Industrial Electronics
Sirous Toofan; Babak Fathipour; Ebrahim Babaei
Abstract
— In this paper, a single switch transformer-less DC-DC converter with continuous input current for photovoltaic applications is proposed. The suggested configuration utilizes a CL1C2D2 structure to achieve a high voltage gain and alleviate voltage pressure on the semiconductor components. This ...
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— In this paper, a single switch transformer-less DC-DC converter with continuous input current for photovoltaic applications is proposed. The suggested configuration utilizes a CL1C2D2 structure to achieve a high voltage gain and alleviate voltage pressure on the semiconductor components. This design enables a significant increase in voltage output with a minimal turns ratio, leading to reduced size, weight, and cost of the converter system. The reduction in turns ratio of the coupled inductor results in lowered voltage stress on the semiconductor elements. Additionally, employing just one power switch in the converter simplifies control and reduces expenses. With its continuous input current, this converter is particularly well-suited for integration in photovoltaic systems. Simulation results conducted using PSCAD/EMTDC software validate the efficacy of the proposed power converter. Furthermore, the maximum power output of the photovoltaic module through an MPPT (Maximum Power Point Tracking) controller under varying irradiance levels is determined, and simulations are executed using PSCAD/EMTDC.
Industrial Electronics
Roya Naderi; Ebrahim Babaei
Abstract
In this paper, a new basic unit is proposed for multilevel inverters. Then, a series connection of the proposed basic unit is used to recommend a new topology for multilevel inverters. To determine the magnitude of dc voltage sources, a new algorithm is presented. For the proposed algorithm, different ...
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In this paper, a new basic unit is proposed for multilevel inverters. Then, a series connection of the proposed basic unit is used to recommend a new topology for multilevel inverters. To determine the magnitude of dc voltage sources, a new algorithm is presented. For the proposed algorithm, different performance parameters such as total voltage rating of switches (TVRS), number of gate drivers, and number of required sources are calculated as a function of the number of output voltage levels and are compared with other topologies. The comparison proves that the proposed cascaded topology requires fewer components and gate driver circuits than most of the other conventional topologies. Moreover, the voltage rating of switches is less than the other topologies which result lower cost and control complexity. Finally, the correctness of the theoretical analysis and the performance of the proposed inverter are verified using the laboratory and simulation results under different scenarios.
Industrial Electronics
Sara Laali; Ebrahim Babaei
Abstract
In this paper, two new developed quasi Z-source inverters (QZSI) based on two new diode-cells are proposed. The proposed inverters are called continuous diode assisted quasi Z-source inverter (CDQAZSI) and discontinuous diode assisted quasi Z-source inverter (DDQAZSI). These inverters are thoroughly ...
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In this paper, two new developed quasi Z-source inverters (QZSI) based on two new diode-cells are proposed. The proposed inverters are called continuous diode assisted quasi Z-source inverter (CDQAZSI) and discontinuous diode assisted quasi Z-source inverter (DDQAZSI). These inverters are thoroughly examined in three modes: two-cell QZSI, three-cell QZSI and n-cell QZSI which is called developed QZSI. Additionally, the equations of the diodes’ voltage and current, capacitors’ voltage stress, boost factor, inductor currents and dc-link current are computed. All equations are given for the proposed generalized topologies. The major advantage of these inverters is the potential of deriving desired boost factor value devoid of extra elements. Furthermore, increasing the quantity of utilized diode-cells in the proposed QZSI reduces the values of dc-link current, inductor current and diode current. Lastly, to verify the performance of the proposed topologies, practicality of the proposed QZSI is authenticated by simulation and experimental results through EMTDC/PSCAD software program and laboratory prototype.
Industrial Electronics
Roya Naderi; Ebrahim Babaei; Mehran Sabahi; Ali Daghigh
Abstract
This work proposes a new multilevel inverter consisting of basic and submultilevel units. The basic unit is made-up of four isolated dc voltage sources, two bidirectional switches and ten unidirectional switches. To increase the number of the output voltage levels, a cascaded architecture based on series ...
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This work proposes a new multilevel inverter consisting of basic and submultilevel units. The basic unit is made-up of four isolated dc voltage sources, two bidirectional switches and ten unidirectional switches. To increase the number of the output voltage levels, a cascaded architecture based on series connection of sub-multilevel is proposed. The proposed inverter utilizes two algorithms to determine the values of dc voltage sources. Number of IGBTs, dc voltage sources, gate driver circuits, variety of dc voltage sources and peak standing voltage on the switches are calculated and their optimization to produce maximum number of levels in output voltage is investigated. To examine advantages of the proposed inverter, the topology is compared with other topologies. The results show superiority of proposed topology over most conventional topologies, in number of circuit components. Finally, to confirm the performance of the proposed multilevel inverter, experimental results of a 25-level inverter prototype are provided.
Industrial Electronics
Taher Ahmadzadeh; Ebrahim Babaei; Mehran Sabahi; Taher Abedinzadeh
Abstract
< p>In power converters, the total harmonic distortion (THD) can be decreased by using two strategies which are filtering and controlling methods. The filtering strategy is indeed costly because of using hardware devices (such as capacitor and inductor). A suitable strategy to control the modern ...
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< p>In power converters, the total harmonic distortion (THD) can be decreased by using two strategies which are filtering and controlling methods. The filtering strategy is indeed costly because of using hardware devices (such as capacitor and inductor). A suitable strategy to control the modern power converters without using the hardware devices is the pulse width modulation (PWM) technique. In this paper, three new PWM control methods based on mathematical equations for various Z-source inverters (ZSIs) are proposed. Controlling the duty cycles of switches is the basic idea of these methods to control the output voltage. The proposed control methods are analyzed under the circumstances of constant input and balanced output voltage (CIBOV) and ripple input and balanced output voltage (RIBOV). The advantages of proposed methods are control of voltage, current and harmonic distortion. Other advantages of these methods are lower value for THD and elimination of low-order harmonics. The correctness operation of the proposed PWM techniques is proved by using the simulation results.