Inverter Efficiency Research Articles

A Dual Source 13 Level Inverter with Reduced Component Count for Renewable Energy Applications

An innovative multilevel inverter (MLI) relying on switched capacitor (SC) architecture is suggested for single-phase inverters with 13-levels. This suggested SCMLI is expected to be capable of generating output AC voltages at appropriate levels while utilizing fewer switches. The suggested inverter utilizes two count of capacitors, two asymmetrical dc sources, two diodes, and 11 switches. As fewer switches are needed, fewer gate drivers are also needed, increasing the converter's power density. The challenge of preserving self-voltage balance across the capacitors in an SC-MLI circuit is yet another task. Additionally, when the modulation index is low, self-voltage preservation is subpar. It is possible to maintain the self-voltage balance with the capacitors connected in this suggested SC-MLI avoiding the requirement of any ancillary devices or challenging control schemes. Regardless of the modulation index values, capacitors operate at self-balanced levels in all regions of the spectrum. The suggested SC-MLI has a strong ability to achieve good power quality and can balance capacitor voltages even at low modulation indices. The suggested SC-MLI is first modelled using different loading conditions in the MATLAB/Simulink® platform, and subsequently it is validated with the help of typhoon-HIL real-time emulator. Using the simulation tool PLEXIM-PLECS, the suggested inverter's overall switching losses and efficiency are estimated and found out to be 95.87%.

EFFECT OF SHADING ON HALF-CUT SOLAR PANELS POWER OUTPUT

The output power generated by the photovoltaic module and its lifetime depend on many aspects. Some of these factors include: type of PV material, intensity of received solar radiation, cell temperature, parasitic resistance, clouds and other shadowing effects, inverter efficiency, dust, module orientation, weather conditions, geographical location and cable thickness and others. There are several environmental parameters that can affect the performance of solar cells, including changes in temperature, intensity of solar radiation, partial covering of the surface of the solar cell. Partial covering of the solar cell surface is usually caused by dust adhering to the solar panel for a certain period of time or it can also be caused by animal droppings such as birds that accidentally hit and cover the surface of the solar panel. Because it causes the closing of the solar cell, the performance of the solar cell will not be maximized, so it can greatly affect the decrease in the value of the output power and also the current generated. But how big the resulting influence is not yet known. The data logger managed to record the necessary parameters of the PV circuit that is applied to the shadow, namely, Voc voltage, working voltage, working current and power. The application of a rectangular shadow pattern has differences from a circle pattern, namely: in a rectangular pattern: a significant voltage drop occurs when the shadow is applied by 60%, the PV can still emit current although it is relatively small, the PV no longer emits voltage when the shadow is more than 70% , whereas in the circle pattern: the PV voltage starts to drop after the shadow is applied by 30%, if the shadow is more than 30% then the PV is no longer flowing current.

Comparative Study on Analysis of Losses and Leakage Current for Transformer-less Inverters for PV Applications: A Review

Abstract: The reduction in the Common Mode Voltage (CMV) and thermal losses in semiconductors play a crucial role in designing of a new transformer-less inverter topologies for solar powered applications. The galvanic isolation and the leakage current problem due to non-availability of transformer can be addressed either by providing additional switches on the dc side or on the ac side, but this results in more number of semiconductor devices being added into the conduction paths which are switched according to the desired output requirements which further results in high conduction and switching losses indirectly effecting the efficiency of the transformer-less inverters. Hence it is important to study the existing topologies in view of the total losses, CMV and leakage current parameters together. In this review paper H5, H6 and HERIC transformer-less inverter configurations in terms of CMV, Leakage current, Conduction and Switching losses as total losses have been analyzed using PSIM2022.2 simulation software package with the availability of the thermal module. The study of total losses with CMV and leakage current will help in noting the drawbacks of the topologies discussed in this paper.

An Efficient Resonant Pole Inverter With One Single Auxiliary Switch of Each Phase for AC Motor Drive

The brief presents an efficient resonant pole inverter for the sake of the efficiency improvement of the inverter. Its design process is elaborated briefly as follows: the same auxiliary units are added in parallel with three bridge arms and auxiliary units on each bridge arm only consist of one auxiliary switch, two auxiliary diodes, two resonant capacitors and two coupled resonant inductors; when the auxiliary units work, the voltage across main switches can decrease to zero periodically before main switches are switched on. Thus, main switches can acquire zero-voltage switching, making for the reduction of switching loss. In particular, the notable advantage of the presented inverter is that only one switch is included in the auxiliary units of each phase, which is beneficial to the simplification of the control strategy and the restriction on the hardware cost. Moreover, the single auxiliary switch of each phase can also acquire zero-current switching. The brief illustrates each working state in a switching period. The relative experimental waveform indicates that switching devices attain soft-switching. Furthermore, the efficiency of the presented inverter achieves 98% at rated output power, increasing by 0.3%, compared with that in the latest literature. Consequently, the presented inverter is more advantageous in efficiency than other similar soft-switching inverters.

