Series-parallel Topology Research Articles

Research on space power supply utilizing series-parallel techniques

In the realm of space exploration, maintaining a stable and reliable power supply is crucial for the sustained and uninterrupted operation of artificial satellites. However, the unpredictable and often harsh space environment necessitates a redundant design for space power supplies to enhance overall reliability. In light of this, this paper introduces a full-bridge converter employing a series-parallel topology, which augments input voltage redundancy through a combination of serial and parallel connections. Furthermore, a dual-loop Proportional-Integral (PI) control feedback system has been devised, along with a comprehensive analysis of system stability to ensure the optimal performance of both output voltage and current. To validate the efficacy of the series-parallel topology and the feedback system, a complete circuit is constructed, and extensive simulations are carried out under diverse conditions.

Analysis of unified power quality conditioner errors

This article is devoted to error analysis of the unified power quality regulator. In the context of the growing importance of reliable and high-quality power supply, power quality regulators are becoming key devices to ensure the stability of networks and meet the needs of domestic consumers. The paper proposes a comprehensive approach to error analysis of the unified power quality conditioner, the main purpose of which is to compensate for the impact of rapidly changing loads on power quality. At the same time, indicators of general harmonic distortion of the quality of electricity are analyzed, and factors such as the magnitude and duration of loads are also taken into account. A large part of the article is devoted to the study of the sources of errors in unified power quality conditioner. A comparison of the parallel-serial and series-parallel topologies of unified power quality conditioner is performed. The influence of the unified power quality conditioner control algorithm on the formation of errors of each topology is analyzed. Using Matlab/Simulink computer simulation tools, the article proposes a framework for error quantification, which allows accurate estimation of errors at various stages of unified power quality conditioner operation. This framework covers the Fourier series transformation of voltage and power for comprehensive estimation of error magnitudes. To confirm the effectiveness of the proposed error analysis and compensation strategies, the article presents graphs of simulation results in the time and frequency domains. Active and reactive power generation errors and voltage setpoint errors are described. These findings emphasize the ability of unified power quality conditioner to improve the quality of electricity, despite measurement errors. The main results include the analysis of deviations of voltage quality indicators, the establishment of a connection between compensation errors and deficiencies in the functioning of the system, as well as the development of recommendations for improving the efficiency of compensation devices.

Comparative Analysis of SS, SP, PP and PS Topologies for Magnetic Coupled Wireless Power Transfer System Composed of the Negative Resistor

In recent years, the concept of the negative resistor (NR) has been proposed and applied in the magnetic coupled wireless power transfer (MC-WPT) system to improve the stability of power transfer. However, it remains a fundamental challenge to find the characteristic differences and applications of the four basic NR-based MC-WPT topologies. In this paper, the circuit models of the four basic NR-based MC-WPT topologies: series-series (SS), series-parallel (SP), parallel-parallel (PP), and parallel-series (PS) are established, and their characteristics are analyzed and compared by using circuit theory, which enables engineers to determine and select topologies to suit different applications and requirements. Theoretical analysis shows that the compensation methods of the transmitter and receiver of the NR-based MC-WPT system would affect the operating frequency and output characteristics of the system. Moreover, by comparative analysis, the conditions and applicable ranges for a stable output of different topologies were provided. Finally, the experimental prototypes are set up by using the power electronic inverter and operational amplifier, and the voltage gain ratios of the four basic NR-based WPT topologies under the variations of transfer distance and load are observed. The experimental results validate the correctness of the theoretical analysis.

A Novel MPPT-Based Lithium-Ion Battery Solar Charger for Operation under Fluctuating Irradiance Conditions

