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1. TRANSIENT BIOBATTERIES: MICROFLUIDIC CONTROL FOR PROGRAMMABLE DISSOLUTION

   Mohammadifar, M.; Choi, S. (June 2018, Technical digest SolidState Sensor Actuator and Microsystems Workshop)

   We report a simple approach to develop transient microbial fuel cells with the capability of dissolving in water after stable power generation within a programmed period. This novel water-soluble biobattery makes use of the integration of a dissolvable paper-based substrate, a simple pencil-drawn graphite anode, and a Prussian-blue (PB) cathode. The device features (i) a low cost transient paper-based platform, (ii) easily accessible electrode materials and simple fabrication steps and (iii) a time-controlled operation by using the number of serpentine microfluidic channels. The biobatteries reached to a maximum power of 0.5μW and a current 15.6μA and achieved full dissolution in less than 60 minutes. 

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2. Probabilistic Transient Stability Assessment of Power System Considering Wind Power Uncertainties and Correlations

   Yue, Ziyuan; Liu, Yanli; Yu, Yixin; Zhao, Junbo (January 2020, International journal of power energy systems)

   This paper proposes a simple yet effective method for power system probabilistic transient stability assessment considering the wind farm uncertainties and correlations. Specifically, the inverse Nataf-transformation-based three-point estimation method and the Cornish-Fisher expansion have been integrated together to deal with the uncertainties and the correlations among different wind farms. Then, by resorting to the extended dynamic security region approach, the transient stability criterion is derived as a linear combination of nodal injection vector under a given fault condition. New indices for the identification of critical lines have also been developed. Extensive simulation results carried out on four different systems, including the practical GZ power system in China show that the computational efficiency of the proposed method is much higher than the Monte-Carlo-based method and other methods almost without the loss of accuracy. The effectiveness of the proposed method under different penetrations of wind power with different degree of correlations is also validated. It is shown that correlation among wind farms has a larger impact on the transient stability results with a higher penetration level of renewable energy. 

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3. Transient behaviour verification and controller tuning for an uncertain grid‐connected photovoltaic system using reachability analysis

   https://doi.org/10.1049/rpg2.12212  

   Shabestari, Parisa_M; Mehrizi‐Sani, Ali (May 2021, IET Renewable Power Generation)

   Abstract Power electronics–based converters for photovoltaic (PV) systems are susceptible to overcurrents; it is important to design their controllers to reduce the transient current for all viable operating conditions. To design a current controller and find the maximum transient current via simulation‐based techniques, the exact values of the system parameters, initial states, and inputs are required. However, they are not precisely known in practice, some system parameters such as inductances may change over time, and output power and load are variable. The uncertainty in the parameter (filter inductance) and input of the system (injected power) should be considered in the analysis of a PV system controllers as it can degrade their performance, which are designed for the system nominal parameters. This paper employs reachability analysis for a grid‐connected PV system to (1) find the maximum transient current, (2) devise an improved PI current controller and (3) compare the maximum transient current in PI‐ and internal model control (IMC)‐based controllers with uncertain‐but‐bounded input power and inductance error. Simulation and experimental studies showcase the results. 

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4. A Transient Spore‐Forming Microbial Fuel Cell with Extracellularly Biosynthesized Tin Oxide Nanoparticles for Powering Disposable and Green Papertronics

   https://doi.org/10.1002/adsu.202300357  

   Rezaie, Maryam; Rafiee, Zahra; Choi, Seokheun (October 2023, Advanced Sustainable Systems)

   Abstract Transient electronics, which can operate only for short‐lived applications and then be eco‐friendly disintegrated, create opportunities in environmental sensing, healthcare, and hardware security. Paper‐based electronics, or papertronics, recently have rapidly advanced the physically transient device platform because paper as a foundation offers an environmentally sustainable and cost‐effective option for those increasingly pervasive and fast‐updated single‐use applications. Paper‐based power supplies are indispensable to realize a fully papertronic paradigm and are a critical enabler of environmentally benign power solutions. Microbial fuel cells (MFCs) hold great potential as power sources for such green papertronic applications. This work reports the design, operation, and optimization of a high‐power papertronic MFC by biosynthesizing microbe‐mediated tin oxide nanoparticles (SnO₂NPs) on dormant Bacillus subtilis endospores. They form an electrical conduit that improves electron harvesting during the spore germination and power generation. The MFC is packaged in a sub‐microporous alginate to minimize the potential risk of bacteria leakage. Upon the introduction of water, the paper‐based MFC generates a significantly enhanced power density of 140 µW cm⁻², which is more than two orders of magnitude greater than their previously reported counterparts. Six MFCs connected in series generate more than sufficient power to run an on‐chip, light‐emitting diode. 

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5. Efficient Simulation of Cascading Outages Using an Energy Function-Embedded Quasi-Steady-State Model

   https://doi.org/10.1109/TPWRS.2025.3527811  

   Guo, Zhenping; Su, Xiaowen; Huang, Kaiyang; Sun, Kai; Simunovic, Srdjan; Chiang, Hsiao-Dong (January 2025, IEEE Transactions on Power Systems)

   This paper proposed an energy function-embedded quasi-steady-state model for efficient simulation of cascading outages on a power grid while addressing transient stability concerns. Compared to quasi-steady-state models, the proposed model incorporates short-term dynamic simulation and an energy function method to efficiently evaluate the transient stability of a power grid together with outage propagation without transient stability simulation. Cascading outage simulation using the proposed model conducts three steps for each disturbance such as a line outage. First, it performs time-domain simulation for a short term to obtain a post-disturbance trajectory. Second, along the trajectory, the system state with the local maximum potential energy is found and used as the initial point to search for a relevant unstable equilibrium by Newton's method. Third, the transient energy margin is estimated based on this unstable equilibrium to predict an out-of-step condition with generators. The proposed energy function-embedded quasi-steady-state model is tested in terms of its accuracy and time performance on an NPCC 140-bus power system and compared to a quasi-steady-state model embedding transient stability simulation. 

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