Analysis and control of single‐phase transformerless dual‐frequency grid‐connected inverter

SummaryTo simplify the inverter topology and suppress the leakage current more effectively, a novel transformerless dual‐frequency grid‐connected inverter with a common direct current (DC) bus is proposed. The proposed inverter retains the advantages of the traditional dual‐frequency inverter such as high efficiency and absence of resonance. In the novel topology, the power unit adopts the highly efficient reliable inverter concept (HERIC) topology with a unipolar modulation strategy, and the auxiliary unit adopts the H‐bridge topology with a bipolar modulation strategy. It is verified that the circulating current between the two units can be eliminated in the proposed inverter. The sensitivity of the circulating current is discussed by considering the tolerance of the filter inductances. In the leakage current equivalent circuit, the DC bus of the power unit is connected to the grid through a low‐impedance branch in parallel with the parasitic capacitance. Therefore, the leakage current is effectively suppressed. Finally, the experimental results are provided to verify the performance of the inverter.

(Invited) NiO/ β-(Al x Ga1-x )2O3 /Ga2O3 Heterojunction Lateral Rectifiers with Reverse Breakdown Voltage > 7kV

There is significant recent interest in development of Ga2O3 power devices due to their capability for high temperature operation, reduced on-state and switching losses due to lower on-resistance for high voltage devices, and potentially higher frequency switching capability. These are targeted for renewable energy transmission systems, electric vehicle (EV) traction inverter and motor control systems, fast charging stations and more electric aircraft. Since the efficiency of EV powertrain inverters is partially determined by the efficiency of the switching transistors, it is of interest to examine ultra-wide-bandgap semiconductor electronics. The successful development of these power transistors is expected to significantly increase the longevity of a battery charge and the resultant cost of an EV.In this work, NiO/ β-(Al x Ga1-x )2O3 /Ga2O3 heterojunction lateral geometry rectifiers with diameter 50-100 µm exhibited maximum reverse breakdown voltages >7kV, showing the advantage of increasing the bandgap using the β-(Al x Ga1-x )2O3 alloy. This Si-doped alloy layer was grown by Metal Organic Chemical Vapor Deposition with an Al composition of ~20%. On state resistances were in the range 50-2180 Ω.cm2, leading to power figures-of-merit up to 0.72 MW.cm-2. The forward turn-on voltage was in the range 2.3-2.5 V, with maximum on/off ratios >700 when switching from 5V forward to reverse biases up to -100V. Transmission line measurements showed the specific contact resistance was 0.12 Ω.cm2. The breakdown voltage is among the highest reported for any lateral geometry Ga2O3-based device. Figure 1

Implementation of 3000-watt inverter as a source of electrical energy in solar power plants

In industry, an inverter is a tool/component for adjusting the speed of an electric motor. By using an inverter for electric motor purposes, it becomes a variable speed, whereas the speed can be changed or adjusted as needed. The method used in this study is an experimental research method, namely designing and measuring the system under study. Measurements are made for non-electrical quantities, namely the inverter of the solar module which is generated by the intensity of sunlight hitting the surface of the solar cell. Measurements are also made for electrical parameters such as current, voltage, power factor, and power. Based on the data obtained from all the tests that have been carried out, the system output voltage cannot reach the expected 220 Volts. Because changes in load affect the output voltage of the system were occurred, as the load of 60 W/220V is added, the output voltage drops to 740.5 Volts. As the load is reduced by 60W/220 V, the output voltage increases by 786.9 Volts, within the average inverter efficiency of 77%.

