Today, energy is a vital component in the functioning of a hospital. Hospital technical facilities have several types of technologies, these include appliances for use; examination apparatus. So, for Quality Health Care in a hospital, there is a need to ensure the proper functioning of hospital equipment. In addition to the required maintenance as specified by the device manufacturer, the quality of the electrical energy across the device must be ensured. This article is an analysis of the quality of electric energy at the substation of National Hospital of Niamey. Thereby, the data collection, followed by the data processing and analysis revealed the parameters characterizing the quality of electrical energy across the substation. Our studies have shown that the substation is underutilized as the maximum inrush current is less than half the available current. The current was consumed by the three phases has resulted in a strong current unbalance (230 A). However, the current unbalance and the voltage amplitude, are admissible accordingly base on EN50160 standard. Furthermore, the harmonics voltages present in this medium are in the accepted range (1.8%) according to IEEE 519 standard. However, the fundamental frequency does not meet the standard, but the difference obtained has no adverse effect.

Like others countries of the world, in Niger also, we are witnessing an increasing use of non-linear electric loads in the domestic, hospital and industrial sectors. However, these loads degrade the shape of the electrical signal and cause disastrous effects to the equipment of the distribution system and the devices which are connected to the network. This article highlights the presence of electric harmonics in the distribution network in Niamey city. In order to do this, measurements were taken at the secondary level of the substations using an energy quality analyze r (FLUKE 1735). By using this measuring instrument, we quantified the voltage and current Total Harmonic Distortion (THD) in the three substations. The results obtained show that, although the statutable rates set by the standards are not exceeded for phase conductors, the neutral contains a very critical percentage of distortion on the residential and hospital substations. Moreover, this assessment made it possible to observe the variation of harmonics in the presence of voltage drops.

The use of solar energy in sunny countries is an efficient way to overcome the energy shortage. The interest of this energy is not only economic but also environmental, as it emits few greenhouse gases. Niger, a vast landlocked country in the Sahel, is characterized by an average sunshine duration of 8.5 hours per day and an estimated average level of sunshine of around 5 to 7 kW/m2 per day. However, the rate of access to electricity in Niger remains very low. To address this problem, a 7MW solar photovoltaic power plant has been built by the State of Niger in the town of Malbaza. It is composed of monocrystalline photovoltaic panels and injects its energy into the national grid.  The objective of this study is to compare the performance ratio determined by measurements with that obtained by simulation under PVsyst in order to evaluate its efficiency. The study is based on annual energy production data, recorded at the site, from 1 January 2021 to 31 December 2021. The annual average values of the global irradiation of the site, the energy produced by the system and the energy injected into the grid are respectively 249.86kWh/m², 1225.25MWh and 972.62MWh; those of the ambient temperature and the performance ratio (PR) are respectively 29.78°C and 0.795. The global losses caused by meteorological phenomena and those linked to the technologies of the various components of the system are evaluated at 20.10%.

Abstract:Since the discovery of electric energy, several improvements have been made by scientists, so that, suppliers can permanently guarantee a quality power to customers. In addition, the introduction of high-tech equipments in all sectors of activity has increased the level of harmonic disturbances in electricity distribution networks. Thus, power systems are subjected to harmonic disturbances injected by these loads and entail effects on the equipments of the distribution network itself and on that of the customers connected there to. In Niger, thereis a constant increase in these types of loads, although there is no complete renewal of energy consuming loads (incandescent bulbs, Cathode Ray Tube (CRT) televisions, fans, etc.). It is necessary to study the behavior of the harmonic rate generated by these loads connected to the distribution network in order to anticipate on the consequences [1]. This article presents a study on the behavior of harmonic distortion rate in current generated by linear, nonlinear and mixed loads in offices at Niamey, Niger. Using an electric analyzer (CA8220), a study on the behavior of harmonic distortion rate in current generated by linear, nonlinear and mixed appliances was conducted. To do this, it studied the variation of the harmonic content by acting on polluting loads (a compressor and an air conditioner), very polluting loads (a computer and an ultrasound machine) and a pure load (a water heater). The results show that a combined and simultaneous use of appliances with nonlinear and linear loads (mixed loads) makes it possible to attenuate the overall harmonic rate, compared to a use of the nonlinear loads alone in the network.

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