Power quality considerations for embedded generation integration in Nigeria: A case study of ogba 33 kV injection substation

The deregulation of the Nigerian power sector has resulted in the quest to explore power generation options for power quality improvement. One of such options is the pattern shift from central power generation to embedded power generation. Network integration of embedded generators (EGs) causes several regulatory, technical and economic issues. This research focuses on power quality challenges that may arise as a result of network integration of embedded generation in a weak electricity networks using Ogba 33 kV injection substation as case study. The embedded generators considered comprised of gas turbine and diesel generators. NEPLAN software was used to perform the load flow analysis with and without EGs connection on the network. This was necessary so as to ascertain the healthiness of the existing distribution network for EGs integration. The power quality issues considered in the study were bus voltage profiles and the total line losses. Simulation results showed that EGs connection improved the voltage profile, for example, bus voltage at PTC 11 kV, improved from 0.881 pu to 0.958 pu while the total active power loss was reduced by 78.16%. The results obtained suggest that the grid is healthy enough to accommodate the EGs with no quality issues.

Embedded Generation (EG) optimization planning and EG caused disturbances.

The objective of this study is twofold. First, it reviews and discusses the optimization of EmbeddedGeneration rapid cycles of industrialization and population growth have contributed to a rise inenergy use. Small areas and poor development in network growth have also contributed to highload densities in areas. This can contribute to problems of power quality and reliability of voltage.In future electrical systems, thus, embedded output is expected to play a growing role.The incorporation of embedded output in a distribution system would increase network efficiencyin terms of increased voltage profile, decrease in line losses and enhanced power quality if properlydesigned. This will reduce the pressure from the grid so that the feeders linking the network to thegrid could be improved. The optimum delivery means that current assets are better used and thecost-effectiveness of the EG penetration is improved. Capacity generation through the busesshould be delegated so that no technological limits are violated and capacity maximized.The Objective Function (OF) is to be maximized according to the constraints. The constraints areThermal Restriction, Transformer Capacity: (The amount of generation attached minus thesummer valley load does not surpass the rating of the transformer at the higher voltage. Therelation between induction generator and high impedance circuitry can also lead to voltageinstability issues if SCR is not held under reasonable constraints (the amount of generator attachedminus the summer valley load does not surpass that of the transformer at the high voltage). In orderto address system planning, operation and pricing, we are evaluating and addressing severaltraditional optimization approaches, including gradient methods, linear programming, quadraticand dynamic programming.The second objective of this study was to discuss the main disturbances caused by EG. We findand discuss that there exist some disturbances. First, the transients. This is due to the significantcurrent shifts when the turbines are attached or disconnected. The second disturbance we areconcerned about is the difference in voltage. This is due to the cyclical change in the output powerof the engine. The third disturbance we have discussed is the interference in the waveform that iscaused primarily by the transmitters linking the generators to the distribution network. Again, the long-duration difference in voltage induced by changes in active and reactive power generators isanother disruption. In addition, as another disturbance, generators may affect backgroundwaveform disruptions in another manner, directly connected with the distribution system.

Embedded Generation Using Shared Solar

The socio-economic development of a country (especially a developing one) is inextricably linked with the availability and affordability of electricity in that country. However most African countries have failed to bridge the gap between the demand and supply of electricity in their country owing either to the non-availability of power or the lack of synergy between the various disciplines that make up the power sector. Bedevilled with the current Covid-19 pandemic which ushers in the digital era of E-learning and virtual trade activities, Africa cannot afford to lag behind as a result of poor electricity supply. Our case study in this paper will be Africa’s most populous country; Nigeria. We would look at the aged long practice of a centralized system of energy production which generates and transmits electricity over long distances (thereby incurring colossal losses), the limitations of the National grid which covers only some parts of the country, the legal constraints, the resort to self-help by Nigerians who seek to produce their own electricity using generators that emit GHG which pollute the atmosphere and the economic implication of running generators, while proffering an eco-friendly solution in distributed or dispersed generation using Shared Solar Energy aimed at resolving the disparity between the demand and supply of Electricity. A solution which will invariably unlock economic growth especially during this Covid-19 pandemic.

A Practical Approach to Optimising Distribution Transformer Tap Settings

This paper proposes a method of determining the optimal tap settings for no-load distribution transformers with tap-changing capabilities that is practical to apply in real distribution networks. The risk of low voltage distribution networks violating voltage constraints is impacted by the increasing uptake of distributed energy resources and embedded generation. Some of this risk can be alleviated by suitably setting no-load transformer tap settings, however, modifying these taps requires customer outages and must be infrequent. Hence, loading over the entire year must be considered to account for seasonal variations when setting these taps optimally. These settings are determined using evolution strategy optimisation based on an average loading case. Monte Carlo simulations are used to calculate the probability that the terminal voltages on the distribution transformer secondary terminals violate the network voltage limits when the optimal set of taps for the average case is applied over a whole year. This algorithm was tested on several cases of a real distribution feeder of varying complexity, and produces a sufficiently-optimal set of taps without significant computation time.

ETAP Based Power System Analysis of a 6 MW Biomass Power Plant

To meet needs of electricity in rural India, there is an alternative option to be searched as the traditional ways and present approach which is renewable energy based and decentralized. While considering for options in the renewable energy sector for this purpose, such as bio-energy technologies are being explored. This work basically is intended to minimize the problems and difficulties involved in the generation of power by biomass combustion technique. The work behind this paper is to conduct a power system analysis of a 6 MW biomass power plant to calculate an impinging force advantageously placed distributed or embedded generation on distribution systems using an iterative power system simulation tools as regards the load flows, short circuit or fault studies, relative protective relay co-ordinations. This paper is based on modeling of single line diagram and simulates it through Electrical Transient Analyzer Program (ETAP) software. This work is investigated and resolved the problem to build the required confidence that a high penetration of biomass power plant connected to the grid is both realistic and secure.

A review of high frequency emission in 2-150 kHz range

This paper reviews state-of part of discussion that concern about high frequency emission. Sometimes there may be emission in the range of high frequencies because of the fast improvement of energy saving equipments in our homes. Investigators and standardized organization given a very much importance to the disturbances of power quality that occur in the range middle of 2-150 kHz. Disturbances of these high frequencies are becoming an increasing concern in the industry, particularly due to the growth of distributed and embedded generation. Now days, a large number of researches are proceeding at a large number of places, yet information regarding supraharmonics remains confined.