Journal Volume 15 Issue 2

Study of Single Sensor Based Maximum Power Point Tracking Techniques for Solar Water Pumping System

E-mail Print PDF

Amine Daoud, Abdelhamid Midoun

This paper describes new techniques of maximum power point (MPP) tracking for solar water pumping system. The latter system consists of a PV array, a DC/DC buck converter and a universal motor coupled to a centrifugal pump. A conventional hill climbing method is employed to seek the MPP using the motor-pump rotation speed or the pump outlet pressure information. Experimental results are presented and a comparison with conventional algorithm which requires both voltage and current sensors is provided.

altDownload full text

Estimation of Optimum Value of Y-Capacitor for Reducing Emi in Switch Mode Power Supplies

E-mail Print PDF

Milind M. Jha, Kunj Behari Naik, Shyama P. Das

Putting a Y-capacitor between the primary ground and secondary ground is a common practice in industry to reduce EMI; but, this capacitor increases touch current. A method is discussed to measure the touch current at circuit design level. An optimum value of Y-capacitor is predicted without exceeding touch current limit. Experimental results of touch current measurements and EMI measurements are analyzed.

altDownload full text

Power Quality and EMC in Smart Grid

E-mail Print PDF

Magnus Olofsson

Smart Grid is increasingly seen as a means to facilitate climate friendly renewable energy sources (renewables) and to enable efficient use of electricity. For example, modern electrical networks can link wind- and solar power with electric cars. A consequence of Smart Grid is a drastic increase in use of electronics in the power system. This makes the satisfactory function of electrical and electronic equipment vital for realization of a robust Smart Grid. This paper focuses on the satisfactory function of equipment for Smart Grid with respect to electromagnetic disturbances, i.e. EMC – Electromagnetic Compatibility including Power Quality. Finally, a framework for the apportioning of responsibilities between network operators and the parties being responsible for the connection of equipment is proposed.

altDownload full text

Czech position to the new version of EN50160 standard

E-mail Print PDF

Karel Prochazka, David Mezera, Petr Bilik

The paper presents general results of a three-year measurement of voltage quality (VQ) carried out at a selected sample of 80 LV distribution networks in all regions of the Czech Republic, both from the point of view of the standard EN 50160:2007 [1] and with regard to its proposed changes [2] elaborated based on the requirements of ER GEG [3]. The paper also deals with possible consequences for DNOs relating to compensations to customers for VQ acc. to ERO Decree [4] an, with the costs for reconstruction of all LV networks, in which some parts do not fulfil the valid EN 50160 and its proposed changes.

altDownload full text

Development of Techno-Economical Objective Function for Supercapacitors Energy Storage System Implemented in Distribution System

E-mail Print PDF

Kuldeep Sahay, Bharti Dwivedi

The development and advancement in storage technologies and custom power devices technologies are making the application of supercapacitors energy storage system a potentially viable solution for modern power distribution system application, permitting the system to be operated in more flexible and controllable manner. The supercapacitors energy storage system considered is supposed primarily for limiting the monthly subscribed demand levels, energy cost saving, for supply of energy in case of instantaneous need and long duration back up purpose. This paper presents the development of techno-economical multi-objective function for SCESS implemented in distribution system considering the constraints and their impact on optimization of net present value.

altDownload full text

Resistance Approximation In High Harmonic Frequencies

E-mail Print PDF

Yuri L. Sayenko, Walid R. Kukhun

The problem of consideration of the resistance in calculation of non-sinusoidal regimes in electrical networks is considered in article. It is shown the necessity of taking in account the skin effect in harmonic frequencies. Using general electromagnetic field theory in condition medium and Bessel’s function allow to obtain expressions of resistance approximations in high harmonics frequencies for conductors of round cross-sectional areas.

altDownload full text

MEA’s Network Connection Regulation

E-mail Print PDF

Tosak Thasananutariya

Metropolitan Electricity Authority (MEA) is a state enterprise power utility in Thailand responsible for supplying electricity to Bangkok Metropolis and two neighboring provinces, namely Nonthaburi and Samutprakran covers a service area of 3,192 km2. In 2008, MEA supplied electric power to 2.92 million customers with the maximum power demand of 7,644 MW or 34% of the whole country...

altDownload full text

Methods for Canceling the Power Frequency Magnetic and Electric Fields at Pre-Specified Points on the Lines' Corridors

E-mail Print PDF

Mohamed M. Saied

Methods are presented for the cancellation of the power line’s magnetic and electric fields at pre-specified points close to the line corridor. For canceling the magnetic field, three auxiliary conductors constituting two mitigating loops are used. Their configuration should be geometrically similar to the arrangement of the 3-phase power line’s conductors, with respect to the point at which a zero magnetic field is required. A procedure is suggested for the optimal selection of the scaling factor relating the power conductors’ and the mitigating conductors’ geometrical dimensions. In a case study, the magnetic field reduction varies between 100% near the zero-field point to 35% to the right of that point, with an optimal scaling factor of 0.15. Similar procedure can be used for canceling the electric field at a pre-specified point...

altDownload full text