Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077319
Neha Vashisth, Rajeev Gupta
This paper studies different variants of hard-switched and soft-switched buck-boost converters. Detailed analysis of different hard-switched and soft-switched buck-boost converter has been provided in the paper. Design of two-loop control of buck-boost converter has also been provided in this paper. Simulation results obtained collaborate with the theoretical results.
{"title":"A study of different hard-switched and soft-switched variants of buck-boost converter","authors":"Neha Vashisth, Rajeev Gupta","doi":"10.1109/POWERI.2016.8077319","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077319","url":null,"abstract":"This paper studies different variants of hard-switched and soft-switched buck-boost converters. Detailed analysis of different hard-switched and soft-switched buck-boost converter has been provided in the paper. Design of two-loop control of buck-boost converter has also been provided in this paper. Simulation results obtained collaborate with the theoretical results.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114494575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077418
S. Pradhan, Ikhlaq Hussain, Bhim Singh, B. K. Panigrahi
An improved performance of a 3-phase grid integrated solar photovoltaic (PV) system is presented by incorporating a hybrid fractional normalized least mean square (FNLMS) algorithm with an appropriate maximum power point tracking (MPPT) method. The adopted 3-phase, 3-wire, single stage grid system consists of PV array, filters, loads, and a 3-leg voltage source converter (VSC) with a DC link capacitor. The system with this FNLMS adaptive control algorithm seeks to achieve the objectives of unity power factor (UPF) at the source end, load balancing and reduced total harmonic distortion (THD). These objectives are accomplished by generating controlled switching pulses for the insulated gate bipolar transistor (IGBT) based VSC using hybrid FNLMS algorithm. The efficiency of the proposed algorithm is verified with experimental prototype developed in the laboratory.
{"title":"A hybrid FNLMS approach to improve the performance of a grid integrated solar PV system","authors":"S. Pradhan, Ikhlaq Hussain, Bhim Singh, B. K. Panigrahi","doi":"10.1109/POWERI.2016.8077418","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077418","url":null,"abstract":"An improved performance of a 3-phase grid integrated solar photovoltaic (PV) system is presented by incorporating a hybrid fractional normalized least mean square (FNLMS) algorithm with an appropriate maximum power point tracking (MPPT) method. The adopted 3-phase, 3-wire, single stage grid system consists of PV array, filters, loads, and a 3-leg voltage source converter (VSC) with a DC link capacitor. The system with this FNLMS adaptive control algorithm seeks to achieve the objectives of unity power factor (UPF) at the source end, load balancing and reduced total harmonic distortion (THD). These objectives are accomplished by generating controlled switching pulses for the insulated gate bipolar transistor (IGBT) based VSC using hybrid FNLMS algorithm. The efficiency of the proposed algorithm is verified with experimental prototype developed in the laboratory.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128279142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077329
R. Ahuja, T. Maity, Sushma Kakkar
Distributed generation (DG) is experiencing a rapid development as a new means of power generation. Power electronics systems can account for a significant part of the total capital cost of a typical DG system. In grid-connected DG systems, single-phase or three-phase pulse width modulation (PWM) voltage-source inverters (VSIs) are often used for synchronizing the utility grid with DG source in order to (i) regulate active reactive power control through voltage and frequency control (ii) power quality improvement. The current control of the grid-connected inverters plays a predominant role in feeding a grid with high quality power. In this paper, ANFIS control scheme is investigated to control active and reactive power fed into grid through three phase voltage source inverter to enhance the power quality and increase the dynamic performance. The average power control method provides high quality sinusoidal output current and controls the average power flow. ANFIS current controller is used to track reference current. The studied system is modeled and simulated in the MATLAB/Simulink environment and the results obtained are compared with conventional PI controller. The ANFIS based control shows better performance compared to PI current controller.
