Modular Z-source DC-DC converter based multilevel power conditioning system for PV applications
In this paper a power conditioning system based on a modular connection of Z-Source DC-DC converters is presented. The proposed structure presents advantages such as modularity, high voltage gain, and multiple independently controlled input terminals. All these make it suitable for application in PV power plants, especially in cases where large arrays are required in which having the ability of independently following the maximum power point of different array sections is desirable. Moreover it is shown that the proposed structure can continue operation even if faulty modules are present in the power conditioner. Theoretical analysis of the operation of Z-Source DC-DC converter is performed and simulations of a 1 [kW] five module power conditioning system presented.
Abstract When Ghubrah MSF Unit no. 2 was commissioned in 1982, it was found that condensate from inter and after condensers was not suitable for boiler feed water as it contains CO2. This study discusses the modification carried out to re-use this condensate by connecting it to the last stage distillate tray box. All other evaporators were modified in the same way after confirming that ammonia and hydrazine levels were within the acceptable limits. This paper also discusses the proposal for modification to direct vent condenser condensate to brine recycle pump suction or last stage flash chamber, in parallel with the existing line to the last stage distillate tray box. Such an arrangement is necessary to avoid contamination of the distillate in case of tube leak in the vent condenser.