The Unified Power Quality Conditioner Control Method Based on the Equivalent Conductance Signals of the Compensated Load

This paper proposes a new control method for a Unified Power Quality Conditioner (UPQC). This method is based on the load equivalent conductance approach, originally proposed by Fryze. It can be useful not only for compensation for nonactive current and for improving voltage quality, but it also allows one to perform some unconventional functions. This control method can be performed by extending the orthodox notion of ‘static’ load equivalent conductance into a time-variable signal. It may be used to characterize energy changes in the whole UPQC-and-load circuitry. The UPQC can regulate energy flow between all sources and loads being under compensation. They may be located as well for UPQC’s AC-side as DC-side. System works properly even if they switch their activity to work either as loads or generators. The UPQC can operate also as a buffer, which can store/share the in-load generated energy amongst other loads, or it can transmit this energy to the source. Therefore, in addition to performing the UPQC’s conventional compensation tasks, it can also serve as a local energy distribution center.

Effect of Dielectric Constant of Medium on Conductance for Trimethylsulfonium Halides in Normal and Branched Alcohols

The conductance parameters, Λo (equivalent conductance at infinite dilution) and KA (association constant) for trimethylsulfonium halides (Bromide and Iodide) in methanol, ethanol, n-propanol, 2-propanol and n-butanol have been evaluated at 25°C from the conductance measurements. The values of Λo for different salts decrease with decreasing dielectric constant of medium (D) with some variations and are in the order of MeOH > EtOH > n-PrOH > 2-PrOH > n-BuOH. The association constants of the same salts in different alcohols increase with decreasing dielectric constant of medium and are in the order of n-BuOH > 2-PrOH > n-PrOH > EtOH > MeOH.

Improvement of corrosion process control techniques at engineering facilities under high parameters of water coolants

Introduction. The work objective is to increase the reliability of the prediction methods for the lithium hydroxide behavior in the steam-water circuit at the thermal power plants and nuclear power plants, and for the operational monitoring of the pH index of steam solutions. A method of operational control is developed on the basis of the conductometric measurements of the hydrogen index of the corrosion inhibitor vapor solutions for construction materials of lithium hydroxide used at the TPP and NPS.Materials and Methods. A mathematical model method is used for the practical implementation of the high-temperature operational control of the steam solution pH index.Research Results. A method for monitoring the pH of vapor solutions of lithium hydroxide based on the determination of vapor concentration through the steam condensation in the coolable conductivity sensor located in the vapor space of the steam generator is developed. This has significantly improved the accuracy of determining the lithium hydroxide concentration. Equations describing the change in the limiting molar equivalent conductance and dissociation constants of lithium hydroxide in a wide range of state change parameters are proposed.Discussion and Conclusions. The proposed on-line technique of testing the pH value of steam solutions, and mathematical models for calculating the limiting molar equivalent conductance and dissociation constants provide an acceptable error level calculations and the capability of measurements automation. With an increase in the vapor temperature up to 573.15 K, the necessity arises to fortify lithium hydroxide in the vapor to 10-2 mol/kg.