A component sizing prediction study for a series hybrid electric vehicle based on artificial neural network

In the present study, the predictive tool based on an artificial neural network is developed by means of the experimental data of two series hybrid electric vehicles. The experiments have been conducted on different driving conditions, including highways, traffic, and combined driving conditions. Then, the artificial neural network is developed to predict an arbitrary series hybrid electric vehicle’s required power. The instantaneous required power is divided into dynamic and steady power to size the combustion engine, electric motor, and high voltage battery of the series hybrid electric vehicle. The effects of different ambient conditions (including ambient temperature and altitude), the inverter and high voltage battery efficiencies, and the coast-down coefficients on the components sizing of the series hybrid electric vehicle are then investigated in different driving conditions. The results revealed that the maximum instantaneous power of the electric motor is associated with rapid acceleration in low-speed conditions, and the suburban driving route determines the combustion engine’s maximum power. Notably, the Worldwide Harmonized Light-duty vehicles Test Cycle is the most comprehensive among the available driving cycles, and most of the components’ sizes are determined by this cycle except the combustion engine’s maximum power. It is also realized that the cycle-wise investigation can be summarized into the Isfahan-Tehran route and Worldwide harmonized Light-duty vehicles Test Cycle calculations.

Maximum Voltage Gain Tracking Algorithm for High-Efficiency of Two-Stage Induction Heating Systems Using Resonant Impedance Estimation

A boost power factor correction (PFC) circuit has replaced the diode rectifier to improve its poor power factor performance, low efficiency, and output power limitation for conventional induction heating (IH) applications. Accordingly, many studies have been conducted, but they considered only the efficiency of the boost PFC rather than the entire IH system, or their control and design were complicated. In this paper, an algorithm tracking the maximum voltage gain of the resonant network is proposed to improve the entire efficiency of the two-stage IH system based on an exact online resonant frequency estimation. It can make the resonant network operate at the maximum voltage gain point which can improve the efficiency of the series-resonant inverter (SRI) included in the IH system with low circulating current, the minimum switching frequency, and zero voltage switching (ZVS) capability. The proposed algorithm also induces the minimum output voltage of the boost PFC, which can reduce its switching losses and total harmonic distortion (THD). The validity of the proposed algorithm is experimentally verified using a 2.4-kW prototype IH system, including the boost PFC and the IH-SRI controlled by a digital signal processor (DSP).

Grid Harmonics Suppression for Three Phase Dual-Frequency Grid-Connected Inverter Based on Feedforward Compensation

Using a low pulse ratio, the electromagnetic interference and switching loss of an inverter can be effectively reduced, particularly in high-power applications. However, due to variations in grid impedance, it is a challenging task to achieve stable operation of an LCL-type grid-connected inverter (GCI) using the active damping method with low pulse ratio. Thus, a novel three-phase dual-frequency GCI is presented to ensure the symmetry of the output power and the stable operation of the system address stability issues. The proposed inverter topology in this article is composed of two inverters in parallel, which are, respectively, a power inverter unit (PIU) and an auxiliary harmonic elimination unit (AHEU). To reduce the switching loss and improve the inverter efficiency, the switching frequency of the PIU is relatively low, injecting current into the grid. Moreover, the feedforward compensation method is used in AHEU. AHEU operates at high switching frequency to generate a current component that is symmetrical with the ripple com-ponent, improving the power quality, without extracting the current harmonic as the current reference. The operating principle of feedforward compensation is explained, and a proper parameter design procedure is presented in this paper. Since L filters are used for the proposed inverter, the system can operate stably where the ratio of switching frequency to fundamental frequency is low. A 10 kW laboratory prototype was built. The experimental results showed that the grid current ripple could be effectively eliminated and the THD of the grid current was 3.01%. The proposed inverter has good stability in a weak grid, and the efficiency of the proposed inverter is 95.98% at rated current, which is 0.81% higher than the traditional GCI, effectively increasing the efficiency of the system.

Analisis Kinerja PLTS 200WP Secara Realtime Menggunakan IoT

Technological developments occur in various ways, for example wireless communication technology, computer networks and the internet, designing monitoring and control systems based on the Internet of Things (IoT). The application of the IoT concept has been widely carried out with various studies in various fields of life including analyzing solar panels in real time which can be done by utilizing the development of micro and wireless and internet-based control technology called IoT. The performance of a PLTS can be assessed by calculating the efficiency of the PLTS components themselves. The purpose of this study is to analyze the performance of a 200Wp PLTS from IoT-based Blynk application data. The methodology used in this study starts from 1) tool design; 2) tool making; 3) tool testing; 4) evaluation. From the results of the study it was found that the efficiency of solar panels was 11.35% The efficiency of SCC was 93%, the efficiency of Baerai was 94.8%, the efficiency of inverters was 92.6%, and the total efficiency of PLTS was 9.29% . The efficiency of this PLTS is considered low for a 200Wp PLTS

Spatially resolved generation profiles for building, land and water-bound PV: a case study of four Dutch energy transition scenarios

