نشریه فناوری های نوین مهندسی برق در سیستم انرژی سبز
سال دوم شماره 2 (پیاپی 6، تابستان 1402)

In solid state lasers, the light pumping of the laser rod is done by a flash lamp. In order to drive the flash lamp, an electrical power supply consisting of four main parts is used, including the capacitor charging power supply, the trigger circuit, the pulse forming network and the simmer circuit. Using the high voltage output of the trigger circuit, the xenon gas inside the flash lamp is ionized. After the trigger action, the main task of the simmer circuit is to generate a low current in order to maintain the ionized state of the flash lamp. Using the simmer mode increases the life of the flash lamp and also significantly reduces electrical and electromagnetic interference. In this article, a new simmer circuit is proposed for driving flash lamp in solid state laser. The presented circuit has been completely designed and then simulated in the PSPICE software environment. After confirming the correctness of its operation, the proposed circuit has been implemented in a laboratory. Circuit simulation results and laboratory results are presented and reported in this article.

This paper proposes a new ultra-compact strip metal-insulator-metal (MIM) plasmonic waveguide on a silicon-on-insulator (SOI) platform. The waveguide structure can efficiently propagate surface plasmon polaritons (SPPs) within a thin low-index SiO2 layer at an optical wavelength window of 1550 nm. The main parameters of effective refractive index, propagation length, confinement factor, and effective mode area were determined for the proposed waveguide with different waveguide widths. The simulation results were comparable with the in-plane MIM plasmonic waveguide. The proposed layer stack could be monolithically integrated with conventional and hybrid plasmonic SOI-based devices and has the potential of focusing light to nanoscale dimensions.

In this article, a multi-input non-isolated converter topology with high gain is proposed for clean energy applications that require an energy storage system. The techniques of voltage multiplier cell and coupling inductor have been used to design the circuit, and by combining them, it is possible to use switches with low voltage stress and as a result, low conductivity. The charging performance of the energy storage system is explained and the structure and performance of the proposed converter are investigated for the design of a non-isolated multi-input converter with high voltage gain. The precise design method for the correct operation of the converter is presented and the simulation results of the converter performance are shown. Finally, in order to verify the accuracy of the results obtained from the simulation of the proposed converter, a laboratory sample has been made and a comparison has been made between the results.

In power smart grids, equipment and electrical infrastructure and information smart grids in order to increase efficiency, improved reliability and reducing environmental pollution merged together. One of the basic challenges in such grids, increase uncertainty due to the use of distribution generation sources contain are renewable resources. In recent years has proposed the concept of the micro grid, it means a medium voltage distribution grid or low voltage grid includes distribution generation units, storage devices and different controlling loads with operational capability in both cases grid-connected and islanded. Because micro grid in the islanded, grid is with small power generation units, the smallest error it may be cause instability. It is therefore necessary so when passing through grid-connected to island make sure of sufficient storage in distribution generation generator according to their production capability curve in order to satisfy loads reactive and active power. The main focus of this research is on distribution generation unit’s reactive and active power scheduling for sustainable and economic operation from a micro grid. The need for a sustainable transition from grid-connected to island in case of an error in grid is one of the most important constraints in the micro grids. Therefore, must to be investigated economic scheduling of distribution generation units a micro grid considering these constraints. It should be noted that consideration these constraints in reactive and active power scheduling of distribution generation units can bring on more economic benefits in the steady pass from grid-connected to island. So, in this research will be presented formulation related to planning reactive and active power of distribution generation units by maintaining the constraints that its objective function will be to minimize the cost of power generation.

In this paper, a new soft switching boost converter is presented. A lossless active snubber circuit including an auxiliary switch, three diodes, a capacitor and a coupled-inductor provides soft switching conditions for the main switch and the output diode, so that the main switch and the output diode operate under ZCS and ZVS conditions, respectively. They turn on and off under the ZCS condition. The operation of the snubber circuit is associated with low current stress on the main switch and low current and voltage stress on the output diode. The proposed converter is able to maintain the smooth switching condition in a wide range of output load and input voltage variations. Working principles, steady state analysis and design procedure of this converter are discussed in detail. Also, to confirm the theoretical results, a laboratory sample is made and tested. It should be noted that, The laboratory results confirm the theoretical results comprehensively.

The need for high reliability of modern ships has led to the development of a zonal structure for their electrical distribution systems. One of the most important challenges of the electric distribution systems of modern ships with a zonal structure is their protection in the event of a fault to maintain stability and reliability at an acceptable level. Failure to detect the fault and to isolate the faulty section at the proper time has disastrous consequences for the shipboard electrical system. This paper aims to present an effective protection scheme for all equipment of the hybrid AC/DC distribution system of ships with a zonal structure. In the proposed scheme, protection against single-phase to ground faults is performed using a high-resistance grounding system and timer, while the current of two-phase and three-phase faults is cleared using the fuse-isolator-switches. The use of a high-resistance grounding system allows uninterrupted operation of the ship's electrical system when single-phase to ground faults occur. Due to not using protective relays, the cost of the proposed scheme implementation is low. The proposed protection scheme includes primary and backup protections and does not require communication infrastructure. Also, all equipment of the ship's electrical system including generator, propulsion motor, busbar, feeder, line, load, and direct current system are considered in the proposed scheme. The coordinate operation of the developed protection scheme is assessed on the ETAP simulation model of a test zonal electrical system of the ship.