Output Power Gain Research Articles

Active reallocation of photogenerated carriers by triboelectric electro-field for improving nonuniformly illuminated photovoltaic module

Different from standard indoor testing for photovoltaic (PV) cells, the outdoor working of large PV modules suffers an inevitable issue of nonuniform illumination. Even a 10 % partial area shading results in an 80 % power attenuation. This can be attributed to the endogenous lateral transfer of photogenerated carriers between differently illuminated zones. Herein, we presented an active reallocation strategy for rationalizing lateral carrier transfer inside PV modules, which utilizes triboelectric electro-field to dynamically balance the p-n junction barrier height at interfaces of different illumination states. As demonstrated by a flexible hybrid energy harvester combining triboelectric nanogenerators (TENGs) and solar cells, by managing with rectifier-free circuits or even small chips, a small power sacrifice of TENGs exchanges for remarkable performance improvement of PV modules, leading to a power output gain of up to 87.7 % for half-shaded PV modules of different material and structural configurations. Besides, the reallocation electric field adapts well to a wide range of voltage or even pulsed triboelectric voltage, providing a mutually beneficial energy management technology for multi-source energy harvesting. This strategy of active reallocation by triboelectric effect provides an endogenous PV module promotion approach with prominent structural adaptability for distributed or even portable on-body power generation.

A novel modified switched capacitor multilevel inverter using SARC-DQRLC controlling mechanisms for grid systems

Currently, the solar photovoltaic (PV) systems are becoming more and more important in order to meet the world's increasing demand for electricity. In this study, a unique Hybrid Group Search Integrated Rider (HGSR)-MPPT control technique is developed to track the maximum solar energy from the PV panels in order to meet the grid systems' need for electricity. Then, the output voltage of the PV is boosted using the cutting-edge Cuk Step-Up converter, which has a higher voltage gain efficiency and lower stress voltage between the switches. Consequently, the Self-Adaptive Rao Control (SARC) technique is implemented to produce the pulses required to actuate the converter's switching components. More specifically, the improved switched capacitor five-level inverter circuit is modelled in this study to improve the grid unit's power quality with low leakage current, switching stress, and minimal component consumption. In order to improve the performance of the MLI's switching operating modes, the unique Deep Reinforced Q-Learning Control (DRQLC) technique is implemented. The output voltage, current, power, THD, and voltage gain efficiency of the proposed controlling mechanisms' simulation results are evaluated and analyzed.

Innovative design for thermoelectric power generation: Two-stage thermoelectric generator with variable twist ratio twisted tapes optimizing maximum output

In recent years, considerable effort has been dedicated to the development of highly efficient thermoelectric generators for waste heat recovery and thermoelectric power generation. In this study, we present employing twisted tapes with variable twist ratio to enhance thermal energy extraction efficiency, coupled with two-stage thermoelectric modules for heat-to-electricity conversion, resulting in a substantial increase in the power output of the thermoelectric generator. We established an experimental system that validated the superior power generation and heat recovery characteristics of the two-stage thermoelectric generator. Building upon these findings, we propose further optimizing the variable twist ratio twisted tapes to enhance the power output. We investigated the impact of tape pitch ratio, twist ratio, and twist ratio variation range on thermoelectric performance. Experimental results indicate that the influence of flow instability is more pronounced than that of swirl intensity, and twist tapes with the maximum twist ratio variation rate yield the highest net output power. Compared to an unmodified thermoelectric generator, the two-stage thermoelectric generator employing twist tapes with a twist ratio increase from π to 3π achieves a maximum net output power gain of up to 100%. These findings provide a practical framework for integrating innovative power generation modules and optimized heat exchanger designs into the application of waste heat recovery thermoelectric generators, marking a significant advancement in the field of thermoelectric generators.

