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PWM controlled rectifiers can efficiently and economically be employed in low and medium power applications of dc drives and in front-end converters of rectifier–inverter systems while maintaining the advantages of design simplicity and operation reliability of naturally commutated schemes. Due to the high dc voltage that is produced which is great...
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... steady state analysis procedure is aimed at modeling the converter in order to obtain an approximate equivalent circuit for ac–dc buck-boost converter. Fig. 4 shows the steady state inductor current and voltage waveforms during one complete switching cycle for a continuous and discontinuous inductor current. Due to the use of high switching frequency, the input voltage can be assumed constant during the switching period. The inductor voltage v L is the input voltage v during the charging mode and is the output voltage v o during the discharging mode. For constant switching frequency and quasi steady state analysis of the switching converter, the average inductor voltage during each switching cycle can be given as a function of the chopper duty cycle d ...
Context 2
... steady state analysis procedure is aimed at modeling the converter in order to obtain an approximate equivalent circuit for ac-dc buck-boost converter. Fig. 4 shows the steady state inductor current and voltage waveforms during one complete switching cycle for a continuous and discontinuous inductor current. Due to the use of high switching frequency, the input voltage can be assumed constant during the switching ...
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Citations
... As far as the HPQ rectifiers are concerned, several buck, boost, and buck-boost converters derived solutions have been published in [16][17][18]. However, buck and boost derived HPQ rectifiers exhibit limited applicability in single stage E2Ws/E3Ws charging systems compared to their buck-boost counterpart [18]. ...
... Notably, this state occurs due to the DCM operation of the circuit. Further, the key expressions corresponding to this state, are provided as follows, From Eqs. (14) and (15), M, and V C1 , are derived and given as, Similarly, from Eqs. (16) and (17), the average inductor currents I Li and I Ls , are evaluated and given as, From Eq. (18), it is clear, that the presented switched inductor modified Zeta rectifier ensures more steeper VTR than conventional Zeta HPQ rectifier, both in CCM and DCM conditions. ...
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... The current research deals with one of the most important electronic transformers, the alternating current transformer [61][62][63]. Where its importance is through what it performs as it works to give a variable output from a source The transformer is an electronic switch that conducts the electronic switching of the switches and we get a change in the opening and closing state with a certain frequency. ...
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power devices that work as transformers and are named
according to the function. A model of a single-phase
transformer AC-AC type with half-wave and full-wave quality
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and current, which is considered an input to the load. The
fixed input transformer has a variable output according to the
required power, voltage and current. Inverters of this type
have so many uses that they are used in many different
applications, including industrial, induction motor speed
control, military, medical and household, including low-light
circuits, among others. A simulation involving different types
of single-phase AC transformers is proposed. The models were
built in two ways, the first using a diode as an electronic
switch, and the second using a thyristor. Different values for
the load were chosen by adopting three values of 30 ohms, 40
ohms, and 50 ohms. An alternating power supply with an RMS
value of 222 volts. Simulation was carried out after modeling to
test the performance of the proposed transformer and its
various modes of operation. Simulation models confirmed and
reinforced the working theories of the proposed structures.
From the results, we can reach the possibility of changing the
voltage and power values using the electronic transformer by
using the frequency of closing and opening the electronic keys
within specific periods according to the proposed model, which
can be represented or modified.
... It is necessary for the specialists to see the behavior of the various unified circuits [26]- [28]. Therefore, researchers focused on all types, including single-phase, and there is also another three-phase type [29]- [31]. ...
One of the problems that need to be solved is the difference in the type of nutrition from the load. The feeding may be from a constant current source such as batteries and solar cells, and there are alternating current sources such as diesel machines, wind energy, and various power plants. All of these sources need electronic power devices that help convert and regulate the control and control of the type of feeding on the one hand and its amount on the other. From here, we show the size of the challenge occupied by electronic power transformers, as they are considered the solution to many problems of transmission, distribution, and feeding systems for different loads. The current study sheds light on one of the types of electronic power systems, which is unified. Choosing and suggesting a set of single-phase unifying circuits to conduct simulations and come up with results that are analyzed to show the function of the non-electronic modulators. In the current simulation, tests were carried out for a group of circuits that need direct current (DC) power, and their available source of supply is an alternating current source. to different departments to access a set of data that enables researchers to conduct appropriate analyzes to perform them, by discussing those results.
... . Equivalent electric circuit of the electromechanical system shown in Figure 10. The dynamic model of a DC motor using controlled voltage power source such as PWM control is widely elaborated in literature [43]- [45]. Therefore, details will not be mentioned here. ...
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... In addition, there are three waveforms of three phase as (13), (14), (15): ...
Many industrial applications require the use of power electronic devices, which in turn help in overcoming the problems of variable load and fluctuations that occur at the end of feeding. The current study emphasizes that the use of different electric power generation systems with industrial applications needs control devices to work on improving the power quality and performance of systems in which there is an imbalance in the voltage or current due to the change of loads or feeding from the source. The present study also presents a model of a transformer widely used in industrial applications and this work includes simulating a three-phase rectifier by MATLAB. There are four cases in this work HWR (uncontrolled and controlled) and FWR (uncontrolled and uncontrolled) with different loads (R, RL & RC) including full wave type AC/DC using six electronic transformer silicon control rectifier (SCRs) once as well as unified half wave using three electronic transformer silicon control rectifier (SCRs). Simulation results include input, output voltage, and current with the waveform.
... Hridya et al. (2018) have introduced a circuit design to control DC motors using a Buck-Boost converter that has an advantage of smaller circuit along with less switching and copper losses. The dynamic model and steady state equivalent circuit of a single-phase AC-DC buck-boost converter fed DC motor with uniform PWM control is presented in Ahmed (2005). ...
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... Mosfet Q is ON (Fig. 2), the charging current in the capacitor C is partially discharged. During the second interval in which the Mosfet Q is switched off (Fig. 3), the polarity of the voltage on the inductor is reversed and the diode is conductive [11,12]. ...
... In the switching ON, the following dynamic is obtained [12]: ...
... In the switching OFF, the following dynamic is obtained [12]: ...
In this paper, the linear state feedback control using LQR controller for a DC/DC converter in the case of negative voltages topology is presented in order to achieve a particular desired behavior. To guarantee a zero steady-state error, we introduce an integral action, which will work out this problem by assuring that the steady-state error will end up to zero. For filtering and state estimation with a low cost and less complexity a state observer is obtained based a Kalman Filter observer. Detailed simulation study is presented to demonstrating the robustness and effectiveness of the proposed control scheme.
... The MATLAB simulation and modeling for steady state and transient analysis of Separately Excited DC motor was done. The performance of the converter is being analyzed, clarified with the PWM control strategy and the DC voltage control [6]. Jaafer Sadiq Jaafer et. ...
... Newer research works are going in this field to bring new techniques too. One of the techniques is active PFC [12]. ...
