The thermal analysis of radiant heating by the final elements method to choose suitable control for central heating systems in host buildings

This research performs thermal analysis of the central heating's radiator by the final elements method manner using Cosmos/m2.6, Where it was designing a three dimensional model of the radiator with engineering specifications that mimic one of the used radiators .Then apply a convection simulates the role of the mediator heating used and ambient temperature for concluding the mathematical behavior of thermal gradient within the radiator. Research proposing a control system depends on adjusting the intermediary of heating inside the radiator, through the installation of flow control valve which works by D.C motors at the entrance to each radiant. The research shows the inability of depending on controlling system which uses the PI controller in building a suitable control system, Because the difficulty of receiving signals from analog temperature sensor that reflect the constant readings of room temperature which makes the response of control valve for signals slow, Thus makes the use of PI unhelpful of the economic and technical side.

Enhancement of voltage Stability in power transmission networks using Static Compensator (STATCOM( based on Fuzzy logic

The fluctuation of voltage cannot be tolerant for equipment in modern industrial plants such as lighting loads, PLC, robots, and another equipment, which exist in transmission and distribution systems, so we should use proper aids to regulate voltage and control it. In this study a (± 25Mvar) Static Synchronous Compensator (STATCOM) is used to enhance voltage stability in a (66 kv, 1500MV.A) power transmission network. The STATCOM in this study regulates the voltage of the transmission network for changing in voltage (± 7%) from the nominal value. A model of the power transmission system and another model of the STATCOM device, which will enhance the stability of voltage are designed in MATLAB/Simulink. And the control of (STATCOM) is achieved by using a Proportional Integrative (PI) controller with Fuzzy Logic Supervisor to adjust the parameters in PI controller in DC voltage regulator during transient states of load changing which gives more stability in DC voltage. The results of the simulation are shown. This study demonstrates the ability of STATCOM for regulating the voltage of the transmission system by injecting and absorbing reactive power from the power system, and the DC voltage be more stability by using Fuzzy Logic supervisor.