Automatic Optimization of Gas Insulated Components Based on the Streamer Inception Criterion

Gas insulated transmission lines (GILs) are used in electrical systems mainly for power transmission and High Voltage substation interconnection. In this paper, we focus on the development of complex numerical tools for the optimization of gas insulated HVDC components by the estimation of realistic electric field distribution and the voltage holding of the designed geometry. In particular, the paper aims at describing the correct modelling approach suitable to study high voltage components in DC, considering the nonlinear behaviour characterizing the electrical conductivity of solid and gas insulators. The simulated field distribution is then adopted to estimate the voltage holding of the dielectric gas, with a convenient engineering technique, based on the streamer criterion. These two tools are integrated in an automatic optimization package developed in COMSOL® and MATLAB®, with the purpose of adjusting the critical geometry features, suffering from excessive electrical stress and possibly giving rise to electrical breakdown, in order to guide the designer towards a robust solution.

A New Approach for Automatic Optimization of Complex Fracture Network in Shale Reservoirs

Shale gas reservoirs have gradually become the main source for oil and gas production. The automatic optimization technology of complex fracture network in fractured horizontal wells is the key technology to realize the efficient development of shale gas reservoirs. In this paper, based on the flow model of shale gas reservoirs, the porosity/permeability of the matrix system and natural fracture system is characterized. The fracture network morphology is finely characterized by the fracture network expansion calculation method, and the flow model was proposed and solved. On this basis, the influence of matrix permeability, matrix porosity, fracture permeability, fracture porosity, and fracture length on the production of shale gas reservoirs is studied. The optimal design of fracture length and fracture location was carried, and the automatic optimization method of complex fracture network parameters based on simultaneous perturbation stochastic approximation (SPSA) was proposed. The method was applied in a shale gas reservoir, and the results showed that the proposed automatic optimization method of the complex fracture network in shale gas reservoirs can automatically optimize the parameters such as fracture location and fracture length and obtain the optimal fracture network distribution matching with geological conditions.

Investigation of the possibility of regulation and automatic optimization of the control system of a chamber grain dryer

The regulation of the coolant speed during convective drying in a stationary grain layer allows the maximum use of the amount of heat energy for drying the material. The paper presents the results of a study of the regulation of the coolant speed on an experimental drying plant for use in the automatic control system of a chamber grain dryer. The article also discusses the issues of energy saving efficiency in drying chambers. The possibility of automatic control of the main parameters control system using a microcontroller is analyzed. Keywords: DRYING MODES, DRYING ZONE, AUTOMATIC CONTROL, TEMPERATURE CONTROLLER, FAN, OPTIMIZATION, MICROCONTROLLER, FREQUENCY CONVERTER