Single-phase Full-bridge Inverter Research Articles

Development of Improved Low-leakage Current H6 Single-Phase Full-Bridge Inverter Topology

Objective: To minimize leakage current in non-isolated photovoltaic grid connected inverters. Methods: The circuit design integrates extra switches and modifies the switch drive signals at the midpoint of the DC bus voltage, altering the common-mode current path. Findings: The proposed topology exhibits significant potential for widespread adoption, finding practical applications in diverse industrial settings as well as in residential use. Novelty: The suggested method implies that the topology presents distinctive or beneficial characteristics in contrast to current solutions, rendering it especially promising for a range of industrial and residential applications. This novelty may arise from enhancements in efficiency, cost-effectiveness, scalability, versatility, or other favorable attributes that distinguish it from traditional approaches. Moreover, Simulation outcomes distinctly demonstrate a noteworthy decrease in leakage current within the refined topology when contrasted with both the H5 topology and the High Efficient and Reliable Inverter Concept (HERIC) topology. This compelling evidence affirms the effectiveness of the proposed configuration in proficiently mitigating leakage current. Keywords: Photovoltaic, Common Mode Voltage, Leakage Current, Grid Connected Inverter

Analysis and Compensation of Dead Time Harmonics Based on Time Compensation Strategy in the Single-Phase Full-Bridge Inverters

Analysis and Compensation of Dead Time Harmonics Based on Time Compensation Strategy in the Single-Phase Full-Bridge Inverters

Loss and efficiency comparisons of single-phase full-bridge inverters according to switch structures

Loss and efficiency comparisons of single-phase full-bridge inverters according to switch structures

A single-phase full-bridge soft-switching inverter circuit with an auxiliary resonant circuit

A new topological structure is proposed in this article for the traditional single-phase full-bridge inverter circuit by adding an auxiliary synchronizing resonant circuit. Without extra switching transistors, the complexity of the control circuit is simplified while enabling zero voltage switching (ZVS) functionality. The significance of this proposed topology is that the switching transistors of all bridge arms are sharing one common synchronizing unit which is constructed with an absorbing inductor and capacitor. In this way, the added-on components can be substantially reduced for the main switching transistor circuit. By utilizing a big-volume capacitor as the constant voltage source, the sourceless energy feedback unit can minimize the switching losses. In the meantime, the proportional-resonant feedback circuit can modify the sinusoidal pulse width modulation (SPWM) duty ratio to stabilize the output current. In the PSIM power electronic simulation software environment, the operation of the soft-switching inverter circuit is analyzed to demonstrate our proposed topology can reduce the on-off switching losses as expected for the switching transistors of the soft-switching inverter circuit.

The Concentrator for Single-Phase Inverters with Three-Phase Output Using Magnetically Coupled Reactors

This paper presents a passive concentrator for single-phase inverters with a three-phase output, which uses magnetically coupled reactors. Due to the development of renewable energy systems, the proposed systems may enable the easier integration of converters in the form of inverters with the power system. Two variants of cooperation of the concentrator with single-phase voltage inverters were considered. The first variant proposed a system topology in which three single-phase full-bridge inverters were connected to the concentrator, while the other variant proposed six half-bridge inverters. A control system of the inverters that does not use PWM was developed. A common star point was created for the supply voltages in the form of a capacitive divider covering all the inverters. An analysis of the concentrator system was presented, taking into account the cooperation with inverters. The overall power of the TDSλ system was defined and the relationship for its determination was given. Simulation studies were described, presenting the obtained voltage and current waveforms. The impact of changing the supply voltage of the inverters on the operation of the concentrator and the shape of the output voltages was assessed. The proposed systems allow you to connect 3 or 6 single-phase inverters. The use of magnetically coupled reactors enables the use of a magnetic system of lower power and size. The described concentrators enable the generation of multi-level three-phase output voltage with a low THD content.

Robust Cascade MRAC for a Hybrid Grid-Connected Renewable Energy System

Hybrid grid-connected renewable energy systems have gained significant importance in sustainably responding to an increased electrical energy demand. These are time-varying nonlinear dynamical plants, where the value of their parameters depends on changing weather conditions and the alternating grid voltage with randomly fluctuating amplitude. This paper proposes a robust cascade MRAC for nonlinear plants representing a class of these systems, which includes n renewable energy converts and a DC/AC single-phase full bridge inverter. The proposal reduces commissioning time by avoiding linearization and knowledge of the plant parameters. Moreover, it includes specific formulas for tuning the controller parameters that decrease their adjustments based on trial and error. Finally, it uses a direct adaptive method with adaptive laws having σθ modification and an inner loop at least five times faster than the outer loop. The proposition validation includes the theoretical stability proof based on the Lyapunov stability method and Barbalat’s Lemma. Furthermore, it presents comparative simulation results with quoted cascade PI controllers for a monophasic system, including two renewable energy sources and injection. Both techniques effectively track setpoint changes of the energy sources’ currents and direct current bus voltage, showing the proposal similar or reduced ripple. At the same time, both ensure robustness against decreased photovoltage panels irradiance, increased fuel cells voltage, and grid voltage amplitude random fluctuations. However, the proposal does these things while avoiding prior linearization and unknowing the plant parameters.

