Power Loss Analysis Research Articles

A transformerless common ground‐based 1‐ϕ single‐stage switched boost inverter for solar photovoltaic applications

AbstractThis paper proposes a transformerless common ground based single phase single‐stage switched boost inverter for solar photovoltaic (PV) applications. In the proposed inverter, the input DC source and output AC load share a common ground. As a result, the high‐frequency common mode voltage across the parasitic capacitance is eliminated, resulting in negligible leakage current ( ) and the associated power loss, and harmonics in the inverter. Moreover, the higher voltage gain of the inverter facilitates the inverter to operate with high modulation index and lower shoot through (ST) duty ratio. Hence, the DC link voltage requirement across the inverter leg is reduced. Consequently, the voltage stress across the switches is minimized. Here, a modified PWM control technique is adopted, where the dual active states of the proposed inverter reduce the inductor current ripple and make it suitable for solar PV applications. The voltage boosting capability of the proposed inverter is extendable with the help of an additional number of intermediate impedance sub‐networks. The detailed steady‐state analysis of the proposed inverter is verified with the help of MATLAB simulation. To verify the simulation results, a 200 W, 120 V, and 50 Hz experimental prototype is developed. The prototype is tested for unity and lagging power factor load conditions with a wide range of input DC voltages, and all the major results are included in the paper. The power and thermal loss analysis is carried out using PLECS software, and the results show that the inverter has a maximum efficiency of 97.48%. From the experimental results, it can be inferred that the proposed inverter has a higher modulation index, lesser inductor current ripple, and zero leakage current as compared to the contemporary inverters.

Fulfillment of Some Important Voltage Harmonic Standards in a FPGA Controlled CHB Multilevel Inverter Utilizing Improved SHM-PAM Technique

In the area of medium voltage and high power multilevel inverter applications, good quality power output can be achieved by minimizing lower-order harmonic components, and the SHM-PAM scheme produces best results in this context. The minimization of selective lower-order harmonics rather than their complete elimination makes it more useful to comply certain grid code standard. This article proposes an improved SHM-PAM scheme for a 3-phase 7-level CHB-MLI utilizing three new half-wave (HW) symmetry waveforms to comply with six well-known grid code standards, namely CIGRE WG 36-05, EN 50160, NRS 048-2, IEC 61000-2-12, IEC 61000-3-6, and ER G5/4. The optimal switching transients and necessary dc-link voltages have been determined for controlling the CHB MLI using the recently reported dragonfly algorithm (DA). The efficacy of the reported scheme is evaluated satisfactorily by simulation study and hardware investigation on a CHB-MLI laboratory prototype. The power loss analysis of the CHB inverter for the proposed schemes is evaluated for the entire power factor range. Additionally, to demonstrate the suggested method's superiority in terms of necessary commutation angles for grid code fulfilment, a comparative study has been carried out with a number of pre-existing modulation-schemes.

Analysis of Power Losses in Constrained Cycloid Drive

Analysis of Power Losses in Constrained Cycloid Drive

Studi Rekonfigurasi Jaringan Distribusi 20 kV pada Penyulang DPRD ULP Cianjur Kota Menggunakan ETAP

In the distribution of electricity from electric power sources to consumers who are located far apart, they always experience losses, namely in the form of voltage drops and power losses. However, the voltage loss that occurs in the process of distributing electrical energy is a waste of energy if it is not controlled optimally. Concerning the quality of service, the main factor which becomes the benchmark is the continuity of service and the quality of service voltage. The impact of these losses results in low levels of service quality to customers. Analysis of voltage drop and power loss is needed to determine the size of the voltage drop at the end of the DPRD feeder network. The calculation of voltage drops and power loss uses simulation results of ETAP method. The results of mathematical calculations and simulations are analyzed to determine the factors that cause the voltage quality at the end of the DPRD feeder network to be below the standard service voltage of 20 kV. The results of the analysis and simulation show that the factors that cause the voltage quality at the end of the DPRD feeder to be below the standard of service quality level are the transformer loading system, the type of conductor, and the distance of the substation to the far end of the feeder network. Then the problem was resolved by changing the type of conductor and reconfiguring it by shifting part of the load to the Lampegan feeder so that the voltage profile at the end of the DPRD Feeder was initially 17.527 kV after reconfiguration increased to 18.137 kV.