Research on Power Balance Control Method of Electronic Transformer

Aiming at the problem of poor output stability and power gain of the power electronic transformer of the microgrid energy storage system, a power balance control method for the power electronic transformer of the microgrid energy storage system based on parallel modular multi-level commutation control is proposed. The reactive power outer loop parameter fusion method is used to sample the power dynamic load parameters and information fusion processing for the transformers in the system. According to the static limit active power adjustment of the fuzzy parameter factors on the output voltage side of the DC port, the steady-state gain of the power electronic transformer of the microgrid energy storage system is calculated. The static current limiting adjustment method is used to construct the feedback compensation model of the power electronic transformer of the microgrid energy storage system. In the active power control loop, the optimal design of the power electronic transformer power balance control of the microgrid energy storage system is realized through transient stable power adjustment. The test results show that using this method to perform power balance control on the power electronic transformer of the microgrid energy storage system has high output stability and good active power balance, which improves the robustness and adaptability of the transformer balance control.

Source Network Load Storage Access to Power Wireless Private Network Technology Based on 5G Ultra Dense Networking

We make the source network load storage access power wireless private network, this paper proposes a source network load storage access power wireless private network technology based on 5G ultra dense network. The multiple rotation scheduling and self-organizing learning methods are used to establish the deployment model of the source network load storage access node of the power wireless private network under the 5G communication mode. According to the routing control algorithm design of the 5G ultra dense networking node, combined with the integration analysis of the access load parameters, the source network load storage access model of the 5G ultra dense networking under the dynamic load distributed control mode is established. Through the method of optimal control of reactive power and voltage of distribution network, the transmission link equilibrium structure model of 5G source network load storage access to power wireless private network is constructed. Combined with the coverage analysis of link topology structure and the benefit maximization constraint analysis of production and consumption users, the active and reactive capacity analysis of transaction between production and consumption user groups and multiple production and consumption users is adopted. Combined with the energy storage characteristics analysis and power flow parameter calculation of the source network load storage access power, the 5G ultra dense networking and private network access to the source network load storage access power are realized. The test shows that this method has better power balance dispatching ability and larger output power gain when it is applied to the design of source network load storage access power wireless private network.

A new design approach for dual-band power amplifiers based on dual-band HCC and bandpass filter

This paper introduces a novel design approach based on the dual-band harmonic control circuit and bandpass filter for dual-band power amplifiers. The circuit schematic of the proposed approach is constructed using four resonators and RFC inductors. The first two resonators are dedicated to controlling the second harmonics, while the third and fourth resonators serve as a harmonic blocker, allowing only the main signals to pass through to the load. Subsequently, all components are replaced by circuits based on microstrip elements, forming the proposed OMN. This OMN includes a novel wideband bias circuit, elliptically coupled resonators, and a new dual-band bandpass filter. To ensure compatibility with the transistor, a compensator line has been integrated. As a result, a dual-band power amplifier has been fabricated and measured at two operating frequencies, 2.1 GHz and 2.91 GHz. The measured values for drain efficiency, output power, and power gain at 2.1 GHz are 75.98%, 37.5 dBm, and 12.5 dB, respectively. Similarly, at 2.91 GHz, these values are 75.73%, 37.24 dBm, and 12.24 dB, respectively.

A Low-Power V-Band Radar Transceiver Front-End Chip Using 1.5 V Supply in 130-nm SiGe BiCMOS

Energy-efficient, low-voltage, and low-power millimeter-wave (mm-wave) radars are gaining increasing attention for battery-powered commercial applications. In this article, the design of a low-power <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">V</i> -band radar sensor based on a transceiver (TRX) front-end chip using 1.5 V supply in an advanced SiGe BiCMOS technology with 300 GHz <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{f}\textsubscript{T}$</tex-math> </inline-formula> and 500 GHz <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\textit{f}\textsubscript{max}$</tex-math> </inline-formula> is presented. The monostatic front-end chip utilizes low-voltage low-power circuit-level design techniques to achieve measured 9-dBm transmitter (TX) output power and 27-dB receiver (RX) gain with a simulated 3.8-dB noise figure (NF) consuming a total of only 72 mW in continuous mode. The TRX chip is used to build a radar sensor, which is experimentally verified in an anechoic chamber. The low-power sensor achieves a 46-dB dynamic range and a ranging precision better than 3.4 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> m measured with a static target at 1 m. Phase measurements using the low-power radar in the continuous-wave (CW) mode demonstrate that submillimeter movements can be tracked, and notably main vital parameters of a human can be determined accurately. Experimental results show that the performance of the proposed low-power TRX front-end chip is very competitive with designs in modern CMOS technologies.

