This paper presents a dynamic UNINTERRUPTIBLE POWER supply (DUPS) consisting of both battery and flywheel energy storage systems with the aim of overcoming POWER quality problems such as temporary voltage drop and POWER outages. To supply a critical load at the moment of fault occurrence and a few seconds later, the flywheel energy storage system(FESS) and for a few minutes after that or in the case of POWER outage, the battery storage system and after that, a diesel generator are used respectively. The FESS system consists of a bidirectional inverter, a flywheel and an interior permanent magnet synchronous motor (IPMSM). In the IPMSM control scheme, vector control, torque maximization per ampere(MTPA) and field weakening technics are used. The battery energy storage system consists of a bidirectional DC / DC buck-boost converter and a charge-discharge control. The simulation results show that the FESS changes from standstill to charged and standby condition in less than10  seconds and is ready to supply critical load for short-term phenomena. In UPS mode, it also maintains the critical load voltage at the nominal value in less than one cycle. In the event of a long-term POWER outage, after discharging the flywheel energy for about 2 seconds, the battery energy storage system maintains the DC link voltage at its reference value and provides the necessary time to start the diesel generator.

POWER SUPPLIES which are commonly used in pulsed lasers with the mechanism of electrical pumping are in fact a kind of pulse generator. These systems are of particular importance due to their wide variety of applications, and their use in pulsed lasers are the most important subject of interest. In this article specifications of a pulsed generator which is designed for metal vapor lasers such as CVL lasers will be introduced. Details of the designed circuit, construction, and measurements of the working parameters will be also presented. The maximum output voltage is 10 kV with the pulse width of ~1µsec. The average current is 340 mA and the pulse repetition rate is 29 kHz.

In this study, the design and operational performances of a double thyratron, model TGI1 1000/25, connected in parallel to be applied in metal vapor lasers (MVLs) and their effects on heat dissipation and other limiting factors such as average current ; plate breakdown and anode heating factors; are presented. The sharing frequency between the used thyratrons is the main factor which is used in the applied design. Our measurements for the ohmic and capacitive loads, and also the laser tube with the use of anode tank water temperature measurements to obtain the heat dissipation in two different designs consist of single and double thyratrons configurations show that in the latter design, the average current and the heat dissipation are reduced to their half values compared to those of the former design. With the obtained experimental results, it is possible to apply a number of low POWER thyratrons in high POWER MVL lasers, where their input electric POWERs are higher than 2.5kW.

High POWER pulses with low widths have many applications in radiation generator devices as flash radiography and high POWER microwave generators. One of the compression methods of high POWER pulses is magnetic pulse compression. In this paper a Tesla generator with saturated core which produces a 200k V voltage pulse has been designed and then the effect of saturation of the core in the compression of the output pulse using Proteus and CST EM Studio codes was studied. Our studies showed that with saturation of the transformer’s core, the magnetic permeability and hence the inductance of the transformer’s coils will decrease and consequently the frequency of current oscillations in the transformer will momentarily increase where it will result in the decrease of the output pulse width.

This paper presents a detailed circuit analysis and PWM implementation of a fuel cell based Z-source converter using L and C components. The Z-source converter uses the shoot-through that simultaneously turns on both POWER switches in a leg in order to boost a DC-link voltage. A discrete time state space model of the Z-source converter is given for DSP implementation. Also, a modified space vector pulse width modulation is described in detail for stepping up the DC-link voltage and generating a sinusoidal AC output voltage. To verify the effectiveness of the analyzed circuit model and modified space vector PWM technique, simulation results using Matlab/Simulink will be presented under an open-loop control and a closed loop control.

In this paper, a novel risk-based, two-objective (technical and economical) optimal reactive POWER dispatch method in a wind-integrated POWER system is proposed which is more consistent with operational criteria.  The technical objective includes the minimization of the new voltage instability risk index. The economical objective includes cost minimization of reactive POWER generation and active POWER loss. The proposed voltage instability risk employs a hybrid possibilistic (Delphi-Fuzzy)-probabilistic approach that takes into consideration the operator’s experience, the wind speed and demand forecast uncertainties when quantifying the risk index. The decision variables are the reactive POWER resources of the system. To solve the problem, the modified multi-objective particle swarm optimization algorithm with sine and cosine acceleration coefficients is utilized. The method is implemented on the modified IEEE 30-bus system. The proposed method is compared with those in the previously published literature, and the results confirm that the proposed risk index is better at estimating the voltage instability risk of the system, especially in cases with severe impact and low probability. In addition, according to the simulation results compared to typical security-based planning, the proposed risk-based planning may increase the security and economy of the system due to better utilization of system resources.

Considering simplicity of the practical implementation, application of the sliding mode control in POWER electronics converters has increased in recent years. Equivalent control approach can be used to stabilize the converter switching frequency in sliding mode control of the converters. In this approach, controller gains are tuned by trial and error and hence, stability of the controller cannot be guaranteed in a wide range of operation. To cope with this problem, a novel approach for sliding mode controller design as well as gains selection in flyback switch mode POWER SUPPLIES is developed in this paper. Also, adaptive backstepping and sliding mode nonlinear controllers are compared considering different criteria according to experimental tests in a wide operating range. Evaluation criteria are steady-state error, converter dynamic response during start-up, robustness of the controller against load and line changes and finally, ease of practical implementation. Using Texas instruments digital signal processor (DSP-TMS320F2810), practical responses of the developed controllers are presented. Also, simulations are accomplished using MATLAB/Simulink software.