Optimizing Distributed Generation Placement and Sizing in Distribution Systems: A Multi-Objective Analysis of Power Losses, Reliability, and Operational Constraints

The integration of distributed generation (DG) into distribution networks introduces uncertainties that can substantially affect network reliability. It is crucial to implement appropriate measures to maintain reliability parameters within acceptable limits and ensure a stable power supply for consumers. This paper aims to optimize the location, size, and number of DG units to minimize active power losses and improve distribution System (DS) reliability while considering system operational constraints. To achieve this objective, multiple tests are conducted, and the particle swarm optimization (PSO) technique is implemented. The simulation studies are performed using the ETAP software 19.0.1 version, while the PSO algorithm is implemented in MATLAB R2018a. ETAP enables a comprehensive evaluation of the DG system’s performance, providing valuable insights into its effectiveness in reducing power losses and enhancing system reliability. The PSO algorithm in MATLAB ensures accurate optimization, facilitating the identification of the optimal DG unit location and size. This study uses a modified IEEE-13 bus unbalanced radial DS as the test system, assessing the effects of photovoltaic (PV) and wind DG units under various scenarios and penetration levels. The results demonstrate that the optimal DG unit location and size of either a single PV or wind DG unit significantly reduce power losses, improve DS reliability, and enable effective load sharing with the substation. Moreover, this study analyzes the impact of DG unit uncertainty on system performance. The findings underscore the potential of optimized DG integration to enhance DS efficiency and reliability in the presence of renewable energy sources.

Comparative Analysis and Evaluation of the Different Active Cell Balancing Topologies in Lithium Ions Batteries

Series connected batteries must have their cells balanced whenever charging and discharging to extend battery lifespans, assure safe operation, and increase battery pack useful capacity. It also causes charge imbalance issues, which will result in battery cell damage and battery life loss. Several charge/discharge equalization circuits have been suggested however, presently there has been no work regarding the comparison and evaluation of the speed and efficiencies in both modes. In this study, cell balancing on dc-to-dc buck-boost converter and interleaved flyback converter topologies operating in discontinuous current mode are analyzed, designed, and implemented. A simulation model of the converter-based topologies of an active cell balancing system is proposed and designed along with a power loss analysis, efficiencies, and control technique. With the purpose of establishing an energy storage application, the system’s cells are grouped into 8 series cells for SOC balancing and 2 series cells for voltage balancing circuit design. Power loss analysis is performed to analyze the efficiency of these two converter topologies to identify which system performs better. In SOC balancing in charging mode, the buck-boost and interleaved flyback converters’ power efficiencies are 85.596% and 65.1521% respectively and during voltage balancing 93.9078% and 73.1506% respectively.

A Multi-Inverter Multi-Rectifier Wireless Power Transfer System for Charging Stations With Power Loss Optimized Control

Electric vehicles (EVs) with different output power levels can use wireless power transfer (WPT) systems. Different vehicle assemblies (VAs) may be charged by different ground assemblies (GAs) in charging stations. However, the overall efficiency of the WPT system may drop significantly when the power class difference between GA and VA is large. To address this issue this paper proposes a DC-link parallel AC-link series (DPAS) multi-inverter multi-rectifier (MIMR) architecture for high-power WPT systems. Modulation, power transfer capability, and power sharing from the design aspects are investigated. A detailed power loss analysis and an easy-to-implemented power loss optimized control method based on mutual inductance identification are presented in this paper. Finally, experimental results are obtained from a 20-kW LCC-LCC WPT system to validate the analysis and proposed system operation.

Reliability evaluation of carrier‐based pulse width modulated three‐level F‐type neutral point clamped inverter with power loss analysis