Fluctuant irradiance conditions constitute a challenge in front of a proper battery charging process, when originated from a PhotoVoltaic Array (PVA). The behavior of the PVA under such conditions (i.e., reflected by a disturbed PV characteristic curve) increases the complexity of the total available power’s extraction process. This inconvenient fact yields eventually to a decreased overall efficiency of PV systems, especially with the presence of imprecise power-electronics involved circuits. Accordingly, the purpose of this paper is to design a complete battery solar charger, with Maximum Power Point Tracking ability, emerged from a PVA of 1.918 kWp, arranged in Series-Parallel topology. The targeted battery is of Lithium-Ion (Li-I) type, with 24 VDC operating voltage and 150 Ah rated current. The design began by configuring an interleaved synchronous DC-DC converter to produce a desired voltage level, with low inductor ripple current and low output ripple voltage. The DC-DC converter is in turns condemned by a modified Perturb and Observe (P&O) algorithm, to ensure efficient maximum power tracking. Progressively, the design encountered a layout of the bi-directional DC-DC converter to ensure safe current charging values for the battery. Under the same manner, the role of the bi-directional converter was to plug the battery out of the system, in case when the Depth of Discharge (DoD) is below 25%, thus sustaining the life span of the battery. The entire setup of the proposed sub-systems then leads to the relatively fastest, safest, and most reliable battery charging process. Results show an effectiveness (in terms of PV power tracking) ranging from 87% to 100% under four swiftly changing irradiance conditions. Moreover, this paper suggested the design’s future industrialization process, leading to an effective PV solar charger prototype.

Electrical–thermal–fluidic coupling Li-ion battery pack consistency study

The thermal effect of lithium (Li)-ion batteries affects its performance and service life and threatens its safety. Therefore, a new tree-shaped channel heat sink was developed for cooling Li-ion battery packs and compared with fractal and serpentine channel heat sinks. Moreover, the electrical–thermal–fluidic multi-physics simulation was implemented based on the equivalent circuit model. The temperature distribution effect on the battery pack's consistency was investigated. Different circuits were established through various series–parallel topologies, and the battery pack's discharging and temperature characteristics were examined when the cells' initial parameters were different. The results demonstrated that the new tree-shaped channel heat sink offered effective heat dissipation and small flow resistance. The decreasing temperature difference enhanced the current consistency, while the decreasing temperature rise reduced the voltage consistency. The series or parallel connection between the battery modules slightly affected the battery pack's discharging and temperature characteristics. Within the module, a reduction in the number of batteries in series or augmentation in the parallel branches reduced the battery consistency and increased the battery pack's average temperature rise and temperature difference. The battery consistency in the parallel-first topology module was better than that in the series-first topology module under the same number of parallel branches. These results are helpful for the battery pack consistency studies.

The Combined Effect of Current Boosting and Power Loss on Photovoltaic Arrays under Partial Shading Conditions

This study proposes a novel technique for improving the performance of photovoltaic (PV) arrays under Partial Shading Conditions (PSCs). A 4×4 solar PV array with 16 panels was considered. Bridge-Linked (BL), Total Cross-Tied (TCT), Honey Comp (HC), One Cross-Link (OCL), and Two Cross-Link (TCL) were among the topologies of interest. First, the combined effect of connecting switches and partial shading on the PV array was studied. Then, the power loss/gain caused by reconfiguring the PV array structure from Series-Parallel (SP) to other schemes was investigated. Finally, a method of boosting current into the PV array is proposed to reduce PSCs-related power losses in the connecting switches. The results show that the number of connecting switches in the topology plays an important role in determining power gain or loss at different partial shading levels. TCT and HC outperformed the others in terms of power improvement when PSCs were considered without current boosting. This is true for different levels of solar irradiation exposure. The SP topology is optimal when the solar irradiation level is greater than 900W/m2 or less than 200W/m2. TCT outperformed the others when the current was boosted in the PV array, with a power improvement of 108%, for certain PSCs.

Improving Wireless Power Transfer Efficiency Considering Rectifier Input Impedance and Load Quality Factor

This paper presents a method to maximize power transfer efficiency (PTE) in wireless power transfer (WPT) systems with low-quality factors merely based on tuning the receiver-side components. The paper also suggests an algorithm to find the optimum components values considering the effect of input impedance of receiver-side rectifier at high-frequency (MHz) applications such as portable electronic devices. Existing methods often consider the input impedance of the full-bridge rectifier as a pure resistance at low frequencies. However, at high frequencies, the complex impedance of the rectifier should be taken into account since it impacts on the components optimum values to maximize PTE. Despite conventional maximizing PTE methods for series-series and series-parallel topologies, this paper shows that a series-parallel WPT system with low load quality factor requires adjusting the resonant capacitor in addition to resistive load. The validity of the proposed method is verified based on numerical simulations and experiment tests using a 100 mW cm-scale prototype of a resonant inductive link at 6.78 MHz with varying distance between coils. The test results show a PTE improvement up to 40% in a series-parallel WPT compared with the methods that only tune the load equivalent resistance.

