Majlesi Journal of Energy Management
Volume:2 Issue: 3, Sep 2013

An improved charge pump circuit for high-voltage applications is presented. The advantage of this circuit is that its topology is simple, and it can produce a higher DC voltage and potential energy compared to conventional methods. The output is a quadratic polynomial function of the cascade stage number, times the amplitude of the first stage''s input voltage and it reduces the required dielectric breakdown voltage in lower stages compared with conventional circuits, for the same output value.

40% of total world electricity consumption is approximately consumed by electric motors. Researches show that, hospitals represent approximately 6% of total energy consumption in the utility buildings sector. Electric motors in a hospital represent approximately 19% of the total energy consumption. In this paper, the research papers and practical studies on energy efficiency and energy saving potentials on electric motors at the hospitals are presented. Under the following sections, the latest literatures including research articles, conferences, e-books, handbooks, reports, web pages, MSc and PhD theses interested in energy efficiency, energy saving and energy management on electric motors are summarized. Payback period calculations of some projects on electric motors are also presented.

In this paper deals with the modeling and simulation of IEEE 14-bus system using interphase controller. The simulations results are obtained by using MATLAB-simulink. Simulations results are obtained for the dynamic case studies. This paper mainly proposes a modified IEEE-14 bus system with an enhanced power quality. Simulations results are compared with conventional IEEE-14 bus with proposed system by using interphase controllers.

So far a variety of methods were applied to optimized placement of distributed generation which we can refer to casual-based algorithms such as PSO, analytical method and load flow method. In this paper, we have used an analytical method based on minimizing loss and generalized it for simultaneous placement of two DGs in two sample networks and we have found the best places and capacities for installation of DGs. And, for investigating the value of the results, the investigation method for all modes is applied in this network. Moreover, the results were compared with the results obtained by PSO method. 33 and 69 buses systems were studied too. The findings show that the proposed method is more accurate than PSO method, and its convergence speed is better than that of the investigation method for all possible modes.

A new ZVZCS bidirectional DC-DC converter for DC Uninterruptable Power supplies is presented in this paper. The usual way to avoid a computer shutdown during a mains failure is to connect an ac uninterruptible power supply (UPS). Alternatively, in this paper, a simple and high efficiency dc UPS is presented by an isolated bidirectional soft-switching dc-dc converter. The bidirectional dc-dc converter operates under zero voltage and zero-current switching (ZCS) conditions by adopting auxiliary resonant circuit to the main switches. ZVZCS operation is achieved only in battery-backup and ZCS condition in charging mode, which significantly reduces the power losses in the bidirectional converter. The principle of operation is analyzed and simulated by using MATLAB simulink.

In order to make effective usage of electrical power in drilling rigs power system need to solve the problem of reactive power compensation on that system. Therefore, in this thesis is considered the optimal model for the loads of drilling rigs and sets the bit driving force. There are nonlinear and time-varying loads in Drilling rigs power system. Achieve an optimal model for the driving force of the drilling bit and the loads of drilling rigs is required. Until with it help can design optimize compensation for this industry. Generally can be said the compensators of reactive power divided into two groups, one reactive load compensation and other compensation terminal voltage to keep a constant terminal voltage. In order to effectively compensate for dynamic changes in system is necessary compensation, Firstly have a fast and accurate control susceptance, Secondly could measured load quantities, Thirdly is performed high-speed signal processing. As for the importance of reactive power compensation in the drilling rigs power systems, Be done modeling of an optimization model and then design and simulate an optimal compensation the thyristor controlled reactor (TCR) will be discussed and Harmonic filters are necessary to give with this compensator. Finally, The advantages and disadvantages of this compensation to the other compensators will be reviewed and analyzed.

Day-ahead market is one of the methods that Generation companies (GENCOS) use it for planning electricity market bidding strategies for days ahead. In this paper calculations of costs and profits are dynamically and separately in different periods called segments. Some of features of this paper are: uncertainty of GENCO’s offering price for selling power of all GENCOS and fuel’s price, maximum profitability of suggesting amount of energy for selling by GENCOS in the critical situation of competitive electricity market, including emission penalty and it’s influence on the costs and using exact relation between output power and fuel price. Genetic algorithm is used in this paper for suggesting the best amount of power for selling in each segment in order to gain the maximum available profit. Normal distribution is used for modeling the uncertainty of offering power of other GENCOS and fuel cost. Objective of the critical situation of market is when the all other rival GENCOS are at their most profitability.