Abstract. Alongside a transition from steerable and centralized traditional electricity generation to intermittent and more decentralized renewable electricity generation from solar panels and wind turbines, Dutch energy transition scenarios project a widespread deployment of heat pumps and electric vehicles towards 2050. While clearly contributing to the decarbonization of the Dutch energy system, these developments impose challenges regarding electricity supply-demand mismatch and grid congestion. Spatially resolved electricity demand and supply profiles are required to gain a better insight into where and when such problems are likely to occur within the different scenarios. The present paper focuses on Dutch solar energy supply and features the construction of geodatabases of scenario-specific, spatially resolved electricity generation profiles for building, land and water-bound PV. Country-level PV capacities are geographically distributed based on spatial variance in roof PV potential and availability of suitable land and water use areas. Corresponding electricity generation profiles are constructed using historical meteorological measurements, a diffuse fraction model and a anisotropic transposition model. Empirically found performance ratio profiles are applied to account for a multitude of performance loss factors, including shading, dust and inverter efficiency. In 2050, building-bound capacity is projected to show only limited overlap with both land-bound and water-bound PV capacity. On the other hand, regions with considerable water-bound PV capacity also tend to show considerable land-bound PV capacity. Compared to the present-day situation, yearly country-level PV electricity generation is projected to be a factor 18.5, 15.7, or 7.7 higher in 2050 when respectively following the Regional, National or International Steering scenarios.

Experimental evaluation of a 1 kW proton exchange membrane fuel cell with resistive, DC and AC loads

In this communication, an experimental investigation is carried out on a PEM (Proton Exchange Membrane) fuel cell. A small-scale standalone PEM fuel cell system of 1 kW capacity is demonstrated in the present study. The fuel cell is connected to the charge controller, and the charge controller is further connected to the DC and AC loads to study the fuel cell characteristics. A battery bank backup is also provided to account for the stable power output from the fuel cell. The purpose of the study is to determine the fuel cell's performance when operated with resistive, AC, and DC loads (home appliances within the rated power range). The effect of hydrogen flow rates on the power output is also presented in this paper. The DC and AC loads are connected to the fuel cell setup to study the characteristics of the fuel cell. From the study, it can be observed that the performance of the fuel cell is better at higher flow rates of hydrogen. The experimental results showed that the maximum power obtained was 986.8 W at a hydrogen supply rate of 15 LPM. The maximum fuel cell efficiency was found to be 44% at the flow rate of 8 LPM. The charge controller efficiency reported for DC and AC load connections is 94.97% and 96.98%, respectively. The inverter efficiency was observed to increase with the current value, with the maximum value reaching around 98.86%.

Development and Performance Evaluation of Integrated Hybrid Power Module for Three-Phase Servo Motor Applications.

This study aims to develop a 30 kHz/12 kW silicon carbide (SiC)/Si integrated hybrid power module (iHPM) for variable frequency drive applications, particularly industrial servo motor control, and, additionally, to theoretically and experimentally assess its dynamic characteristics and efficiency during operation. This iHPM integrates a brake circuit, a three-phase Si rectifier, and a three-phase SiC inverter within a single package to achieve a minimal current path. A space-vector pulse width modulation (SVPWM) scheme is used to control the inverter power switches. In order to reduce parasitic inductance and power loss, an inductance cancellation design is implemented in the Si rectifier and SiC inverter. The switching transients and their parasitic effects during a three-phase operation are assessed through an electromagnetic-circuit co-simulation model, by which the power loss and efficiency of the iHPM are estimated. The modeled parasitic inductance of the inverter is validated through inductance measurement, and the effectiveness of the simulated results in terms of switching transients and efficiency is verified using the experimental results of the double pulse test and open-loop inverter operation, respectively. In addition, the power loss and efficiency of the SiC MOSFET inverter are experimentally compared against those of a commercial Si IGBT inverter.

Investigation of efficient multilevel inverter for photovoltaic energy system and electric vehicle applications

Introduction. This research presents a simple single-phase pulse-width modulated 7-level inverter topology for renewable system which allows home-grid applications with electric vehicle charging. Although multilevel inverters have appealing qualities, their vast range of application is limited by the use of more switches in the traditional arrangement. As a result, a novel symmetrical 7-level inverter is proposed, which has the fewest number of unidirectional switches with gate circuits, providing the lowest switching losses, conduction losses, total harmonic distortion and higher efficiency than conventional topology. The novelty of the proposed work consists of a novel modular inverter structure for photovoltaic energy system and electric vehicle applications with fewer numbers of switches and compact in size. Purpose. The proposed system aims to reduce switch count, overall harmonic distortions, and power loss. There are no passive filters required, and the constituted optimizes power quality by producing distortion-free sinusoidal output voltage as the level count increases while reducing power losses. Methods. The proposed topology is implemented with MATLAB/Simulink, using gating pulses and various pulse-width modulation methodologies. Moreover, the proposed model also has been validated and compared to the hardware system. Results. Total harmonic distortion, number of power switches, output voltage, current, power losses and number of DC sources are investigated with conventional topology. Practical value. The proposed topology has proven to be extremely beneficial for implementing photovoltaic-based stand-alone multilevel inverter and electric vehicle charging applications.