Energy, exergy, economical and environmental analysis of photovoltaic solar panel for fixed, single and dual axis tracking systems: An experimental and theoretical study

This investigation focuses on energetic, exegetic, economical and environmental analysis of PV solar system using fixed, single- and dual-axes tracking systems under climatic weather of Zakho city/north of Iraq. Experiments are carried out on 5th September 2022. The energy and exergy analyses are used to predict the performance of three solar panels. The theoretical work includes technical, economical and environmental analysis of proposed 1 MW PV solar power plant are presented using similar characteristics of the experimental data of hourly meteorological climatic conditions during 2022. The findings display that the tracking systems have significant influences on 4–E performances. The experimental results displayed that electrical output power gain and thermal exergy output are increased when using tracking systems, where the exergy losses for single- and dual-axes tracking systems are decreased as compared to fixed solar plane. The maximum improvements in the electrical output power gain of PV solar panels using dual– and single–axes tracking systems are nearly reached to 40 % at 8 a.m., 13 % (for single) and 20 %(for dual) at 12 p.m. and 30 % at 17PM as compared to fixed solar panel. The theoretical results display that the yielded produced energy for single- and dual-axes are increased by 16.5 % and 25.5 %, respectively, as compared to fixed panel. The economic findings display that the cost of energy for single-axes, dual-axes and fixed tracking systems are 4.89, 4.41 and 8.26, respectively. Finally, the use of tracking systems reduces the CO2 emission about 4000–4500 tCO2 annually.

Thermal and electrical performance analysis of monofacial double-glass photovoltaic module with radiative cooling coating on the rear surface

The monofacial double-glass photovoltaic modules are still seriously affected by the temperature effect. The coatings with spectral regulation characteristics are expected to reduce the impact from the temperature effect. A coupled thermal-electrical model was established to evaluate the thermal and electrical performance of the monofacial double-glass modules applied with different spectral regulation coatings, including sub-bandgap reflection coating, mid-infrared emission coating and a combination of the two coatings. The cooling effect and output power gain of these coatings on the front and rear surface of the modules were compared comprehensively. The results show that the most suitable cooling coating for the module is the mid-infrared emission coating (i.e. radiative coating) on the rear surface when absorption loss of solar cell caused by spectral regulation coating was considered. Thus, we prepared the radiative coatings of TPX/SiO2 by doping SiO2 particles into the TPX polymer matrix. The thermal and electrical performances of the modules applied with different coatings on the rear surfaces of PV modules were calculated to optimize the coating parameters, such as thickness, size and volume fractions of SiO2 particles. The results reveal that the module applied with the TPX/SiO2 coating (size: 50 nm, volume fraction: 5 vol%, thickness: 60 μm) on the rear surface exhibited the lowest temperature and the highest output power. In the outdoor experiments, the radiative coating realized the cooling effect of ∼1 °C, and the efficiency improvement of 0.21 %. This work demonstrates that radiative cooling coating on the rear surface can bring PV module heat dissipation. Further research and development of radiative coatings would improve the cooling and electrical performances of PV module.

