se-Hun Kim, Nayeon Chung, Chin-Wook https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/218607 2026-07-09T02:00:15Z 2026-07-01T00:00:00Z

Title: Noninvasive method for monitoring plasma parameters and dielectric thickness applicable to plasma processing Authors: Seo, Beom-Jun; Jung, Jiwon; Choi, Jae-Hoon; Ahn, Se-Hun; Kim, Nayeon; Chung, Chin-Wook Abstract: Maintaining process uniformity is critical in high-aspect-ratio etching, where local plasma and surface conditions strongly influence etch performance. Among the hardware components affecting uniformity, the focus ring, a dielectric structure surrounding the wafer, plays a key role in shaping the edge plasma and maintaining uniform ion flux. However, its gradual erosion during operation causes nonuniform etch profiles, particle generation, and yield degradation, making real-time wear monitoring essential for stable, high-yield semiconductor processing. Here, we present an electrical sensing method for real-time, in situ monitoring of thick dielectric components under plasma operation. The plasma–dielectric system is modeled as an equivalent circuit, and dielectric thickness is extracted from capacitance using a dual-frequency method that decouples plasma effects. Fringing effects are incorporated into the ideal parallel-plate capacitor model using a Padé approximant, and the model is further refined by weighted least-squares fitting. The proposed method enables accurate thickness measurement despite plasma variations and provides a practical, noninvasive approach for monitoring both plasma parameters and focus ring wear during plasma processing.

2026-07-01T00:00:00Z Park, Su-Seong Lee, Dong-Geun Kim, Rae-Young https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/211912 2026-04-02T06:30:26Z 2026-06-01T00:00:00Z

Title: Development of E-STATCOM analytical model for impact analysis of the southwest sea offshore wind farm linked system Authors: Park, Su-Seong; Lee, Dong-Geun; Kim, Rae-Young Abstract: An electromagnetic transient (EMT) analysis model is presented to evaluate the impact of large-scale offshore wind farm integration on the power system in the southwestern sea of Korea, in accordance with the 10th Basic Plan for Power Supply and Demand. An efficient E-STATCOM analysis model is developed by incorporating average representations of the MMC, DC–DC converter, and energy storage system (ESS) into an EMT framework, enabling system-level dynamic analysis with reduced computational burden while preserving essential transient behavior. Model parameters are derived based on power system characteristics and STATCOM ratings. The southwestern regional transmission system is converted into an EMT environment, and the operation and control modes of the proposed E-STATCOM are verified. The proposed model is comparatively evaluated against conventional EMT modeling approaches to assess dynamic fidelity and computational efficiency. The impact of E-STATCOM integration is analyzed mainly from voltage and frequency perspectives, considering variations in transmission lines, load conditions, and power generation before and after connection. The results confirm that the proposed EMT modeling framework provides an effective and scalable solution for analyzing large-scale offshore wind integration under weak-grid conditions. © 2026 The Authors.

2026-06-01T00:00:00Z