AbstractAn improved carrier‐based pulse‐width‐modulation (CBPWM) technique for a three‐level (3L) F‐type neutral point‐clamped (FNPC) inverter is presented in this paper. By using the proposed modulation scheme, the DC‐link capacitor voltage at the neutral point is balanced. For manufacturers, reliability is one of the major concerns for all power electronics devices and parts. This paper proposes an extensive reliability analysis of the 3L‐FNPC inverter. Considering the mean time to failure (MTTF) of each device, the reliability of the 3L‐FNPC inverter is analyzed in this present work by using two different methods, which are the approximate method and the exact method. To compute the failure rate of the equipment, only the number of components is considered in the approximate method. Alternatively, exact methods are utilized to evaluate the reliability of a system by knowing the different stress levels and various operating environments of a specific system. Because of the strong correlation between device failure and temperature stress factors, power loss analysis is used in the exact method. The MATLAB Simulink environment is used to determine the power loss of the switching devices. A solar off‐grid photovoltaic (PV) system is considered for reliability testing. Experimental mission profile data are used to estimate the lifetime of the 3L‐FNPC inverter by applying the rainflow counting algorithm, the Coffin‐Manson model, and Miner's rule. The competitiveness, effectiveness, and reliability of the 3L‐FNPC inverter with the proposed modulation technique are validated using a hardware prototype.

An Effective Optimization Method and Implementation of Permanent Magnet Electrodynamic Wheel for Maglev Car

The levitation-propulsion integration ability of radial permanent magnet electrodynamic wheel (PM EDW) renders its competitive edge over other magnetic levitation systems. A low-cost and effective second induction method is proposed to target the synchronous improvement of the saturation speed, levitation and propulsion forces. Its effectiveness is determined from the small-scale EDW to the full-scale EDW via theoretical model, simulation analysis and experiments test. First, according to magnetic charge theory, an updated EDW is proposed and developed. Simulated and tested results of the small-scale EDW demonstrate that the levitation force, propulsion force and saturation speed are increased by 14%, 7% and 30%. This improvement benefits the increased induction current and the mitigated skin effect. Afterwards, further analysis of the full-scale EDW with rings of various conductivity and thickness is conducted. The levitation force, propulsion force and saturation speed are enhanced by more than 50%, 10% and 200% synchronously. Based on analysis of power loss under the same levitation and propulsion forces, the updated EDW is more efficient than the original EDW. Ultimately, a proof-of-principle prototype with the updated EDW and 4-m long guideway are developed. The multi-loop PID control strategy along with dynamic mode implementation methodology are introduced. The scaled prototype is levitated over guideway at 12 mm and the levitation-propulsion ability is implemented with the maximum acceleration of 1.25 m/s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . This proof-of-principle prototype with updated EDW and control strategy paves the way to engineering applications of Maglev car.

Implementation and reliability analysis of a new non‐isolated quadratic buck–boost converter using improved Markov modelling

AbstractHere, a new buck–boost converter with reliability analysis is proposed. The converter has utilized a new voltage multiplier cell at the input side to boost the output voltage. It has a continuous input current with a wide range of duty cycle operations. The converter achieves unity gain at 26.8% duty cycle and can also operate in continuous and discontinuous conduction modes in buck and boost modes. The detailed reliability analysis of the proposed converter using improved Markov modelling is also presented by considering both open circuit and short circuit faults across the semiconductor devices. The variation of reliability and the mean time to failure (MTTF) with different converter parameters like the duty cycle and the input voltage is also discussed here. The hardware results of the developed prototype converter are also presented here at varying duty ratios. The power loss analysis and comparison of the converter with other newly proposed buck–boost topologies show the advantages of the proposed converter. For checking the stability of the converter, the state space model of the converter is also discussed in detail of the proposed converter.

Power Loss Analysis with Dispersed Generation in Multifunction Power Conditioner Design to Improve Power Quality

The recent modification in utilizing Multifunction Power Conditioner (MPC) such as Unified Power Quality Conditioner devices in power systems has led to different degrees of power losses, owing to electronic power impacts. This paper presents a detailed comparison of power loss analysis in various configurations of MPC, that is, the conventional unified power quality conditioner (UPQC) and the UPQC with distributed generation (〖UPQC〗_DG). The independent losses based on inverter design and distributed generation interfacing to the distribution form the basis for each configuration case. The investigation considered conventional UPQC as the base case for power losses, and the study was extended to 〖UPQC〗_DG at steady state operating condition. In all configurations, Switching Losses (SL) and conduction losses were considered using simulation studies carried out in MATLAB/SIMULINK, and the results obtained in all cases were used for comparative studies. Finally, the outcome indicates that the losses in 〖UPQC〗_DG is more than conventional UPQC based on simulation results in all cases.