{"title":"Control of active and reactive power of grid connected inverter using adaptive network based fuzzy inference system (ANFIS)","authors":"R. Ahuja, T. Maity, Sushma Kakkar","doi":"10.1109/POWERI.2016.8077329","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077329","url":null,"abstract":"Distributed generation (DG) is experiencing a rapid development as a new means of power generation. Power electronics systems can account for a significant part of the total capital cost of a typical DG system. In grid-connected DG systems, single-phase or three-phase pulse width modulation (PWM) voltage-source inverters (VSIs) are often used for synchronizing the utility grid with DG source in order to (i) regulate active reactive power control through voltage and frequency control (ii) power quality improvement. The current control of the grid-connected inverters plays a predominant role in feeding a grid with high quality power. In this paper, ANFIS control scheme is investigated to control active and reactive power fed into grid through three phase voltage source inverter to enhance the power quality and increase the dynamic performance. The average power control method provides high quality sinusoidal output current and controls the average power flow. ANFIS current controller is used to track reference current. The studied system is modeled and simulated in the MATLAB/Simulink environment and the results obtained are compared with conventional PI controller. The ANFIS based control shows better performance compared to PI current controller.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128349738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077248
N. Chaudhari, Trupti P. Hinge, S. Dambhare
False tripping of distance relays on load encroachment may lead to cascade tripping and subsequent blackouts. Hence relays should be supervised to avoid tripping on load encroachment. In this paper, an algorithm based on Decision Tree (DT) is proposed for the differentiation of load encroachment from fault. DT is formulated using Transient Stability Margin (TSM) of generator angles as an attribute. The distance relay is supervised with the decision from DT to avoid tripping on load encroachment. Case Studies are presented on IEEE New England 39 bus system using DIgSILENT PowerFactory software. The simulated results proves the effectiveness of the proposed scheme.
{"title":"Blocking of distance relays zone3 under load encroachment conditions using decision tree technique","authors":"N. Chaudhari, Trupti P. Hinge, S. Dambhare","doi":"10.1109/POWERI.2016.8077248","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077248","url":null,"abstract":"False tripping of distance relays on load encroachment may lead to cascade tripping and subsequent blackouts. Hence relays should be supervised to avoid tripping on load encroachment. In this paper, an algorithm based on Decision Tree (DT) is proposed for the differentiation of load encroachment from fault. DT is formulated using Transient Stability Margin (TSM) of generator angles as an attribute. The distance relay is supervised with the decision from DT to avoid tripping on load encroachment. Case Studies are presented on IEEE New England 39 bus system using DIgSILENT PowerFactory software. The simulated results proves the effectiveness of the proposed scheme.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"1 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124208200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077207
R. Ramkumar, C. Sugumaran
Polymer plays a major role in the engineering applications. Though its usage is having major environmental issues, researchers still focusing on effective usage of polymers with respect to its abundance in availability, flexibility in processing, cost effectiveness and it also exhibits 30% – 40% operating life time of the costly other materials. Polymers by nature have low thermal conductivity and low dielectric constant which are non-favored properties for electrical applications. Recent researches involves in the identification of additives which helps to enhance the properties of polymers. Nano additives such as ceramics or metal oxide powder show the improvement in the properties of polymers. In this work a most commonly used polymer, High density polyethylene (HDPE) is considered for analysis. It is observed that when HDPE blended with Alumina (Al2O3) nano fillers at different weight percentage results in enhancement of Electrical properties. Finally, a conclusion is arrived that at 3 wt % Alumina with HDPE is having higher Capacitance value and at 5 wt % Alumina with HDPE is having better dielectric strength.