A Differential Compensated Air Coil Current Sensor for Switching Current Measurement of Power Devices

Accurate current measurement is the basis for power devices to achieve switching characteristics evaluation, real-time control, reliability diagnosis, life prediction, etc. With the rapid development of power semiconductor device technology, requirements for current measurement are getting more and more stringent. The printed circuit board Rogowski coil current sensor (PCB RCCS) is a potential competitor, which has excellent bandwidth and integrability. However, the contradiction of the droop and drift phenomena as one of the main challenges restricts the employ of the RCCS in switching current measurements. In this paper, a differential compensation scheme that can solve these problems simultaneously with a lower error and cost is proposed. And the sensitivity and bandwidth of this sensor can be accurately obtained. Finally, a buck and single-phase full-bridge inverter experimental platform are built to verify the effectiveness of the PCB RCCS in the measurement of the switching current and inductor current, respectively.

Design of single cycle current control method based on single-phase full bridge inverter circuit

To achieve accurate control of the large inductive load, a single-phase full bridge inverter circuit topology with a simple structure is proposed. The current control on inductive load is realized by using the single-cycle control method, and the size and direction of the current can be adjusted at any time. The loading part is equivalent to the coil and resistance, the control principle of the circuit is analyzed, and the calculation formula of the duty cycle is calculated. The simulation results show that the designed circuit structure can control the current with a large inductive load

Analysis and design of control systems via parameter‐based approach

Analysis and design of control systems via parameter‐based approach

Design of a robust adaptive self-tuning regulator controller on single-phase full-bridge grid-connected inverter

Design of a robust adaptive self-tuning regulator controller on single-phase full-bridge grid-connected inverter

Improved tunicate swarm search-based MPPT for photovoltaic on a "grid-connected" inverter system.

Photovoltaic (PV) systems are broadly utilized, especially for remote electrification. It is easier for installation and is free of greenhouse gases, so the impacts on the environment are reduced. The temperature and irradiance change during the day, and the circumstances are more dynamic on cloudy days. Hence, attaining maximum power under some environmental conditions is complex and also requires individual techniques for tracking the maximum available power. These approaches are named maximum power point tracking (MPPT) methods. These are designed through power electronic converters, which supply the PV power to the load. In recent years, meta-heuristic-based algorithms have emerged because of their local optima avoidance ability and flexibility. However, the maximum power point (MPP) will not be tracked efficiently due to the constraint factors between some circuit parameters. This limitation has to be solved in this study. Here, MPPT constraint conditions of the PV system with an inverter are found by analyzing its integrated mathematical model. The MPP of a PV system is tracked by diverse techniques. Though these approaches differ in complexity, effectiveness, and convergence speed, cost and sensors are required. With the effect of these challenges, the main intention of this paper is to design and develop a new modified MPPT algorithm for enhancing the efficiency of the power grid connected with a DC-AC single-phase full-bridge inverter and a proportional integral derivative (PID) controller. Here, the parameters of the PID controller are tuned or optimized by the newly improved meta-heuristic algorithm termed modified tunicate swarm algorithm with new condition (MTSA-NC) thus maximizing the energy extraction of the PV system. The search process for newly improved MTSA-NC works well to adapt the MPPT to cope with a "grid-connected" inverter by attaining a faster convergence rate. Here, MTSA-NC is adopted by introducing the fitness-based solutions for updating the swarm behavior of tunicates to maximize the energy efficiency of "grid-connected" inverter systems for PV arrays. In MTSA-NC, the optimal fitness value is known as a food source, which is used for determining the solution updating. Finally, the experimental tests validate the success of the designed scheme in a PV system during uniform irradiance and partial shading conditions.