Synthesis of a Class of Reciprocal -Ports and a Highly Singular Construction

We give a canonical synthesis of those reciprocal <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${n}$ </tex-math></inline-formula> -ports which are at the same time antireciprocal as well, using only as many components as the number of independent nonzero entries in the describing hybrid matrix, and using series-parallel topology. Examining the smallest non-series-parallel topology we obtain a 2-port which behaves as two nullators or two norators at some extreme values. Mathematically its level of singularity is the same as that of the classical example of Carlin and Youla but they used a 3-port circulator while we use reciprocal devices only.

Model of fractional-order resonant wireless power transfer system for optimal output

Abstract Wireless Power Transfer (WPT) technology has recently gained popularity in applications and research topics. It enables the transfer of electrical energy from a source to a load without connecting wires physically. The WPT system is commonly studied classically using integer order capacitors and inductors. Nonetheless, such integer order based systems have drawbacks, such as low output power, poor transmission efficiency and sensitivity to parameter variations. This paper proposes a fractional order resonant WPT circuit whereby both the transmitting and receiving ends are composed of a fractional capacitor and inductor to overcome such problems. In this paper, the overall performance is studied based on its output power and efficiency considering a series-parallel topology. The effect of fractional order in fractal elements will be analyzed to observe the optimal combination of components to achieve the maximum output power with higher efficiency. Through a comparative analysis of the results, several combinations of circuit parameters can provide a theoretical understanding for implementing an experimental system.

Optimization of Solar Panel Deployment Using Machine Learning

In this work, we proposed a mechanism for topology reconfiguration or optimization of photovoltaic (PV) arrays using machine learning-assisted techniques. The study takes into concern several topologies that includes series parallel topology, parallel topology, bridge link topology, honeycomb topology, and total cross tied. The artificial neural network-based topology reconfiguration strategy allows for optimal working conditions for PV arrays. With this, machine learning-assisted topology reconfiguration or optimal solar panel deployment enables the proposed mechanism to achieve higher degree of testing accuracy precision, recall, and f-measure under standard ideal condition.

Performance Analysis of Diode-Assisted Switched LC qZSI Network-Based Multioutput Series-Parallel Topologies in Microgrid Application

In this paper, two (series and parallel versions) quasi Z source inverter (qZSI)-based multioutput series-parallel topologies capable of supplying multiple three-phase AC and single boost DC outputs simultaneously are presented. The proposed parallel version topology can supply n number of AC outputs along with one boost DC with constant voltage and variable current. Similarly, the series version topology can give n number of AC including one boost DC output with constant current and variable voltage. The outputs of the proposed topologies can feed directly to DC/AC microgrids and multiple residential loads simultaneously without using any extra adapter/regulator and thereby avoiding local power conversion to meet the load demand. A hybrid pulse width modulation technique with constant frequency is used to operate the proposed topologies. The performance of the proposed topologies is verified by developing the prototypes of 2.18 kW (for parallel version) and 2.02 kW (for series version) for two three-phase AC outputs and one boost DC output. The developed prototypes show measured efficiency of 90.01% for the parallel and 89.95% for the series version topology.

Geometrical parameter optimization of planner square-shaped printed spiral coil for efficient wireless power transfer system to biomedical implant application

In this paper, the wireless recharging of pacemaker's battery for biomedical implant is considered. Planner square-shaped printed spiral coils (PSCs) are selected as primary (Tx) and secondary (Rx) coil for wireless power transfer (WPT) system. FEM based simulation method is used to optimize the geometrical parameters of square-shaped PSCs. The receiving coil is embedded inside the biomedical implant. The coil track width (w), pitch(s), thickness (t), number of turns(N1,N2) and outer diameter (Dout) of square-shape PCS's are the key parameters for higher coupling coefficient and quality factors. Using magnetic resonance coupling (MRC) based on Series-Parallel (SP) topology; experiments are carried out in an analytical, simulation, and physical environment for four operating frequencies: 300 kHz, 800 kHz, 6.78 MHz, and 13.56 MHz. Efficiency obtained by analytical and simulation method is higher with frequency. The optimum frequency for recharging the pacemaker battery is 6.78 MHz, which provides an efficiency of 85.51% at 100Ω load and is very close to the maximum theoretical efficiency. Voltage gain obtained by physical method is in close approximation with analytical and simulation methods.