Design of dual-band power amplifier using bandstop filter and dual-mode bias circuit for multistandard transceiver systems

This paper presents a dual-band power amplifier (PA) using a meandered line bandstop filter (BSF). An important challenge addressed in this design is to achieve proper isolation between the operational bands of the amplifier. The proposed BSF provides isolation and efficiency, effectively separating the output power and power gain between the two operational bands. Additionally, a dual-mode bias circuit is designed to serve as an inductor choke and control the second harmonics for both operating frequencies simultaneously. Two dual-band PAs, utilizing LDMOS and GaN HEMT transistors, have been designed using the proposed output matching circuit, which incorporates the BSF, bias circuit, and compensation circuit. The results obtained from both PAs, employing different transistors, are identical. Based on the presented concepts, a dual-band PA with an LDMOS transistor has been fabricated and measured. The measurements reveal an efficiency of 79.23%, an output power of 39.85 dBm, and a power gain of 14.85 dB at a frequency of 0.7 GHz. Similarly, at a frequency of 1.9 GHz, the efficiency is 77.24%, the output power is 38.22 dBm, and the power gain is 13.22 dB.

Reversed Cherenkov radiation amplifier with compact structure and high efficiency

Based on the reversed Cherenkov radiation excited in metamaterials, a novel S-band reversed Cherenkov radiation amplifier (RCRA) with two output ports is proposed in this paper. Its metamaterial slow-wave structure (MSWS) consists of a hollow circular waveguide periodically loaded with all-metal double-ridge complementary electric split-ring resonators (CeSRRs). The CeSRR exhibits subwavelength and strong resonance characteristics, which lead to miniaturization and high interaction impedance of the MSWS. The period of the MSWS is optimized using the phase velocity jump technique to further increase the output power and electronic efficiency. The simulation results demonstrate that when the microwave signal of 7.8 W at 2.286 GHz is inputted at port 2, the output power at port 1 is 307 W, and the saturated output power and saturated gain at port 3 are 5.48 kW and 28.47 dB, respectively. Notably, the total electronic efficiency of the RCRA is predicted as 33.84%. The RCRA features high electronic efficiency and miniaturization and may meet special application scenarios that require two output microwave signals at the same frequency.

Graphical Approach to Optimization of Maximally Efficient-Gain-Boosted Feedback Amplifiers

It is challenging to design high-gain amplifiers near the maximum oscillation frequency (fmax) of the transistors. This paper presents a comprehensive graphical approach to maximize the gain of feedback amplifiers with maximally efficient gain (GME) conception at near-fmax frequency. The complex gain-plane and the reflection-coefficient-plane are utilized to provide clear insights into both the gain and stability states of the two-port device while boosting GME. An efficient flowchart to synthesize feedback amplifiers is given, which optimizes the GME of a two-port device while ensuring the stability. A 210 GHz power amplifier in 40 nm CMOS was designed and optimized based on the proposed approach. The feedback circuit of the transistor pushes it to become potentially unstable and boosts GME. The measured peak small-signal gain was 10.48 dB at 195.33 GHz. The measured saturation output power and large-signal gain at 210 GHz were 3.04 dBm and 7.08 dB, respectively. The presented method could facilitate terahertz amplifier design.

Analytical Approach to Improve the Performance of a Fully Integrated Class-F Power Amplifier with 0.13 µm BiCMOS Technology Using Drain–Bulk Capacitor Modulation

This article reports a novel technique based on drain–bulk capacitor modulation to improve the performance design of a class-F power amplifier (PA) used in low-power transceivers based on the I-Q amplitude modulation technique considering linearity–efficiency–miniaturization trade-offs. This idea is carried out by implementing a tuned capacitor in parallel with a cascode transistor on the output of the power stage to enhance the shape of the voltage–current amplitudes of the class-F PA by creating a new harmonic current component. Simulated results were obtained for the power back-off region of the proposed configuration, with an output power, power gain and power-added efficiency of 8 dBm (+ 5 dBm)B, 19 dB (+ 5 dB)B and 45% (+ 5% to 10%)B, respectively. In addition, post-layout simulations revealed a similar level of output power, a power gain of a 20 dB and a 28% power-added efficiency for an added capacitance equal to 1.3 pF. Class-F PA is implemented on a 732×605 μm2 chip’s surface. (B: indicates the improved values in the power back-off region).

