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Decades after the invention of the Cockcroft–Walton voltage multiplier, it is still being used in broad range of high voltage and ac to dc applications. High voltage ratio and high efficiency are its main features. Due to the limitations of original circuit, reducing the output ripple and increasing the accessible voltage level motivated scientists to propose new topologies. However, over the worldwide bibliography, most of Cockcroft-Walton voltage designers persist in using equal capacitances in every stage without considering an optimal design. The aim of this paper is to do a comparative study of the design and simulation of a fixed model (conventional model used by most authors) and a variable model (new design) of generating High Voltage Direct Current (HVDC) based on Cockcroft–Walton voltage multiplier that stresses on the choice of the adequate capacitance values to reduce the output voltage drop, produce less ripple and the calculations of the optimal number of stages that is necessary to produce the desired output voltage with a better performance. The generation of HVDC based on Cockcroft–Walton voltage multiplier and an eight stage was used for simulations and theoretical analysis which yielded up to 4.4 kV DC from an input voltage of 230 V, 50 Hz ac supply. The results are compiled from the simulations done on MATLAB/SIMULINK, by the designs and simulations characteristics of the models the performances, output voltages and ripple voltages per stage have been compared.

The traditional electric grid of the City of Kumba has been experiencing a constant failure which leads inhabitant to experience constant blackout. This constant blackout persists and stays for a long time due to the lack of communication between equipment, consumer and supplier. Whenever there is a fault, the repairing agents walk along the feeder to find the fault. This manual fault finding increases the restauration time which leads to the augmentation of the blackout period. Factors responsible for the failure of the line are complex to be controlled. It is necessary to reduce restauration time by introducing Information and Communication Technologies (ICT) and sensing system in the grid and making it to be smart. ICT in this smart grid, sensors and smart meters are meant to assure two-way communication between the supplier and the consumer. They send real time information which is computed at the control center to optimize the entire grid. Distributed generation is also introduced in the system for two purposes. To complete the lag in power demand of the grid and to take over the supply when the main feeder is faulty. Various distributed generation sources studied led to the choice of solar power plants thanks to their low production of Greenhouse Gas (GHG) and availability of their resources in the city. A model has been proposed for the distributed generation and optimization of the smart grid. The system indexes obtained without distributed generation in the grid are different from that with. The difference in these indexes proved that the grid has been optimized. However, the reliability of the grid is enhanced after the introduction of distributed generation into the system. This enhancement in reliability declares that with distributed generation into the grid, the population of Kumba has a reliable power supply, which makes them to have energy throughout.

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