A Reduced Switch Count High-Frequency Single-Phase 5-L MLI for IH Applications

Nowadays, multilevel inverter (MLI)-based induction heating (IH) technology is the best-suited option in many domestic, commercial and medicinal applications because of its higher efficiency, low cost, fast heating and lower electromagnetic interference (EMI). This paper presents reduced components count high-frequency (HF) single phase five-level (5-L) MLI for IH applications. The working methodology of the proposed system has been analyzed in the multicarrier phase disposition pulse width modulation (MC-PD-PWM) method in high switching frequency i.e., 10[Formula: see text]kHz. In addition, the proposed topology can produce output voltage twice of input voltage without any external source. Moreover, the detailed power loss and reliability analysis have been evaluated for the proposed system. In terms of switch count and efficiency, the single-phase 5-L inverter architecture is compared to some conventional and current topologies. Finally, to validate and justify the operation of the proposed system, the simulation and experimental results of five-level inverter are presented.

An Integrated Three-Phase AC–DC Wireless-Power-Transfer Converter With Active Power Factor Correction Using Three Transmitter Coils

Three-phase AC-DC converters are more commonly used for high-power applications compared to single-phase converters. For high-power wireless power transfer (WPT) applications, such as wireless electric vehicle chargers, usually a two-stage topology is applied, which consists of a three-phase AC-DC rectifier with power factor correction and a DC-DC converter for WPT. Recently, there are several studies on three-phase single-stage WPT solutions being proposed to reduce power conversion stages, and furtherly increase overall efficiency and reduce system cost. In this paper, an integrated three-phase AC-DC WPT converter topology with active power factor correction is proposed. The count of power semiconductor devices is significantly reduced compared to state-of-the-art three-phase single-stage topologies. Moreover, three transmitter coils are used to enhance the system power capacity. Topology description, operation analysis, control method, power loss analysis, and reference design guideline of the proposed topology are presented in detail. Finally, a laboratory prototype is built and evaluated. The functionalities, performances, and advantages are demonstrated by the corresponding experimental results.

Reliability Assessment of Power Semiconductor Devices for a 13-Level Boost Inverter Topology

Since the last few decades, research on multilevel inverters (MLIs) has been growing in the power electronics field. The MLI is preferred over conventional two-level converters due to its improved performance. In recent years, different types of MLI architectures have been proposed, each employing a unique combination of power semiconductor devices to produce a multilevel output voltage waveform. The reliability of a multilevel inverter is a crucial performance indicator that must be taken into account at every stage from design to commercialization. MLI is vulnerable to a variety of failure modes and processes due to a large number of interdependent components. In this paper, a 13-level boost inverter topology has been analyzed and test results are presented and discussed. The analysis has been carried out in terms of open-circuit fault (OCF), short-circuit fault (SCF), power loss, and thermal analysis. The results have been discussed and recommendations have been made for the better design of the inverter topology to improve reliability.

Accurate Analysis Method and Voltage Gain Curve Derivation Algorithm Based on Time-Domain Analysis for High-Efficiency LLC Resonant Converter Design

An accurate analysis method for an LLC resonant converter and a time-domain analysis (TDA)-based voltage gain curve derivation algorithm are proposed in this paper. When applied to an LLC resonant converter, the TDA method can obtain high-accuracy current and voltage waveforms by solving nonlinear equations for circuit parameters through operation-mode analysis. An LLC resonant converter operating mode classification algorithm was proposed based on the results of this analysis. The circuit voltage and current values in the steady state were quickly and precisely derived using this algorithm. An accurate power-loss analysis is required to design a high-efficiency converter. Therefore, TDA is a powerful tool for designing an LLC resonant network. The proposed TDA-based LLC resonant converter analysis and voltage gain curve derivation algorithm provides high-accuracy voltage, current value estimation and voltage gain curves for all switching-frequency ranges. The effectiveness of the proposed algorithm is verified using a 500 W LLC resonant converter prototype experiment.