Co-Simulation Platform for Simulating Heavy Mobile Machinery With Hydraulic Actuators and Various Hybrid Electric Powertrains

Computer simulations are important tools for evaluating hybrid electric powertrain concepts. In heavy mobile machinery, the powertrain undergoes traction and often hydraulic loads. The dynamic loads on hydraulic actuators of heavy mobile machinery can be studied using detailed physics-based simulation models. The effect of coupling hydraulic actuators to various configurations of hybrid electric powertrains is studied using a co-simulation approach in this study. The case example of a tractor modeled using multibody dynamic approach combined with four powertrain configurations with different topology and hydraulic actuator coupling is investigated. A farm tractor was simulated in a virtual environment with deformable terrain in a soil digging and dumping work cycle. The coupling of hydraulics to the electric energy source in a series-parallel topology achieved fuel savings of 10.5% and total energy savings of 12.3%. The presented modeling method can be used to simulate various heavy mobile machinery to evaluate hybrid electric powertrains using work cycles created by human operators.

Overview of the main powertrain architectures for hybrid and electric vehicles

The research for alternative solutions to assist the propulsion, fuel converters and energy storage systems (ESS) in vehicular applications has become the focus of many institutions and mainly in the automotive industry, aiming to reduce the impacts caused by the emission of gases in the exhaust pipe and to improve energy efficiency in the worldwide vehicle fleet. Hybrid Electric Vehicles (HEV) and Electric Vehicles (EV) are currently a reality and meet this requirement to build a greener and less polluting society. In this context, this paper describes the operational characteristics of the different powertrain architectures employed in hybrid electric vehicles, including series, parallel and series-parallel topologies, as well as battery-powered and fuel cell electric vehicles. Finally, some of the elementary issues facing these advanced vehicular technologies, including the challenges for market penetration are highlighted.

A Multiport Power Electronics Converter for Hybrid Traction Applications

Environmental concerns and energy efficiency have been driving the transportation innovation in the past decades. In this framework, hybrid city transport has been receiving the attention of the industry. The challenges for this application are the required high-power density, lower maintenance cost and the high-temperature environment due to the integration with the internal combustion engine. A multiport converter is proposed to realise the requirements of the automotive industry to achieve greater performance in driveline electrification. The platform suggests the combination of previously discrete power electronics converter modules into one physical package commonising parts such as the microcontroller, heatsink and busbars. This paper provides an overview of design considerations for engine start-stop within a series-parallel topology and how it is achieved using the multiport converter. Finally, a comparison between the multiport and discrete converter approach is made compared and findings presented, highlighting the advantages of the integrated solution.

Reduced partial shading effect in multiple PV array configuration model using MPPT based enhanced particle swarm optimization technique

The depletion of energy resources are increased day by day, which is the main environmental problem for today's world. Recent development uses solar energy because the photovoltaic cost is less. Nowadays, solar systems reduce the global energy demand using various novel techniques and configurations. However, multiple peaks in the power characteristics curve develop the partial shading effect in the PV array. The main objective of this proposed method is to reduce the multiple peaks in the output power characteristics and reduce the drawback in array configurations since it increases the overall system efficiency. The conventional method uses series, parallel, series to parallel, Total-Cross-Tied, Sudoku pattern and bridge linked PV configurations. All these technique effectively carried out the partial shading of PV array. In this proposed model, the reduced partial shading effect is configured through multiple PV array configurations like series, parallel, TCT, bridge linked and series-parallel. Here with enhanced PSO based MPPT technique is used to optimize the power shading effect in the PV array configurations. Here the PV cells are arranged by PV configuration model and the PV array is developed with various irradiances for knowing the effect of partial shades. The Maximum Power Point Tracking System is used to reduce the multiple peaks in the power curve with enhanced PSO technique. Based on the multiple PV array configurations, the power, voltage and current is measured and the maximum power point is tracked to provide the maximum power range. This PV array configuration is optimized by artificial bee colony algorithm. Here in the MPPT, the PI controller utilizes the controller block and PSO is used to optimize the global and local best possible values. By comparing with the conventional method, the proposed method achieves the result of output voltage, current, power and MPP power peaks. As per the experimental result, the series and series-parallel topology achieves the result upto 90% of circuitry than existing approach. The overall system is done by using MATLAB/Simulink with the adaptation of 2018a.

