Simplified cascade multiphase DC-DC boost power converters for high voltage-gain and low-ripple applications

This paper proposes two new simplified cascade multiphase DC-DC boost power converters with high voltage-gain and low ripple. All simplifications reduce the number of active switching devices from <em>2N</em> into <em>N</em>, where <em>N</em> is the phase number. The first simplification reduces the number of inductors from <em>2N</em> into <em>N+1</em> and increases the number of diodes from <em>2N</em> into (<em>2N+1</em>). The second simplification reduces the number of inductors from <em>2N</em> into <em>N+1</em> and increases the number of diodes from <em>2N</em> into (<em>3N+1</em>). The second simplification needs inductors with smaller current rating than the first simplification. The expressions of output voltage as a function of load current are derived by taking into account the voltage drops across the inductors and switching power devices. Simulated and experimental results are included to show the basic performance of the proposed cascade multiphase DC-DC boost power converters.

Integrated use of Smart Grid technologies in railway traction networks

The purpose of the paper is to develop a methodology for modeling railway power supply systems equipped with a set of devices implemented on the base of smart grid technologies. The research is carried out using the Fazonord software package designed for modeling the modes of railway power supply systems in phase coordinates. The calculation model is implemented for the power supply system of a two-track section with five traction substations. The results obtained show that reliable and high-quality power supply of train traction and non-traction consumers can be ensured on the basis of the integrated use of active Smart Grid elements, such as a phase number converter, active harmonic conditioner, controlled reactive power source, and a distributed generation unit. Computer simulation allows to establish that in the absence of reactive power sources there are noticeable voltage fluctuations on 10 kV buses of non-traction consumers; the asymmetry is approaching the limit of normally acceptable values; disabling of the active filter results in the increase of the total harmonic coefficient of voltages up to 16%; if the entire complex of active devices is available, the high quality of electrical energy is achieved; the phase number converter is robust and features low sensitivity to the errors in parameter setting; voltage deviations caused by the limited variation range of reactive power in the reactive power source are short-term and do not exceed the values acceptable in practice. Thus, on the basis of Smart Grid technologies, distributed generation units can be connected directly to the traction network using a phase number conversion device formed according to the reciprocal Steinmetz circuit. Elimination of harmonic distortions created by rectifier electric locomotives is carried out by means of an active conditioner of higher harmonics. A controlled reactive power source can be used to maintain voltage levels.

Automatic Working Phase Picker for Domestic load from Three phase supply

Absence of phase is a very common and serious problem in every sector, at home or workplace. Many times, one or two phases in three phase supply cannot be live. Regardless of this, certain electrical equipment in one room and OFF in another room would be on, several times. This causes considerable disturbance to our routine work. This paper is intended to test the availability of any live phase, and will only link the load to the specific live phase. There is only one phase available, and then the load will still be ON. The idea is conceived with ARDUINO. This controller continually checks the live state of all connected phases, using a Relay the load is connected to active phase by controller. Transistor is operated the relay.When two or more phases are active but load is only connected to phase 1,that active phase number is display in LCD for observation.

Evaluation of the stability of the parametric phase number converter

In the article related issues to the stability assessment of a parametric converter of the number of phases of a ferroresonance nature are analyzed. The areas of change in the characteristic parameters of the converter that guarantee its stable operation are considered.