Single phase grid interconnected high gain boost converter with soft switching capability

<div align="left"><span>The grid interconnected application systems require high voltage levels which leads to an efficiency reduction. To overcome this, a new high gain boost converter in association with buffer capacitor, passive clamp recovery circuit to restore leakage energy in coupled inductor is presented. The magnetic field of the linked inductor stores the energy obtained from the supply. The energy is transmitted to the connected load for consumption in further operating modes. A passive clamp network recovers the energy that is stored in the leakage inductance, enhances the gain of voltage, and improves overall system efficiency. The essential feature of this converter is that, high duty ratios are not required to achieve higher voltage gain, hence the reverse recovery problem of the diode is prevented. Moreover, a passive clamp network decreases the voltage stress of the switch, thus a minimum rating switch is used, as a result, the system's total efficiency improves. This converter output is fed as input to a single-phase full-bridge inverter and also synchronized to a single-phase grid. The performance and powers injected are analyzed by connecting a resistive load. </span></div>

Generalised predictive controller (GPC) design on single‐phase full‐bridge inverter with a novel identification method

The design of an on-line generalised predictive control (GPC) technique with a novel identification method is presented in this paper for a single-phase full-bridge inverter in the presence of different disturbances. The controller uses system discrete-time model to reach the control variables with a prediction over these values, followed by computing a cost function for control aims. However, in this controller, the need for the mathematical model of the system is removed since the black-box identification strategy is used. Moreover, GPC structure has many advantages including low computational complexity, systematic design procedure, and fixed switching frequency that makes it a good alternative for practical applications. Various disturbances can have a negative impact on a DC–AC inverter; thus, considering robust dynamics and ease of implantation, the GPC scheme is used along with an improved exponential regressive least square identification algorithm as an adaptive strategy in the controller. Moreover, the prediction horizons of this controller have been increased, resulting in its low steady-state error and better performance. Furthermore, harmonics in the sinusoidal signal can decrease the total efficiency of the system; thus, an LC filter is used to reduce the level of total harmonic distortion. However, the stability of the filter is the most challenging issue in designing a suitable controller. Finally, the strength of the current controller is verified using experimental and simulations results.

High efficient and high gain boost converter with soft switching capability connected to grid using dq axis current control

Renewable sources like solar PV arrays are generally operated at low voltages due to safety issues. For applications such as grid connected systems, it requires boosting to high voltage which leads to reduction in efficiency. To solve this, a new high gain and efficient boost converter which is a combination of buffer capacitor, passive clamp recovery circuit to restore leakage energy in coupled inductor is presented. The magnetic field of the linked inductor stores the energy obtained from the supply. A passive clamp network recovers the energy that is stored in the leakage inductance, enhances the gain of voltage and improves overall system efficiency. High duty ratios are not essential to achieve higher voltage gain, hence the reverse recovery problem of diode is prevented. Moreover, passive clamp network decreases the voltage stress of switch, thus a minimum rating switch be used, as a result, the system's total efficiency improves. This converter output is fed as input to a single phase full bridge inverter and also synchronized to a single phase grid by using d-q axis current controller. The performance and powers injected are analyzed by connecting a resistive load.

FPGA-Based Single-Phase PV Inverter Using Unipolar and Bipolar SPWM Control Techniques

The study presents circuitry modeling and methodology to integrate solar photovoltaic (PV) energy with grid (AC) sources to supplement household appliances during a power cut-off or restricted supply period and alternating charge deep cycle batteries. This paper discusses an FPGA-based Sinusoidal Pulse Width Modulation (SPWM) generator as a control mechanism for a PV/Battery full-bridge inverter. The inverter's efficacy is expressed as the Total Harmonic Distortion (THD) ratio, which must be as low as possible. Various schemes are proposed to reduce THD to generate a more sinusoidal output wave. SPWM is mostly used in industrial inverters. Two SPWM techniques, Bipolar and unipolar, are compared under a variety of Modulation Index (MI) conditions and Carrier Frequency (fc) to analyze the best performance of the full-bridge inverter with less (THD) and smoother output sinewave. The present paper discusses the results of a simulation for a single-phase full-bridge inverter employing bipolar and unipolar SPWM techniques. The output waveform demonstrates that the Unipolar SPWM technique produces less Total harmonic Distortion than the Bipolar method, with THD 45% lower. ISE 14.7 and Matlab 2019 are used to present, simulate SPWM generating code, and implement the design on a field-programmable gate array (FPGA), which acts as a controller for the Mosfet gates in the full-bridge inverter to constitute a sine wave without changing any hardware configuration in the circuit design. The system implementation of SPWM Pulse generation has been validated on Xilinx Spartan 6 FPGA (XC6SLX45) board using VHDL code. The final test on the system design for the SPWM generation program, after synthesis and compilation were finalized and verified on a prototype system.

