STABILITY CONTROL MODELLING UNDER DYNAMIC MOTION SCENARIO OF A DIFFERENTIAL DRIVE ROBOT

Intelligence incorporated in many devices makes it easier to achieve self-balancing and autonomous driving in differential drive robot. Basically, differential drive robotic system describes an unstable, nonlinear system related to an inverted pendulum. The research attempts to harness the parameters obtained from a computer-aided design tool (Solid works) to model the system for complete stability control and dynamic motion of the system within a planned trajectory. A linearized dynamic equation is obtained for the overall system design of a mobile robot, and the linear quadratic regulator concept is adopted to obtain an optimum state feedback gain. The simulation results are obtained on MATLAB software interfaced with an Arduino board with deployable sensor technologies. Scenarios of disturbance would be simulated to ascertain the stability conditions of the system at static position or dynamic position. Signal analysis and computer vision techniques serve as leverage to make the design achievable. Localization and navigation referred to as tracking a planned trajectory or moving through paths filled with obstacles in a given space are also included

Enhancing Nigeria’s power grid performance through a hybrid transmission network

The Nigerian power demand is increasing and the existing power grid has proved over-time to be ineffective in meeting up with the increase. The transmission losses experienced on the grid account for a greater part of its problem. The hybrid setting (that is, integrating High Voltage Direct Current (HVDC) transmission lines) was proposed in this work. In the hybrid system, six existing transmission lines representing twenty-nine per cent (29%) of the total lengths of the transmission lines on the existing grid were converted to HVDC lines. Converter stations were introduced at the sending and receiving ends of the lines in the hybrid model. The modelling and simulation of the existing grid was done on Matlab/Simulink while that of the hybrid system was also carried out. The load flow results showed the voltage and load consumption profiles. The total loss on the existing network was 438.1MW while that of the hybrid just added up to 104 MW, the efficiency recorded were 91% and 97% respectively. The results presented the hybrid setting as a better option as improved voltage level was experienced and the losses were drastically reduced.Keywords: Grid, High Voltage Direct Current, Hybrid, Simulink, Transmission losse

Impact of HVDC on the reliability of the Nigerian transmission grid

Regular and reliable access to energy is critical to the foundations of a stable and growing economy. The Nigerian transmission network generates more electricity than is consumed but, due to unpredicted outages, customers are often left without electrical power for several hours during the year. This paper aims to assess the present reliability indices of the Nigerian transmission network, and to determine the impact of HVDCs on system reliability. In the first part of this paper, the reliability of the Nigerian transmission system is quantified by building a model in DIgSILENT PowerFactory and carrying out a reliability study based on data provided by the Nigerian transmission-system operator. Both network indices and load-point indices are evaluated, and the weakest points in the network are identified. In the second part of the paper, an HVDC model is built and integrated into the existing network at the locations identified by the reliability study. A comparative study using two different HVDC connections is then carried out, to determine the critical impact of HVDC on system reliability. The reliability results indicate that the weakest points of the transmission system are the radial feeders, and the highest impact could be achieved by spanning an HVDC line between two busbars located at the two extremes of a radial feeder: Azura and Yola

Temperature Variation Effect on a Rectangular Microstrip Patch Antenna

A novel hypothesis is proposed for the radiation pattern of a Rec-tangular Microstrip Patch Antenna sensitive to temperature variations from the ideal room temperature tolerance under which it was manufactured. In order to validate this hypothetical model, equations relating the resonating frequency, patch length and dielectric constant of the antenna to variations from the room temperature were improved. Simulations were carried out to validate the hypoth-esis in the drifts in ambient temperature effects on dimensions of the patch an-tenna and its field radiation patterns; including its directivity, power pattern, max-imum radiation in the electric-field plane