Battery Port Research Articles

A New Three‐Port DC–DC Converter: Analysis, Design, and Verification for Hybrid Energy Systems

ABSTRACTA research study on the three‐port DC–DC converters is done in this article. The proposed converter is a power electronic unit with a low‐voltage, high‐voltage, and battery port. The power of the input ports can be transferred to the output port simultaneously and individually. In this converter, the power can flow bidirectional. In other words, the battery can be charged not only by the low‐voltage port but also by the returned energy from the high‐voltage port. Hence, the proposed converter can operate in step‐up and step‐down modes. Continuous input current, the low voltage stress on semiconductors, and the low count of the devices are other advantages of the converter. These features and the benefits mentioned above make the proposed converter proper for hybrid energy systems. This converter is analyzed in continuous conduction mode, resulting in mathematical equations. To validate these theoretical analyses, a laboratory scale of the converter performs at 50 kHz, 200 W, and 115 V.

Optimized and Sustainable PV Water Pumping System with Three-Port Converter, a Case Study: The Al-Kharijah Oasis

Optimized and Sustainable PV Water Pumping System with Three-Port Converter, a Case Study: The Al-Kharijah Oasis

An Isolated Three-Port Power Converter with 2C3L and 2C2L Resonant Circuits

This study proposed an isolated three-port bidirectional resonant converter that combines 2C3L and 2C2L resonant circuits for application in power dispatching. The proposed converter improves the bidirectional power dispatch capabilities of conventional three-port converters and utilizes different resonant converters to complete the energy charge–discharge through ports of different voltage levels. By modulating the frequency alone, bidirectional power regulation and electrical isolation were achieved among the three ports with different voltage levels. The converter involves the use of resonance techniques to enable the power switch to perform soft switching during bidirectional power transmissions, reducing switching loss and electromagnetic interference. The system control of the circuit was a Texas Instruments TMS320F28335 microcontroller. By simulating a DC grid port with a fixed voltage of 400 V, a vehicle battery port with a variable voltage of 280–403 V, and a battery charging port with a variable voltage of 180–213 V, an experimental platform with a rated output of 3 kW was built to determine the accuracy of the proposed theoretical analysis and design method.

Buck-Boost-Integrated, Dual-Active Bridge-Based Four-Port Interface for Hybrid Energy Systems

A power electronic interface using four ports to interconnect the solar photovoltaic panels, wind generator, battery, and DC microgrid is proposed in this paper. The proposed converter employs a two-winding transformer to interface 380 V of the DC microgrid with all the other three ports, namely, the solar port, wind port, and battery port, which have relatively low nominal voltages. However, the power transfer from solar and wind ports to the battery port bypasses this transformer, thus reducing the potential power losses in the transformer. Furthermore, the maximum and minimum values of the voltage range in which the converter can tap maximum power from solar and wind sources are not constrained by the battery voltage, thus improving the power extraction capability of the multiport converter. The controller for the multiport converter has been developed for extracting the maximum power from renewable sources and to control the charging current of the battery. The simulated response of the converter was studied using the MATLAB/Simulink platform. The simulated response confirms the operation of the converter.

Transformerless High-Gain Three-Port Converter With Low Voltage Stress and Reduced Switches for Standalone PV Systems

This article proposes a high-gain transformerless three-port converter (TPC) for standalone photovoltaic (PV) systems. The TPC is designed and developed based on a dual-inductor high-gain two-port converter by utilizing one of the buffer capacitors to derive the third part for PV input. A hybrid pulse-frequency modulation scheme unified with a pulsewidth modulation control strategy is adopted, which realizes the maximum power point tracking control, load voltage regulation, and bidirectional energy flow at the battery port. The proposed TPC offers the unique advantages of high voltage gain, continuous battery port current, reduced power semiconductors, lower voltage stresses, common ground shared by all the ports, low-cost gate driver, and small size of the rear-end inductor. The working principle, steady-state characteristics, small-signal models, and the control method, including design conditions, are comprehensively analyzed. The correctness of the theoretical analysis is verified by developing a 300-W experimental prototype, which shows that the maximum efficiency is 97.7%.

Three-Port Power Electronic Interface With Decoupled Voltage Regulation and MPPT in Electromagnetic Energy Harvesting Systems

In conventional electromagnetic energy harvesting systems, a two-port ac–dc rectifier is utilized to process the harvested power. However, it is difficult to achieve voltage regulation and maximum-power-point-tracking (MPPT) simultaneously. To resolve this issue, this article proposes a three-port power-electronic-interface (PEI) dedicated to this application. A battery port is introduced to buffer the redundant energy. A bidirectional dc–dc converter is utilized to tightly regulate the load side voltage. To capture the maximum power for the harvester, a simple MPPT method is proposed for this PEI. The power tracking of ac source can be simplified by dealing with the power of the battery port. The regulations of power and output voltage are fully decoupled with different control degree-of-freedoms. Moreover, when the harvester is in idle mode, the load can be powered by the battery via the bidirectional dc–dc converter independently. A 24-mW rated laboratory prototype, which processes the power flow among a 0.6 V, 100 Hz ac source, a 1.2 V battery, and a 3.3 V constant voltage load is developed and tested. The proposed concept is validated by experimental results.