A single‐source switched‐capacitor based 13‐level sextuple boost inverter with reduced component count and low THD

AbstractA switched‐capacitor‐based 13‐level inverter with a lesser number of components is presented in this article. The 13‐level single‐phase AC output voltage is achieved with a voltage gain of 6 by including a single DC source, 11 switches, 4 capacitors, and 3 diodes in the proposed converter. The self‐voltage balancing is achieved for various types of load without the need for complex control schemes and auxiliary circuits. The proposed topology does not require a back‐end H‐bridge to generate negative polarity. This leads to a reduction in voltage stresses across the switches. Thus, total standing voltage (TSV) and the overall cost of the proposed topology are reduced as compared to the state‐of‐the‐art topologies reported in the literature. Furthermore, an Improved Nearest Level Modulation (INLM) scheme is used to improve the power quality of the output voltage. Using the proposed scheme, the Total Harmonic Distortion (THD) of the output voltage is reduced to 5.08%. The power loss analysis for various elements of the proposed converter is also included. A comparison with recent topologies in reference to various performance parameters is carried out. In addition to the simulation study, a laboratory prototype is prepared to validate the efficacy of the proposed converter.

A Triple Boost Seven-Level Common Ground Transformerless Inverter Topology for Grid-Connected Photovoltaic Applications

This article proposes a single-stage, seven-level (7L), switched-capacitor-based grid-connected inverter architecture with a common ground feature. This topology has the ability to boost the output voltage up to three times the input voltage. The proposed topology can diminish the leakage current in grid-connected photovoltaic (GC-PV) applications, and its capacitor voltages are self-balanced without any additional control strategies. The different operating modes are described in detail with their related mathematical expressions. The design of passive components and a detailed power loss analysis are presented. The merits of the proposed structure are demonstrated using a detailed comparative assessment. The grid-connected operation of the proposed inverter structure is simulated in the MATLAB/Simulink environment, and the results are presented. The laboratory prototype of 935 W is built and analyzed to validate the performance of the proposed structure.

Investigation and Simulation of Technical Power Losses on 33/11kv Distribution Feeders Based on Gauss-Seidel Iterative Approach

Loss of technical performance is one of the main causes of energy shortages and inefficient operation of electrical machines in energy systems. In this study, an analysis of power losses for six selected 33/11 kV distribution feeders was presented. (Kakoba, Ntare, Karamurani, Ishaka MbararaNorth1 and Mbarara North 2) at Mbarara Central Substation Network of UMEME Electricity Distribution Company in Uganda. Data such as cable type, conductor resistance, conductor reactance, and route length were obtained from energy suppliers. From this data, the Gauss-Seidel method was used to determine the total active power and associated reactive power of the entire substation system. The findings showed that the substation is profitable due to the small calculated total power losses. Although it is possible to reduce the total loss to at least 9-12%. Losses were due to old substations, overloaded transformers, and copper losses core losses in lengthy feeder routes. To improve the performance of power distribution networks, it was recommended to replace old conductors to reduce losses.

A Novel Multilevel Inverter With Self-Balancing Capability of Capacitors Voltage; Structure, Modulation, and Operation

This article presents a 17-level asymmetrical multilevel inverter (MLI) with a reduced number of components. This structure can also be used symmetrically to increase redundancy. It can be extended in a modular fashion to increase the number of output voltage levels. Moreover, the capacitor voltages are self-balanced and do not require a sensor to stabilize the voltage. Due to the application of a level-shifted modulation (LSM), most power switches are turned on and off at low and fundamental frequencies, which will significantly reduce losses. Other benefits of this topology are the inherent production of negative levels without H-bridge, reduced total standing voltage (TSV), and low total harmonic distortion (THD). Power loss analysis is also presented as well as calculation of capacitances. MATLAB simulation results and laboratory implementation are carried out to evaluate circuit performance in different operational conditions.

A Three-Phase Hybrid Multilevel Inverter With Enhanced Pulse-Width Modulation Strategy

This paper presents a three-phase hybrid multilevel inverter (MLI) with enhanced pulse-width modulation (PWM) strategy. The proposed hybrid MLI is developed based on the series connection of half-bridge and full-bridge for its level generation together with the T-type inverter for its polarity generation. The level and polarity generation circuits operate at high and fundamental frequencies respectively. An enhanced PWM strategy has been proposed to reduce the computational complexity and solve the high-frequency switching transitions issue in the existing hybrid MLI modulation method. The proposed MLI can produce 11 levels of line output voltage with reduced dc sources requirement. The detailed analyses which have been performed include the circuit configuration, operating principles and modeling, PWM signals generation, output voltage characteristics, dynamic response, harmonics content, power loss analysis and voltage stress of power switches. The results obtained from simulation and experiments verified the operating principle and functionality of the proposed hybrid MLI.