-
Developing Gradiometer to Reduce the Low Frequency Noise of Magnetic Sensor with Amorphous Wire
Issue:
Volume 9, Issue 2, April 2021
Pages:
33-40
Received:
29 March 2021
Accepted:
13 April 2021
Published:
23 April 2021
Abstract: Pico-Tesla level high sensitivity magnetic sensor has been developed using FeCoSiB amorphous wire as the core of a coil, but the low frequency noise of the magnetic sensor is somewhat high, and some applications of magnetic sensors, such as magnetic microscope or deep defect detection, require that the sensors have low noise at low frequency. To reduce the noise, it is necessary to know the noise sources of the magnetic sensor. By measuring the noise spectrum of each part of the magnetic sensor with FeCoSiB amorphous wire was measured, it was found that the white noise of the magnetic sensor was mainly determined by the noise of the preamplifier and the low frequency noise was mainly determined by the low frequency noises of the DC bias current and AC bias current of the FeCoSiB magnetic sensor. To reduce the low frequency noise of the magnetic sensor caused by the bias current noise, an electrical gradiometer composed of two magnetic sensors sharing the same DC bias current and AC bias current was developed. The results proved that the gradiometer was not only effective to reduce the low frequency noise caused the bias current, but also effective to reduce the environmental noise caused by the 50 Hz line interference. Using the gradiometer, an eddy current testing (ECT) system were constructed, and the deep defect with the depth of about 8 mm in an aluminum plate was successfully detected by the ECT system.
Abstract: Pico-Tesla level high sensitivity magnetic sensor has been developed using FeCoSiB amorphous wire as the core of a coil, but the low frequency noise of the magnetic sensor is somewhat high, and some applications of magnetic sensors, such as magnetic microscope or deep defect detection, require that the sensors have low noise at low frequency. To re...
Show More
-
Making Energy Savings by the Engagement of Small and Medium-sized Enterprise on Energy Management
Isaac Ayebah Adams,
Samuel Gyamfi,
Christian Kwaku Amuzuvi
Issue:
Volume 9, Issue 2, April 2021
Pages:
41-48
Received:
23 November 2020
Accepted:
16 March 2021
Published:
8 May 2021
Abstract: Small and medium-sized enterprises (SMEs) are crucial in every economy, comprising ninety-nine percent (99%) of enterprises and providing about sixty percent (60%) of employment. They contribute about fifty percent (50%) of global gross value addition and between sixteen percent (16%) to about eighty percent (80%) of gross domestic product (IEA, 2015). Individual SMEs use small amounts of energy, but their collective energy demand is considerable. The International Energy Agency (IEA) estimates SMEs to consume more than thirteen (13%) of total global energy demand i.e. about 74 exajoules (EJ). Effective energy efficiency measures can save as much as 30% of consumption, namely 22 EJ, which is more than the energy used by Japan and Korea per year (IEA, 2015). Therefore, the increase in energy efficiency offers a substantial value for economies, societies and SMEs. This research looks at how SMEs in the Sunyani Municipality take seriously their energy consumption and how energy management can help reduce energy cost through efficiency improvement and increase profitability and growth of their businesses. The study was designed into two forms. Firstly, the energy use practices of the SMEs were investigated. Secondly, the study applied energy auditing method to identify energy reduction strategies that can help reduce the energy consumption of the SMEs. The results reveal that, majority of energy consumers in SMEs do not pay attention to their energy consumption patterns as indicated by 92% of the respondents interviewed. The increase in energy consumption among SMEs could be attributable to the increase in electricity bills. The energy audit identified energy conservation opportunities that can help reduce energy usage in the various SMEs such as switching from CFL and T12 lamps to LED bulbs, replacing old refrigerators, hair driers and industrial irons with more efficient ones, and replacing worn out equipment with high energy efficient ones. The study recommends the use of public education in a paradigm shift from the use of old appliances to new ones in order to save energy and cost.
Abstract: Small and medium-sized enterprises (SMEs) are crucial in every economy, comprising ninety-nine percent (99%) of enterprises and providing about sixty percent (60%) of employment. They contribute about fifty percent (50%) of global gross value addition and between sixteen percent (16%) to about eighty percent (80%) of gross domestic product (IEA, 20...
Show More
-
Performance Evaluation of the Navrongo Solar PV Power Plant in Ghana
Morrison Amenyo Vehe,
Christian Kwaku Amuzuvi
Issue:
Volume 9, Issue 2, April 2021
Pages:
49-59
Received:
25 April 2021
Accepted:
14 May 2021
Published:
20 May 2021
Abstract: The electric power-driven economy of Ghana has necessitated the continual balance of demand with supply by making use of economically feasible sources of energy. In this paper, a 2.5 MW grid connected solar photovoltaic (PV) power plant in Navrongo is evaluated for its performance in 2014. The plant’s output energy, including PV modules, and system efficiencies with other performance indicators were analysed based on IEC 61724 standard. The average ambient and PV module temperature determined was 31°C and 45°C respectively, with 514 W/m2 as the average global radiation. The monthly daily average energy generated was 10.7 MWh with 320.5 MWh and 3845.8 MWh as total monthly average and annual generated energy respectively, during the period. The respective average array, reference, and final yields in hours per day (h/d) were 0.48, 0.51 and 4.13 as well as 18% Capacity Factor, and 81% Performance Ration. A total of 3768.0 MWh was delivered and the PV modules, inverter and system efficiencies were 10.1%, 84%, and 10.3% respectively. In conclusion, it was identified that, dust accumulations on the PV modules surface, significantly reduces the output power due to inefficient use of solar irradiation. Effective and efficient cleaning of the PV modules surface is therefore recommended for improved efficiency of the plant. The aim of this research; therefore; which was to evaluate the performance of the Navrongo solar PV power plant and optimise the energy output efficiently by the use of modelling and simulation has been achieved.
Abstract: The electric power-driven economy of Ghana has necessitated the continual balance of demand with supply by making use of economically feasible sources of energy. In this paper, a 2.5 MW grid connected solar photovoltaic (PV) power plant in Navrongo is evaluated for its performance in 2014. The plant’s output energy, including PV modules, and system...
Show More