Comparative study of two combined blowing and suction flow control methods on pitching airfoils

A comparative study of two combined blowing/suction flow control methods was conducted on the pitching airfoil using the unsteady Reynolds-averaged Navier–Stokes (URANS) method. One used leading-edge blowing and trailing-edge suction, which is referred to as a co-flow jet (CFJ), and a conformal slot CFJ (C-CFJ) was adopted. Another used leading-edge suction combined with trailing-edge blowing, which was called reversed CFJ (R-CFJ). The S809 airfoil was used as the baseline as its stall characteristic is suitable for separation flow or stall control research. Aerodynamic coefficients of these two combined blowing/suction methods were compared under no-stall, mild-stall, and deep-stall cases. The net gain of output power was also discussed if CFJ methods were used for wind energy applications. The influence mechanism of these two methods on the flow around the airfoil was revealed. The results showed that the C-CFJ is suitable for the no-stall and mild-stall cases, while the R-CFJ is suitable for the deep-stall case. Leading-edge suction is more stable than leading-edge blowing when suppressing the dynamic stall. The leading-edge jet flow will cause dynamic stalls when it is detached from the airfoil surface, while the detached jet flow can block the development of the separation when it is placed on the trailing edge.

Hybrid wind–solar energy and resource simultaneity: An Indian case study for site selection and feasibility check

The integration of wind–solar energy into hybrid system improves synchronization and lowers power generation variations. It is crucial to consider resource simultaneity when selecting a hybridization location. The current study uses data from 41 years of hourly ERA5 reanalysis to analyze the coexistence of wind and solar energy sources (1979–2019). To take into account the combined impact of simultaneity and capacity factor (CF), as well as to show the viability of establishing a new hybrid power plant for base-load and peak-load applications, a novel hybrid power exploitability index (HPEI) is developed. Additionally, by analyzing the yearly power output gain that may be attained through hybridization, the viability of retrofitting existing freestanding power plants has been examined. According to the findings, resource complementarity abounds in India’s southern region and along its western coast, whereas resource synergy prevails in the northern region. Furthermore, the largest peak CF for wind and sun, respectively, are predicted to be in the southern coastline (51.56%) and northern Himalayan areas (28.48%). In seven of the eight research locations, it has been shown that it is possible to hybridize independent power plants that already exist, with the addition of equal capacity potentially increasing yearly power output by up to 400%. In order to achieve net-zero emissions, hybridizing RE can meet the need for clean energy. Project developers will use the findings of this research to determine where to construct new power plants and where to hybridize existing ones.

A Floating-Body Transistor-Based Power Amplifier for Sub-6-GHz 5G Applications in SOI CMOS 130-nm Process

A floating-body transistor based two stages power amplifier (PA) with lateral NPN based bandgap voltage reference (BVR) is implemented in a 130 nm Silicon-On-Insulator (SOI) CMOS process for sub-6GHz 5G applications. Floating-body (FB) transistors instead of traditional body-contacted (BC) transistors have been adopted in driver stage and power stage amplifiers of the proposed PA. On-chip input and output transformer baluns (TB) are customized designed for this PA which can realize impedance matching. Split push-pull structure is adopted in both driver stage and power stage with inter-stage matching networks. Incorporating bonding wire multi-physics models into input and output matching and power gain temperature compensation, the proposed PA can achieve maximum 25.6 dB power gain, 22.2 dBm output power and 28% power added efficiency (PAE) at 1 dB compression point (OP-1dB). The 3 dB bandwidth of the proposed PA is from 4.3 GHz to 6.4 GHz and the core size is 0.59 mm2. When the proposed PA is used for IEEE 802.11ac application and measured at VHT80 MCS9 (80MHz, 256-QAM), it can achieve 21.4 dBm output power and 24.8% PAE at 5.5 GHz operating frequency with −36 dB error vector magnitude (EVM).