An Integrated Topology of Three-Port DC-DC Converter for PV-Battery Power Systems

This paper introduces an integrated topology of isolated three-port dc-dc converter (TPC) to interface Photovoltaic (PV) and battery for standalone system. To guarantee zero circulating current flow between different ports while permitting bidirectional power flow at the battery port, auxiliary switches are utilized with the active bridges of the proposed TPC topology. In addition, a simple switching scheme based on Pulse Width Modulation (PWM) is proposed for the input ports of the TPC. This action eliminates the need for the phase shift modulation used for conventional isolated TPCs. While the PV port is controlled to track the maximum power point, the battery port is managed to regulate the load voltage. The paper presents the detailed mathematical analysis of the different operation modes of the proposed integrated TPC topology and the estimated control limits during charging and discharging of the battery. Consequently, dynamic limiters for the duty cycle of each port are set. The proposed integrated TPC based PV-battery system is simulated using PSCAD/EMTDC software package to validate the analysis of different operation modes and to assess the dynamic performance of the system. Moreover, experimental results are presented to authenticate different operation modes of the proposed TPC topology and to evaluate the dynamic behavior of the integrated PV-battery system.

An isolated multi-port bidirectional DC-DC converter for EV applications

The challenges in combination of multiple renewable energy sources (RES) in the direction of meet the load requirement is overcome by suitable design of multi-input topology. This paper recommends a three-input DC-DC converter topology with two photovoltaic cells, and one battery providing additional storage. The independent control of input sources enhances the converter reliability during the failure of any one input unit. In addition, the energy storage system is charged by the output port for continual operation. The combinations of switching states and respective four operating scenarios are discussed. The small signal model of the planned multi-port isolated bidirectional DC-DC converter derived and the stability for all possible scenarios are confirmed for open loop system as well the closed loop controller using K-factor method. The proposed converter is simulated with variable input sources using MATLAB / 2015A software. As compared with existing topologies, all ports are controlled and regulated by employing MPPT technique for input renewable energy ports, Constant Current Constant Voltage (CCCV) control scheme for battery port and modified PI regulator for load port. The model is validated by developing a hardware prototype of power rating 500 W, 72 V and its performance efficiency curves are plotted and verified.

A Multiport Bidirectional DC–DC Converter for Hybrid Renewable Energy System Integration

The bidirectional power flow in most of the existing four-port converters is achieved on the battery port located on the low voltage side, i.e., the battery is charged by the energy sources and discharged to the dc link on the high voltage side. The lack of the bidirectional power flow at the dc link prevents them from managing the power at the system level. In this article, a bidirectional four-port dc-dc converter is proposed for the integration of the hybrid renewable energy system to a dc microgrid. The proposed converter uses the least number of devices compared with the existing bidirectional multiport converters. The bidirectional battery and the dc-link ports make it a good candidate for the dc-microgrid application in which the system-level power management is desired. The working principle of the converter is first analyzed, and the power transferred by the transformer and the zero-voltage switching (ZVS) conditions are derived. Then, the converter is designed to meet the requirements of the power rating and soft switching. The proposed converter is used to interface a wind turbine, a photovoltaic panel, a battery bank, and the dc microgrid. The experiments are carried to testify the performance in both steady state and the transient. The steady-state waveforms have validated the power relationship as well as the critical ZVS conditions while maintaining relatively high efficiency. The transient testing results show that the converter can switch from one scenario to another under the different conditions. This article is accompanied by a video demonstrating the converter in the real-time operation.

Dual-Active-Bridge-Based Multiport Converter With Split DC Links

A split dc-link dual-active-bridge (SDLDAB)-based multiport converter (MPC) is proposed in this article. The intended application of the SDLDAB converter is to interface two solar photovoltaic (PV) modules and a battery bank with a dc microgrid. Depending upon the prevailing atmospheric condition, these two solar PV modules can be operated at their maximum power points. This is achieved by maintaining appropriate voltages at the input terminals of the two PV modules. A high-frequency transformer is employed to provide high voltage gain between the dc microgrid and PV as well as battery ports. A direct power flow path is established between the solar PV modules and the battery without involving the transformer. The transformer current is minimized by appropriately modulating the switching sequence of the SDLDAB. Detailed simulation studies are carried out to predict the performance of the system. A laboratory prototype of the SDLDAB having 1-kW power rating is fabricated. The performance of the MPC is validated by carrying out detailed experimental studies on the developed prototype.