Analysis of Photovoltaic System in Unbalanced Distribution Systems Considering Ambient Temperature and Inverter Efficiency

Analysis of Photovoltaic System in Unbalanced Distribution Systems Considering Ambient Temperature and Inverter Efficiency

An Efficient Resonant Pole Inverter Without Constant Circulating Current Loss in the Auxiliary Circuit

An Efficient Resonant Pole Inverter Without Constant Circulating Current Loss in the Auxiliary Circuit

Design and Implementation of Closed loop control for Flyback Converter

One of the high frequency switching power supply circuits is the flyback converter. Due to its inexpensive cost and electrical isolation properties, it is mostly employed in low power applications. It is well known that high frequency switching results in losses and lowers inverter efficiency, particularly at low powers. Consequently, a flyback DC-DC converter that is run in a closed control loop is explained in this study. Closed-loop control is the proposed topology for the flyback converter. For the same input/output conditions, the findings from the closed-loop converter are compared to those from the open-loop feedback topology. A closed-loop flyback has been found to be more effective than an open-loop flyback. MATLAB simulates the outcomes. One of the high frequency devices is the flyback converter.

A New Nine-Level Highly Efficient Boost Inverter for Transformerless Grid-Connected PV Application

Transformerless grid-connected multi-level <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PV</i> (photovoltaic) inverter has the major concern of leakage current and buck behavior of output voltage, hence not suitable for low voltage PV applications. A new <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">9L4x</i> (nine-level quad boost) highly efficient inverter based on the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SC</i> (switched capacitor) with a <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">CG</i> (common ground) configuration has been proposed in this paper, which provides four times the gain of input voltage. Hence, this inverter is preferable for low voltage <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PV</i> applications without any boost dc/dc converter intermediate stage. The inverter is designed in such a way that total conducting switches for different level generation is minimum. This technique helps to increase the efficiency of the inverter. Two <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">SC</i> cells are utilized to step-up the input <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PV</i> voltage and facilitate nine steps in output voltage. The common grounding feature of the proposed inverter topology helps mitigate the leakage current. Additionally, this new inverter can handle reactive power during the grid’s lagging/leading pf (power factor) condition. To regulate the active and reactive grid power, a <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PR</i> (proportional resonant) controller is designed. The proposed modulation strategy balances the voltages of switched capacitors at their base voltage with allowable ripple. The inverter circuit details, control strategy, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">PWM</i> (pulse width modulation) scheme, thermal modeling, and loss analysis with component design guidelines are described in detail. Experimental results are presented to validate the effectiveness and feasibility of this proposed inverter.

Analisis Pengaruh Angin dan Suhu Lingkungan Terhadap Kinerja Sistem PV Surya Atap: Studi Kasus 52,2 kWp Pusat Penelitian dan Pengembangan PT PLN Sistem PV Atap

This study aimed to observe the influence of weather parameters (irradiation, ambient temperature, PV module temperature, wind speed, and direction). Performance evaluation of rooftop PV systems is carried out according to IEC 61724-1:2017. The parameters measured are solar irradiance using a pyranometer, the surface temperature of the PV module using a temperature sensor, ambient temperature, wind speed, and direction using the Smart Weather Sensor Lufft type WS500-UMB. The analysis was performed under three different weather conditions: cloudy, rainy, and sunny skies. In rainy conditions, the highest efficiency of the PV array is 16.1% – 16.69%, because the environmental temperature and the temperature of the PV module when it rains is the lowest compared to sunny and cloudy conditions. In sunny skies, the highest inverter efficiency is obtained, around 97.9 – 98.84%, this is due to very high solar irradiation (more than 1000 W/m²), so the inverter works more optimally than in rainy and cloudy conditions. The highest average wind speed is obtained in sunny conditions, which is 3.28 m/s with the same wind direction, namely the West-Northwest, but the influence of the wind is not significant to provide a cooling effect to the rooftop PV.