Design of a dual-band microwave power amplifier for wireless communications

In this paper, we present a design of a concurrent dual-band power amplifier operating at 5.8 GHz and 9.4 GHz employing a MMIC technology for wireless communications. The active device used is a 0.25 µm AlGaN/GaN HEMT from WIN Semiconductor, Taiwan. The design goal is to achieve the high-efficiency while still retaining other important metrics including output power and power Gain at concurrent dual frequency bands. The performance of the designed amplifier is evaluated at both small and large signal levels through theoretical analyses and simulation using a Keysight ADS simulator. The developed dual-band amplifier delivered a 47% PAE with 30.5 dBm output power and 12.5 Gain at 5.8 GHz, and a 37% PAE with 30.2 dBm output power and 12.2 Gain at 9.4 GHz.

Losses in bifacial PERC solar cell due to rear grid design and scope of improvement

Photovoltaic (PV) industries are continuously trying to improve the module performance with the adoption of newer cell technologies. Recently, bifacial passivated emitter rear contact (PERC) solar cell technology has entered the market to further improve the module performance through the absorption of the extra photons reflected from the background. This work is mainly focused on optimizing the rear side grid pattern of the bifacial PERC solar cells for improvement of the total output power gain. We have developed an analytical model based on the front and rear grid pattern of commercially available bifacial PERC solar cells to calculate the optical shading and electrical losses for both sides of the solar cells. It is perceived that the rear shading loss due to rear grid design of industrial bifacial PERC solar cells is very high (∼30%) as compared to the front side (∼5%) of the cells. The model calculation shows that if with the improved laser scribing technology the finger width of the rear grid pattern be drastically reduced from ∼ 200 μm (measured value) to 25 μm the optical shading loss may be minimized to 11–14% from 30% without compromising the effective busbar resistance.

Large Eddy Simulation of wind turbine fatigue loading and yaw dynamics induced by wake turbulence

A coupled Large Eddy Simulation (LES) and aeroelastic code was used to evaluate control responses and fatigue loading of a four-inline wind turbine array. Neutral and unstably stratified atmospheric boundary layers with hub-height wind speeds of 7 and 15 m/s were used for wind farm inflows. These cases operate in different control regions. It was found that for both incoming wind speeds, atmospheric stability has no significant impact on the fatigue loads of the front-row wind turbines. However, stability affected wake characteristics which caused differences in control response and fatigue experienced by downstream turbines. The most distinctive difference was observed at a downstream turbine in the above-rated condition where the shaft torsional load in neutral stability condition was up to 50% higher than the unstable case. A baseline active yaw controller was implemented in the below-rated condition, which caused higher fatigue on turbines in the wake compared to the fixed yaw turbine case, without any power output gain.

Light-induced performance of SHJ solar modules under 2000 h illumination

The light-induced degradation (LID) of solar module leads to severe loss in generated power due to the formation of recombination active defects. The silicon heterojunction (SHJ) solar cells based on n-type wafers are less affected by the LID test. In this paper, the glass/back sheet structure (GBS) modules with different encapsulant materials (TPO, POE, EVA) were laminated to evaluate their performance changes under 2000 h light soaking stress for the first time. The current-voltage (light I–V, dark I–V) parameters of the modules were measured, as well as the external quantum efficiency (EQE) and electroluminescence (EL), to verify the effect of light irradiation on SHJ solar modules. The SHJ modules with different encapsulant materials show excellent light-induced reliability. There is no degradation after 2000 h light irradiation, and even exhibits light-induced performance increase. The gain in output power (Pmax) is up to 1.41%, which is primarily due to an improved open-circuit Voltage (Voc) and fill factor (FF) as the result of a reduced density of recombination-active interface states. The front sheet/back sheet (FBS) modules also verified the accumulated light-induced stress could result in deteriorating interconnection between SHJ solar cell and ribbon, which suffers from significant output power degradation. The LID-free SHJ solar cells show great potential for lower levelized cost of energy (LCOE) of photovoltaic power generation.