{"title":"Investigation on dielectric properties of HDPE with alumina nano fillers","authors":"R. Ramkumar, C. Sugumaran","doi":"10.1109/POWERI.2016.8077207","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077207","url":null,"abstract":"Polymer plays a major role in the engineering applications. Though its usage is having major environmental issues, researchers still focusing on effective usage of polymers with respect to its abundance in availability, flexibility in processing, cost effectiveness and it also exhibits 30% – 40% operating life time of the costly other materials. Polymers by nature have low thermal conductivity and low dielectric constant which are non-favored properties for electrical applications. Recent researches involves in the identification of additives which helps to enhance the properties of polymers. Nano additives such as ceramics or metal oxide powder show the improvement in the properties of polymers. In this work a most commonly used polymer, High density polyethylene (HDPE) is considered for analysis. It is observed that when HDPE blended with Alumina (Al2O3) nano fillers at different weight percentage results in enhancement of Electrical properties. Finally, a conclusion is arrived that at 3 wt % Alumina with HDPE is having higher Capacitance value and at 5 wt % Alumina with HDPE is having better dielectric strength.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121199212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077219
S. Mishra, S. Purwar, N. Kishor
This paper proposes a fuzzy logic controller (FLC) for oscillating water column (OWC) wave energy plant in order to prevent the Wells turbine stalling. The stalling phenomenon decreases turbine efficiency when subjected to high airflow rate inside the OWC. Thus, the turbine needs to be operated within the permissible flow coefficient range so as to obtain maximum energy from the plant. The turbine is coupled to a wound rotor induction generator (WRIG) in series with externally connected rotor resistances. An adequate control scheme is required for choosing rotor resistance values which in turn will change the rotor slip. The FLC scheme with mean airflow velocity as input and resistance values as output has been designed. The fuzzy rules have been defined based on input-output data. The input-output data of the controller is obtained by numerical analysis of the plant for a predefined range of turbine flow coefficient and regular waves. The performance of proposed controller is demonstrated under regular and irregular sea wave conditions.
{"title":"Fuzzy logic control of OWC wave energy plant for preventing wells turbine stalling","authors":"S. Mishra, S. Purwar, N. Kishor","doi":"10.1109/POWERI.2016.8077219","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077219","url":null,"abstract":"This paper proposes a fuzzy logic controller (FLC) for oscillating water column (OWC) wave energy plant in order to prevent the Wells turbine stalling. The stalling phenomenon decreases turbine efficiency when subjected to high airflow rate inside the OWC. Thus, the turbine needs to be operated within the permissible flow coefficient range so as to obtain maximum energy from the plant. The turbine is coupled to a wound rotor induction generator (WRIG) in series with externally connected rotor resistances. An adequate control scheme is required for choosing rotor resistance values which in turn will change the rotor slip. The FLC scheme with mean airflow velocity as input and resistance values as output has been designed. The fuzzy rules have been defined based on input-output data. The input-output data of the controller is obtained by numerical analysis of the plant for a predefined range of turbine flow coefficient and regular waves. The performance of proposed controller is demonstrated under regular and irregular sea wave conditions.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116337951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077387
S. Arvind, R. Akshay, A. Sreedevi
Sliding Mode Control (SMC) is a robust and easy to design control law, which can be applied to linear and nonlinear systems. It has been of great research interest for applications in power electronics and motor drives. Conventional/First order sliding mode suffers from chattering of the control input, which when used for DC-DC Converters, results in variable switching frequency of the power switch. This will lead to more switching losses and also makes the design of the converter passives difficult. This research work presents a modified version of SMC, called Constant Frequency SMC (CFSMC), which ensures that DC-DC Converters operate at constant switching frequency and yet remain as robust and easy to implement as the conventional SMC. The theory is developed and verified through simulations for Boost, Buck-Boost, SEPIC and Cuk Converters in MATLAB/SIMULINK.
{"title":"A novel constant frequency sliding mode control of DC-DC converters","authors":"S. Arvind, R. Akshay, A. Sreedevi","doi":"10.1109/POWERI.2016.8077387","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077387","url":null,"abstract":"Sliding Mode Control (SMC) is a robust and easy to design control law, which can be applied to linear and nonlinear systems. It has been of great research interest for applications in power electronics and motor drives. Conventional/First order sliding mode suffers from chattering of the control input, which when used for DC-DC Converters, results in variable switching frequency of the power switch. This will lead to more switching losses and also makes the design of the converter passives difficult. This research work presents a modified version of SMC, called Constant Frequency SMC (CFSMC), which ensures that DC-DC Converters operate at constant switching frequency and yet remain as robust and easy to implement as the conventional SMC. The theory is developed and verified through simulations for Boost, Buck-Boost, SEPIC and Cuk Converters in MATLAB/SIMULINK.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116356038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077220
Srinivas Pratapgiri
The phase inductance of Switched Reluctance Motor (SRM) is a function of position and stator current. To predict the performance of the motor an accurate model is required. This paper deals with modeling and analysis of Switched Reluctance Motor with Three Term Inductance model. In Three-Term Inductance method, the motor is modeled by estimating the inductance at three different positions of the rotor i.e aligned position, misaligned position and unaligned position. These inductances are evaluated through Finite Element Analysis (FEA). The Non-linear model of motor is developed in SIMULINK and performance with Hysteresis Current Control is analyzed.
