Use of magnetic field calculation tools to design MV/LV substations

Medium Voltage (MV) to Low Voltage (LV) Substations are one of the last links in the distribution process of Electric Power. Associated with these is the generation of magnetic field. These have generated great concern in the population due to its possible link to health effects in humans, so it is necessary to know what are the levels generated by existing and new facilities, considering different constructive topologies. To achieve the objective, magnetic field calculations are performed using 3D simulation tools, allowing to reproduce the layout of ground level substations, knowing the magnetic field values for different loading conditions and considering balanced and unbalanced load conditions, with current in neutral conductors. In 2013 measurement campaigns of Magnetic Field on substations were performed, also loads were surveyed. The results of the calculation of magnetic field generated by ground level substations, considering different topologies used in Argentina are presented in this paper. In order to validate the results, comparisons between measured and calculated values are performed. Generated levels are studied for different cases. Obtained magnetic fields values are compared with limits of Argentinean regulation and recommended references values by international organizations such as ICNIRP (International Commission on Non-Ionizing Radiation Protection) and IEEE (Institute of Electrical and Electronics Engineers).Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

HV Underground Cables Magnetic Field Mitigation Measures

The non stopping growth of urban centers and increasing demand for electrical energy causes more high voltage lines and underground cables installed in cities. As a direct consequence, the generation of Magnetic Fields (MF) is increased due to the new power lines and cables. Magnetic Fields have raised concerns in the population for years by its association with possible health effects. Before building new facilities it is necessary to assess whether these would meet the requirements of the regulations. Thus it is necessary to have tools that quantify the MF values emitted by the planned facilities. In the laying of cables, two zones are identified. The first one is where the phases are regularly laid close to each other. The other area is where the joints are made. In this area is where the distances between phases are higher. In the latter, the magnetic field values are higher due to the increase of the separation.Trabajo C3-203. 46ª CIGRÉ SESSION (International Council on Large Electric Systems).Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctrico

Influence of the representation of the distribution transformer core configuration on voltages developed during unbalanced operations

The object of this paper is to emphasize the importance of the representation of the core configuration when seeking transients developed in a distribution transformer under an unbalanced situation. Digital time-domain simulations are performed with the Alternative Transients Program (ATP) for the case of a distribution three-phase transformer using the following two core configuration representations available in the ATP: three-legged core form and fivelegged core. Severe overvoltages and high saturated currents would not be evidenced if the wrong core configuration representation was used during simulations.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Experience in the design of external protection systems against lightning

This paper describes the experience acquired during the revision and determination of external lightning protection systems in some refinery plants, in Argentina. With this purpose a program, developed by IITREE, based on the Monte Carlo statistical technique, was used, among other things, to determine in a period of time the frequency of lightning flashes to structures. International and American standards were used as reference.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Experience in the design of external protection systems against lightning

This paper describes the experience acquired during the revision and determination of external lightning protection systems in some refinery plants, in Argentina. With this purpose a program, developed by IITREE, based on the Monte Carlo statistical technique, was used, among other things, to determine in a period of time the frequency of lightning flashes to structures. International and American standards were used as reference.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Reactive an harmonics compensation in a medium voltage distribution nertwork with active filters

This paper presents the design of a shunt active filter to compensate reactive power and harmonics in the medium voltage level of a power distribution system. Reconfiguration of the power delivery network imposes new constraints in a distribution substation so that the reactive compensation should be increased. The alternative of shunt active filter compensation connected to the 13.8 kV level is analyzed. Two alternatives are proposed, the first one considers full compensation with the active filter while the second one uses the existing capacitor bank and builds the complementary compensation with the active filter. In the last case, the capacitor bank is modified to make a 5th harmonic filter to avoid system resonances. Both proposals show very good performance.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

HV Underground Cables Magnetic Field Mitigation Measures

The non stopping growth of urban centers and increasing demand for electrical energy causes more high voltage lines and underground cables installed in cities. As a direct consequence, the generation of Magnetic Fields (MF) is increased due to the new power lines and cables. Magnetic Fields have raised concerns in the population for years by its association with possible health effects. Before building new facilities it is necessary to assess whether these would meet the requirements of the regulations. Thus it is necessary to have tools that quantify the MF values emitted by the planned facilities. In the laying of cables, two zones are identified. The first one is where the phases are regularly laid close to each other. The other area is where the joints are made. In this area is where the distances between phases are higher. In the latter, the magnetic field values are higher due to the increase of the separation.Trabajo C3-203. 46ª CIGRÉ SESSION (International Council on Large Electric Systems).Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctrico

Wind Power Integration on Interconnected or Isolated Upstream Facilities

In this paper electric studies considering an oil upstream facility with wind power and conventional generators are presented. Static power flows are performed. The voltage variations and reactive power requirements are analyzed. Also dynamic fault simulations, with and without the island formation are performed. The objective is to assess the impact of wind power generation to be included in a typical facility, in order to achieve a satisfactory performance. This work simulates a typical upstream facility, conformed by a 10.1 kV oil network a conventional motogenerator and different types of wind power plants. Wind turbine models and controls for electromechanical transients are used.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE

Design of mechatronic systems through aspect and object-oriented modeling

Design of mechatronic systems involves the use of multiple disciplines, from mechanics to electronics and computer science. Different granularities of hybrid co-simulations with increasing details can be used during the design process. However, there is the need of modeling tools for effectively managing the necessary abstraction layers. This work proposes a combination of Aspect-Oriented and Object-Oriented modeling for reaching the goal. Moreover, it shows how the utilization of these tools can facilitate design-space exploration, segregation of domains of expertise and enhances co-design

Active and hybrid filters in medium voltage distribution power systems

This paper presents the design of different topologies of active power filters to compensate reactive power and harmonics in the medium voltage level of a distribution power system. One pure active filter and two hybrid topologies, are implemented. A pure active compensation is obtained with a Shunt Active Power Filter (SAPF). The shunt combination of SAPF and passive filter, form one of the hybrid topologies implemented, named Shunt Hybrid Active Power Filter (SHAPF). The other hybrid topology, called Hybrid Shunt Active Power Filter (HSAPF), connects the active filter in series with two shunt passive filters. The control algorithm are implemented with the d-q theory measuring the system current to compensate the load, setting a feedback control loop, rather than a simple feedforward compensation. Simulation for different load demands and distortions are performed. Finally a comparative evaluation of the different filters is carried out.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctricos (IITREE