Improving performance of photovoltaic panel by reconfigurability in partial shading condition

A photovoltaic (PV) panel operating in partial shading condition results in lowering its power efficiency. In a worst-case scenario, it can create a hotspot that can eventually cause a fire hazard. To address this issue, bypass diodes are connected across a group of PV cells having series-parallel (SP) configuration. Owing to the placement bypass diodes in the PV panel, it can circumvent unshaded PV cells. Hence, topologies such as total cross-tied (TCT), bridge link (BL), and honeycomb (HC) for PV panels are proposed besides SP to reduce the effect of partial shading. Each configuration demonstrated advantages over SP topology. However, many of these configurations lack a mechanism to isolate PV cells that are affected due to the hotspot. Recently developed complementary metal oxide semiconductor (CMOS)-embedded PV panel has been shown to offer many other benefits besides effectively dealing with shading conditions. We are comparing the performance of CMOS-embedded PV panel under various partial shading conditions with PV panel with fixed configuration topologies, such as SP, TCT, BL, and HC. SPICE-based equivalent PV modeling technique is used in this research to compare the maximum power generated in different topologies under changing partial shading conditions. Results show that CMOS-embedded PV panels are more efficient in coping with partial shading conditions compared to any other contemporary fixed topologies.

Time-Domain Modeling and Analysis of Switched-Capacitor Converters

This article proposes time-domain modeling and analysis of switched-capacitor converters (SCCs) by homogenizing the state-space model, resulting in a closed-form expression of the output voltage as a function of time without requiring discretization and subsequent numerical solution. The proposed technique facilitates obtaining the steady-state output voltage at any arbitrary time within a period, rather than at one discrete time at the beginning or end of the clock period. Circuit-level simulations for various SCC topologies, viz. , series–parallel (SP), ladder (LD), Fibonacci (FB), and Dickson (DK), show excellent agreement of the time-domain behavior as well as the equivalent resistance of the converter with the proposed technique. The proposed technique gives more than an order-of-magnitude improvement in simulation time. Experimental data for SP and LD topologies have been used to validate the accuracy of the proposed technique.

Strategy of Topology Selection Based on Quasi-Duality Between Series–Series and Series–Parallel Topologies of Resonant Inductive Coupling Wireless Power Transfer Systems

Series–series (SS) and series–parallel (SP) topologies are widely used in resonant inductive coupling wireless power transfer systems for various applications. However, the selection of an appropriate topology to achieve higher output power or higher efficiency is typically difficult because design optimization of the circuit parameters (e.g., characteristic impedance, load resistance, and mutual inductance) for each topology is generally separately discussed using different equivalent circuits with multiple resonance modes. Therefore, the purpose of this study involves proposing a simple strategy to select an appropriate topology. The proposed strategy is based on quasi-duality between the SS and SP topologies that are elucidated from the novel equivalent circuits derived using Lagrangian dynamics. Based on the quasi-duality, the output power and efficiency of the SP topology are calculated via the equivalent circuit of SS topology. Thus, the quasi-duality offers a simple comparison between the SS and SP topologies. The proposed strategy selects an appropriate topology by comparing only the equivalent ac load resistance, which is the ac resistance including the rectifying circuit and the load resistance, the characteristic impedance, and the ac load resistance that achieves the maximum efficiency or maximum output power of the SS topology. Experiments verify the appropriateness and effectiveness of the proposed strategy.

Efficiency investigation of SS and SP compensation topologies for wireless power transfer

&lt;span&gt;Wireless power transfer (WPT) using inductive and resonant coupling has been widely explored in recent years for ease and safety over conventional cable charging systems. The efficiency of WPT systems is reducing drastically due to an increase in air-gaps and misalignment between transmitter (Tx) and receiver (Rx). Many circuit topologies have been analyzed to improve the efficiency of WPT system based on symmetrical coils. However, the circuit topologies have not been studied widely for unsymmetrical coils. This paper presents the investigation of two fundamental topologies i.e. Series-Series (SS) and Series-Parallel (SP) for unsymmetrical coils as well as symmetrical coils. Theoretical analysis of both the compensation topologies have been accomplished, then modeling of both the topologies have been done using two different combination of circular coils. In first case, two similar size coils have been designed and in second case transmitter coil of higher dimensions than receiver coil is designed. The efficiency of the system has been analyzed at multiple distances in both cases by integrating coil structure with the circuit. The overall result show that when Tx is bigger than Rx, the SP topology gives better efficiency than SS counterpart.&lt;/span&gt;