Due to the high efficiency and low switching losses of resonant power convertors in comparison with switching convertors, nowadays there is a growing trend towards these convertors. However, because of the high frequency of switching in such convertors, it is quite difficult to present an efficient control method. In this paper, based on the state feedback method and using pole placement technique a control strategy is developed which controlling delay time in the converter’s switching to minimize losses in the induction and hardening furnaces. In the propose method, the input voltage is isolated from output load. Moreover, fewer number of elements are employed in the control circuit which will be caused lower costs and small dimensions for control system. As a result, the proposed controller is more economical in comparison with the conventional ones. To show the effectiveness of propose controller, simulation circuits using PSIM software and an experimental setup are provided and the results are reported

Data centers are the places where servers and IT equipment are installed. In the network and IT, it is hardware that stores the hardware modules such as servers, switches, switches and communication equipment, and UPS and other network equipment. Due to the usual heat release of the orcs, the management of air distribution systems and cooling systems in the data centers are of particular importance to prevent the destruction from excessive heat. the purpose of management of air distribution systems is to solve problems in cooling of data centers, including the minimization of hot air, due to cold weather and removing hot spots, and can also reduce the high cost of cooling systems by removing air circulation problems. in this study, after simulation and analysis of different modes of cooling system design of cooling system, cooling and cooling corridors can be increased from the allowed range and better energy loss and better efficiency and then the return and partitioning of false floors were introduced as supplementary methods. in total, the comparisons were calculated according to an increase of 20 % of the heat from the orcs in the simulated model of

For multi-objective optimal reactive power dispatch (MORPD), a new approach is proposed where simultaneous minimization of the active power transmission loss, the bus voltage deviation and the voltage stability index of a power system are achieved. Optimal settings of continuous and discrete control variables (e.g. generator voltages, tap positions of tap changing transformers and the number of shunt reactive compensation devices to be switched)are determined. MORPD is solved using particle swarm optimization (PSO). Also, Pareto Optimality PSO (POPSO) is proposed to improve the performance of the multi-objective optimization task defined with competing and non-commensurable objectives. The decision maker requires managing a representative Pareto-optimal set which is being provided by imposition of a hierarchical clustering algorithm. The proposed approach was tested using IEEE 30-bus and IEEE 118-bus test systems. When simulation results are compared with several commonly used algorithms, they indicate better performance and good potential for their efficient applications in solving MORPD problems.

Presence of triplen voltage harmonics and circuiting current in a delta-connected cascaded H-Bridge multi-level inverter causes extra power losses. In this paper, a low frequency optimization method is proposed to reduce triplen voltage harmonics in delta-connected cascade H-Bridge multilevel inverters. Using this method, in addition to reducing these harmonics, the total harmonic distortion (THD) is also maintained at optimum level and the requirements of standards such as EN50160, WG36-05 and IEC61000-3-6 are also satisfied.  In this method, using optimal minimization of total harmonic distortion (OMTHD), the optimal values of the switching angles and DC sources are obtained using the Particle Swarm Optimization (PSO) algorithm. The simulation and experimental results show the effectiveness of the proposed method in reducing triplen voltage harmonics and circuiting currents while keeping the THD at optimal levels.

In this paper, slewing maneuver of a flexible spacecraft with large angle of rotation is considered and assuming structural frequency uncertainties a robust minimum-time optimal control law is developed. Considering typical bang-bang control commands with multiple symmetrical switches, a parameter optimization procedure is introduced to find the control forces/torques. The constrained minimization problem is augmented with the robustness constraints, which in turn increases the number of switches in the bang-bang control input to match the total number of the constraint equations. The steps of the solution algorithm to obtain the time optimal control input are discussed next. The developed control law is applied on a given satellite during a slewing maneuver, and the simulation results show that the robust control input with just few switching times can significantly lessen the vibrating motion of the flexible appendage in the presence of structural frequency uncertainties, which reveals the merits of the developed control law.

A reward and penalty scheme (RPS) is used for setting up the service quality which exposes the distribution companies to financial benefits caused by demand for the reliability of customers. In this paper, an algorithm for the optimal switch number and placement in distribution networks in the presence of RPS is presented. The primary objective is reliability improvement and minimization of the cost of sectionalizing switches (SS) and tie switches (TS) for a given regulatory period considering acceptable financial risk. In this algorithm, the uncertainty in the reliability is appeared as financial risk. A genetic algorithm is adopted to solve the optimization problem. The number and location of SS and TS is found while financial incentives of RPS, capital investment and annual operation and maintenance costs are considered. The performance of the proposed approach is assessed and illustrated on a real distribution network. The results show the efficiency of the proposed algorithm.

In this paper, a nonlinear loss minimization control strategy for an interior permanent magnet synchronous motor (IPMSM) based on a newly developed sliding mode approach is presented. This control method sets force the speed control of the IPMSM drives and simultaneously ensures the minimization of the losses besides the uncertainties exist in the system such as parameter variations which have undesirable effects on the controller performance except at near nominal conditions. Simulation results are presented to show the effectiveness of the proposed controller.

A multi-processor architecture was proposed to address power consumption limitations in chips in order to increase performance and lower power consumption. In this architecture, the highest power consumption comes from the chip connections. Optical connections can reduce power consumption and increase performance via a new architecture called photonic network-on-chips, which are capable of utilizing the benefits of optical signals and elements for data transfer. This paper proposes a 4×4, non-blocking photonic switch to improve physical layer parameters by increasing photonic network performance. The insertion loss and energy dissipation of the proposed switch were compared to three switches: Original, StraightPath, and Symmetric switches. The results indicated that, in a mesh topology, the proposed switch reduced loss for the GTC, Cactus, Tornado, and MADbench by 28.22, 24.46, 28.72, and 29.20%, respectively, when compared to the Original switch. According to PhoenixSim simulation results, the proposed switch reduced insertion loss and energy dissipation in photonic network-on-chips when compared to the three comparison switches.

In this paper، design، analysis and fabrication of a low loss capacitive RF MEMS shunt switch، which made on the coplanar waveguide transmission line and alumina substrate in the frequency band of 40-60 GHz، is presented. The CPW is designed to have 50Ω impedance matching on the alumina substrate. Then the desired switch is designed with appropriate dimensions. Afterward the important parameters are obtained by finite element and full-wave electromagnetic simulations by CoventorWare and HFSS. It is shown that for the designed switch، pull-in voltage is 19. 25v، insertion-loss is 0. 8dB، return-loss is more than 9. 8dB and the isolation is 50dB. At the end، the laboratory sample of designed switch is fabricated on alumina substrate and tested، and the possible parameters are obtained. We concluded that the designed switch has appropriate insertion and return loss and good isolation، and fabricated switch has acceptable properties.

To convert the DC voltage and current levels of DC-DC power converters is used. This is not ideal because pieces of power converters are the disadvantages that this may result in loss of productivity in them. Among the weaknesses that are discussed in this converters dissipate them. The toll that this type of converters and other power converters switching losses suffered soft switching techniques have been proposed to solve it. In fact, these methods overlap when switching voltage and current at high levels prevents the key. Moreover, the use of three-level structure causing it to drop to about half the input voltage is voltage power switches. This is also a great impact in reducing switching losses and extend the life of power converters. In this article the basic definitions and concepts of power converters, two major types of soft switching techniques are examined and compared in terms of productivity. Also went on a three-level DC-DC converters are the best examples of a MATLAB simulation software and the results of its soft switching is provided at the end.