Partial Power Conversion and High Voltage Ride-Through Scheme for a PV-Battery Based Multiport Multi-Bus Power Router

With the development of renewable energy technology, distributed power supply mode with multi energy and multi-directional power flow including utility grid, renewable energy and energy storage unit has gradually become a research hotspot. An AC/DC hybrid multi-port power routing (MPPR) system which based on partial power conversion (PPC) of dual DC buses is proposed in this paper. The photovoltaic (PV) port, the battery port and two DC voltage buses form a power router. PV maximum power point tracking (MPPT) and high-voltage ride through (HVRT) of the grid-tied inverter are implemented by the same auxiliary port voltage modulation. The PPC based PV conversion features that only the power determined by voltage difference between PV panel and the series connected DC bus is dealt with, which significantly reduces the loss compared to the full power conversion (FPC) for PV. The detailed control schemes of all converters and energy transmit are given. The simulation and experimental results verify the effectiveness of the proposed scheme.

Analysis and Design of a New Non-Isolated Three-Port Converter With High Voltage Gain for Renewable Energy Applications

This paper proposes a non-isolated three-port converter which integrates the input port, battery port, and load port into one converter for renewable energy applications. The coupled inductor and switched capacitor are used to achieve high voltage gain and three power switches can be utilized to realize the power flows between the sources, the battery, and the load. The energy stored in the leakage inductance is recycled to reduce the voltage stress of the power switch. In addition, various operating stages are analyzed and design considerations are presented. Compared to the relevant converters, the proposed converter can realize power flows and achieve high voltage gain by using few components. Finally, a laboratory prototype of the proposed converter with input port voltage 24 V, battery port voltage 48 V, and output voltage 400 V with 200 W rated power is implemented to validate the feasibility and effectiveness of the theoretical analyses.

A Lossless Passive Snubber Circuit for Three-Port DC–DC Converter

In this article, a soft-switched nonisolated high step-up three-port dc-dc converter is presented for hybrid energy system applications. In the proposed converter, the soft-switching condition is provided for semiconductor elements by a passive lossless snubber without adding any extra active switch or adding any additional semiconductor element in the main power path. The proposed converter is a high integration of single-stage power conversion with multiple input sources and battery port, while the voltage stress of the main switch is kept low. All these benefits have led to high efficiency in comparison to other converter counterparts. Operating principles of the proposed converter are discussed in detail, and design considerations are presented. Finally, experimental verifications are provided to illustrate the feasibility and effectiveness of the proposed converter.

A Performance of a Novel Three Port Converter for Solar PV Storage Systems

This research work is generally emphasize to show and estimate the performance of a new three port converter by connecting a a battery port ,PV port, and also load port all collectively connect in a power system then a original three port converter named bidirectional buck with buck boost converter is projected. The chief advantage of the proposed converter topology is the one-stage power conversion which improve the overall success of the converter. The presentation of the proposed system is simulated in MATLAB and its efficiency based on overall module count, losses and competency is evaluated. Finally to validate the performance of the proposed converter, it is compared with other conservative converters and the evaluation results confirm the dynamic performance of the proposed system. The comparison of various power converters with MPPT technique are made and the simulation result proves the necessity of a suitable converter to be accepted for tracking the highest PowerPoint in solar PV systems.

Topology Analysis and Review of Three-Port DC–DC Converters

In order to realize power flow control among photovoltaic (PV) panel port, battery port, and load port in the distributed photovoltaic power generation system, integrated three-port dc-dc converters (TPCs) are widely adopted. The objective of this article is to provide a comprehensive, comparative, and insightful analysis and overview of these TPCs. First, based on the power transmission and control requirements of the system, five topological structures of three-port dc-dc conversion system (TPCS) composed of two or three two-port dc-dc converters are presented. And the five structures are comparatively analyzed. Second, based on these topological structures, and combing with the basic two-port dc-dc converters, three groups of typical TPCs with different galvanic isolation requirements are derived, respectively, by sharing switches, combining branches, etc., And comprehensive analysis, comparisons, and reviews of these TPCs with different structures of each isolation type are presented with tables and figures. Finally, the comparison results of the three isolation groups are summarized, which leads to a guidance for the selection of TPCs in different applications, and then some suggestions for the future research on TPCs are given.

