This paper reviews the research trends in probabilistic power flow (PPF) calculation methods, which have become increasingly important in modern power systems facing uncertainty from renewable energy integration, demand fluctuations, and other stochastic influences. The paper categorizes PPF techniques into two main groups: approximate methods and simulation-based methods, and provides an overview of specific techniques.

A method for estimating the internal pressure rise when ground fault occur inside power cable terminations has not been established yet because the pressure rise due to a ground fault is a fast phenomenon that occur within a few milliseconds. In this study, a mock-up experiment was conducted in order to reproduce the first peak of the pressure rise when a ground fault occurs, by burning explosives in the insulators used in 110kV class cable terminations. The experimental results were compared with numerical analysis result, which was solved by the equation of state considering the generation of shock waves. The maximum pressure at the mock-up experiment was 11.4MPa at 2.2ms. Compared to a numerical result with an initial pressure of 10MPa in the combustion gas region, the maximum pressure of the numerical analysis was 25% higher and the time was 0.27ms faster than the result of the mock-up experiment. The local pressure rise could be reproduced approximately by this analysis method. If the strain of the sample and fluid leakage could be reproduced in the model, more accurate analytical results could be obtained.

A linear equation derived from the swing model of synchronous generator without including K-coefficient of maximum transmission power is introduced for the evaluation of inertia and damping terms of the inverter. The evaluation methods and results with two types of utility frequency change conditions; linear and 2^nd polynomial-frequency change, observing inverter output port frequency, ROCOF and active power are reported. The evaluation results show sufficient explanation of inverter power response with accuracy against the utility frequency change.

Stator windings of hydro generators are exposed to combined thermal, voltage, environmental, and mechanical stresses, which deteriorate the insulation performance. On the other hand, various stator faults occur in the stator. The stator faults are accompanied by partial discharges, which may lead to dielectric breakdown depending on the type of faults. This paper presents a case study of detecting stator faults by on-line partial-discharge diagnostics. The type of stator faults is identified based on reproducible experiments. Furthermore, the advantages of online partial-discharge diagnostics compared with offline diagnostic methods in detecting stator windings are discussed.

Taking reuse batteries into consideration, we revealed each load of 2 parallel-connected cells with different performances. As simulation models, 2 types of imaginary cells with either degradation of capacity or internal resistance were prepared in addition to a new cell in order to verify their influences separately. The result indicates that contrary to previous views, the load of the cell with degraded performance is not always smaller in terms of following evaluation items: (1) current expressed as hour rate based on actual capacity and (2) state of charge.