Hardware-in-the-loop simulation of inverter power supply controller based on StarSim and DSP

Aiming at the contradiction between the requirements for rapid development and verification of inverter power supply controller products and the actual construction of real inverter power supply circuit topology, this paper proposes to build a semi-physical simulation platform based on StarSim and DSP. This paper takes the single-phase full-bridge inverter power supply as an example, use Shanghai ModelingTech company’s StarSim real-time simulator as the hardware platform, establish the circuit model in Matlab/Simulink and select NI PXIe-7846R board to run circuit extensions, and use TMS320F28335 as controller of the phase inverter power supply, based on StarSim HIL host computer program to load the model, configure the IO, and test and verify. The experimental results show that the semi-physical test platform has high accuracy and feasibility, shortens the development cycle of the controller, and greatly reduces the development cost of the controller.

Research on Real-time Simulation of Power Electronic Circuits Based on Simscape

In order to realize hardware-in-the-loop simulation of commonly used power electronic circuits, a method of joint simulation using Simcape and field programmable gate array (FPGA) is proposed. This article adopts a switch modeling method suitable for high-frequency characteristics, namely the switch function method. It effectively solves the problem of rigidity non-convergence in the modeling of the binary resistance method, as well as the transient error caused by the binary LC method when the system state is switched with the increase of the switching frequency, which reduces the simulation accuracy. Taking the single-phase full-bridge inverter circuit as an example, a Simscape model based on the state-space averaging method was established, and the HDL code was automatically generated using the Simscape HDL Workflow Advisor tool, and the hardware-in-the-loop simulation was completed with FPGA. Finally, the simulation results with Simulink comparison verify the effectiveness and feasibility of the method.

Single phase inverter fed through a regulated SEPIC converter

In power electronics, it is necessary to select the best converter circuit topology that has good performance among different converters. The single-ended primary inductor converter (SEPIC) has good performance and is advantageous among different direct current/direct current (DC/DC) converters. In this paper, a design of a SEPIC converter is made by selecting the values of its components according to the required output voltage and power. The design is made by an assumption that both of its inductors have the same value. The converter is tested by using MATLAB Simulink successfully. Later, its output voltage is regulated by using a proportional integral (PI-controller) through tuning its proportional and integral gains. Finally, the SEPIC converter is connected to a single-phase full-bridge inverter to supply its required DC voltage. The role of the SEPIC converter is to regulate the dc-link voltage between its output side and the inverter. The results showed the success of this connection to supply alternating current (AC) loads with low total harmonic distortion (THD).

Analysis and design of four-plate capacitive wireless power transfer system for undersea applications

This paper presents a four-plate undersea capacitive wireless power transfer (CPT) system for underwater applications such as autonomous underwater vehicles (AUVs). Generally, a CPT system transfers the power based on electric fields. The complex resonant compensation networks are used to make the CPT system work in the resonant condition. The resonant voltage is always very high. It will be a big challenge to the human safety. In this paper, a virtual electrons periodic reciprocating flow theory is proposed for the CPT system. In one switching cycle, the electrons firstly flow in the forward direction through the forward path and then flow in the inverse direction through the inverse path. The CPT system has been deeply studied with the vacuum dielectric or the air dielectric. However, for the CPT system, there are few papers to show the underwater application. In this paper, an undersea four-plate CPT system is designed and studied in the underwater condition. The two coupling capacitors and other elements of the CPT system could build a closed-loop path. A small value inductor is adapted as a resonant compensation network for the four-plate CPT system. The DC voltage is inverted to the AC voltage in the primary side with the single-phase full-bridge inverter. The resonant voltage is rectified to the DC voltage in the secondary side with the single-phase full-bridge diode rectifier. A 100 W power level CPT system is constructed to verify the theory analysis and the calculation. The theory analysis is verified by the simulated and experimental results. The stable output voltage and load power are achieved in this paper.

Boost Voltage Single Phase Full Bridge Inverter with No Voltage Drop Based on Switched Capacitor

In this paper, a voltage-boost-type non-voltage drop single-phase full-bridge inverter connected to a switched-capacitor structure is proposed. The output voltage of the inverter is controlled by the pulse width modulation of a DSP to control the lead and break of the active switches. The full-bridge switches work at low frequency; the other switches work at high frequency. The inverter uses two capacitor modules to charge and discharge alternately so as to overcome the problem of voltage drop on the output side of the inverter in the transition stage from series capacitor discharge to parallel charge. By analyzing the charge–discharge characteristics of the RC charge–discharge circuit, the capacitor charge–discharge cycle can be adjusted to alter the output voltage within a certain range. The results from the physical construction verify the Simulation results achieved well, which demonstrates satisfactory performance that supports the verification of the above theory.