An Integrated Multiport Dc – Dc Converter for Renewable Energy Applications

As conventional energy sources are steadily depleting n nature due to human activities, renewable energy sources are the need of the hour. Renewable energy source delivers environmental friendly, sustainable power. Due to the intermittent nature of these source, the power produced cannot be used directly by the consumers. So the output power is conditional to meet the grid requirements by using semiconductor devices.In the present system, wind energy output is coupled with back to back power converter and solar energy output with dc to ac converter. The output from the two systems are separately interfaced with the power grid. This has the disadvantages of higher components count, increased cost and inefficient power flow management. The proposed system consists of four ports among which one port is for solar point input, one port is for wind energy input, one bi-directional battery port and an isolated load port. Zero voltage switching is adopted for all main switches in the converter. The integrated four port converter has the advantages of interfacing two sources and controlling them with low cost, compact structure that allow and intelligent power flow management between the household users, the electric distribution grid and the distributed generation units. This converter provides the facilities to combine two or more generation sources. Solar power and wind power are given as input to the two input ports of the converter. The converters use four main switches for this conversion. The output voltage will be a DC voltage. This voltage can be used to derive any DC load or can be converted to AC voltage using inverter to drive an AC load.

A New Soft-Switched Three-Port DC/DC Converter With High Voltage Gain and Reduced Number of Semiconductors for Hybrid Energy Applications

A new partly isolated three-port converter is introduced in this study for hybrid energy applications. Two boost circuits form the main input port and a bidirectional battery port of the converter. Therefore, both of them are of a current-fed type, making the converter more suitable for renewable energy applications. In addition, the boost circuits are benefited from a mutual active clamp circuit. The circuit in cooperation with the leakage inductance of transformers provides soft switching, while employing a few number of semiconductors. Furthermore, on the secondary side, two voltage-doubler rectifiers are merged. As a result, the converter employs less number of components, which participate in all power conversion modes. Since most of the renewable energy sources have a relatively low voltage level, the converter retains high voltage gain. These features have resulted in an efficient and inexpensive converter. A thorough analysis has been made and justified by simulation and experimental results.

An Interleaved Half-Bridge Three-Port Converter With Enhanced Power Transfer Capability Using Three-Leg Rectifier for Renewable Energy Applications

In this paper, an interleaved half-bridge (IHB) three-port converter (TPC) is proposed for a renewable power system. The IHB-TPC is used to interface three power ports: 1) one source port; 2) one battery port; and 3) one isolated load port. The proposed IHB-TPC is derived by integrating two half-bridge TPC modules. A parallel configuration is adopted for the primary side of the two half-bridge modules, while a parallel–series configuration is adopted for the secondary side of the two modules. The power can be transferred from the source and the battery to the load within the whole switching cycle with the proposed IHB-TPC. It means there are no additional conduction losses caused by the circulating current or the free-wheeling operation stage. Hence, the voltage gain can be extended, and the output filter can be reduced. Zero-voltage switching is realized for all the four main switches to reduce the switching losses. Two of the three ports can be tightly regulated by adopting pulsewidth modulation plus phase-shift control, while the third port is left unregulated to maintain power balance for the system. The operation principles and the performances of the proposed converter are analyzed in detail. The experimental results are given to verify the feasibility and the effectiveness of the proposed converter.

Single pole switch leg based multi‐port converter with an energy storage

This study presents a new multi-functional control system for a multi-port energy converter that interfaces one bi-directional battery port, one dc input port, and three output ports. Only one single-leg active switching element (a module type can be used) is employed in the system, and hence the single leg requires digital switching signals for a multi-functional operation to regulate output voltages and to simultaneously manage the battery port. The proposed system has buck-boost conversion capabilities to accommodate wide range, various input sources and output loads. In addition, the single leg requires no dead time due to an integrated impedance network, which will improve the system reliability and performance. Furthermore, the proposed structure can charge a battery even when the input and capacitor voltages are much lower than the battery voltage and hence it significantly improves charging behaviours. The proposed multi-functional control strategy and the converter structure are explained in detail. Then the feasibility and performance of the converter are verified both by computer simulations and experiments based on the Texas Instruments TMS320F28335 digital signal processor.

Three-Port DC/DC Converter With All Ports Current Ripple Cancellation Using Integrated Magnetic Technique

This paper presents a novel integrated magnetic three-port converter (IMTPC) with high power density and all three ports’ current ripple cancellation. The proposed IMTPC can interface one PV port, one bidirectional battery port, and one load port of the PV-battery dc power system. Only two high power magnetic devices are needed in an IMTPC for realizing power conversion, ripple cancellation, and switch driver simultaneously. Three extra capacitors were added to achieve three ports’ current ripple cancellation. Therefore, the port of the IMTPC will always in continuous-conduction mode with “zero current ripple,” thus, size of passive filter can be reduced and accuracy of maximum power point tracking can be improved. Meanwhile, simple driving of the high-side switch can be realized by integrated magnetic winding, which is responsible for MOSFET driver's voltage level shift. The using of the integrated magnetic technique not only performs aforementioned advantages but also shows great potential for reducing the weight and volume of the dc–dc converter. Finally, experimental verifications are given to illustrate the feasibility and effectiveness of the proposed topology and control method.