{"title":"Hysteresis current control of switched reluctance motor using three term inductance model","authors":"Srinivas Pratapgiri","doi":"10.1109/POWERI.2016.8077220","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077220","url":null,"abstract":"The phase inductance of Switched Reluctance Motor (SRM) is a function of position and stator current. To predict the performance of the motor an accurate model is required. This paper deals with modeling and analysis of Switched Reluctance Motor with Three Term Inductance model. In Three-Term Inductance method, the motor is modeled by estimating the inductance at three different positions of the rotor i.e aligned position, misaligned position and unaligned position. These inductances are evaluated through Finite Element Analysis (FEA). The Non-linear model of motor is developed in SIMULINK and performance with Hysteresis Current Control is analyzed.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121451305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077397
G. Ghosh, K. Vasudevan, N. Lakshminarasamma
Non-sinusoidal magnetic induction variation pattern (IVP) makes the estimation of iron loss a challenging step of designing a trapezoidal back-EMF machine. Commercially available finite element analysis (FEA) based machine design tools fail to accurately estimate core losses in such situations. Previously proposed methods to address that problem either compromise too much on accuracy, or are too time-consuming to be applied to every design-iteration. This paper proposes a simple theoretical approach to address this problem. Flux density variations under both no-load and loaded conditions were studied and their relations with the machine's design details were derived. The complete approach was verified by 2D time stepped FEA. The loss expressions presented were verified by experiments on a sample material.
{"title":"Theoretical estimation of core loss in a trapezoidal Back-EMF motor","authors":"G. Ghosh, K. Vasudevan, N. Lakshminarasamma","doi":"10.1109/POWERI.2016.8077397","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077397","url":null,"abstract":"Non-sinusoidal magnetic induction variation pattern (IVP) makes the estimation of iron loss a challenging step of designing a trapezoidal back-EMF machine. Commercially available finite element analysis (FEA) based machine design tools fail to accurately estimate core losses in such situations. Previously proposed methods to address that problem either compromise too much on accuracy, or are too time-consuming to be applied to every design-iteration. This paper proposes a simple theoretical approach to address this problem. Flux density variations under both no-load and loaded conditions were studied and their relations with the machine's design details were derived. The complete approach was verified by 2D time stepped FEA. The loss expressions presented were verified by experiments on a sample material.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"2015 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127700753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2016-11-01DOI: 10.1109/POWERI.2016.8077393
M. Siddique, A. Sarwar
Multilevel Inverters (MLI) are used in electrical drives in industries especially for medium/high power applications due to the low total harmonic distortion (THD) contents in voltage waveform and high utilization factor. For control of output voltage several pulse width modulation techniques are used. Carrier based PWM (CBPWM) techniques are quite simple compared to space vector modulation. In this paper diode clamped MLI has been selected and its performance with several conventional CBPWM techniques has been analyzed using MATLAB simulation. The analysis is based on four different reference signals taken with carrier wave. The variation of THD with amplitude modulation index is shown for all CBPWM technique. Gate signal generation for all the CBPWM techniques using TMS320F28335 has also been included in this paper.
{"title":"Performance analysis of carrier based PWM technique for three level diode clamped multilevel inverter with different reference signals","authors":"M. Siddique, A. Sarwar","doi":"10.1109/POWERI.2016.8077393","DOIUrl":"https://doi.org/10.1109/POWERI.2016.8077393","url":null,"abstract":"Multilevel Inverters (MLI) are used in electrical drives in industries especially for medium/high power applications due to the low total harmonic distortion (THD) contents in voltage waveform and high utilization factor. For control of output voltage several pulse width modulation techniques are used. Carrier based PWM (CBPWM) techniques are quite simple compared to space vector modulation. In this paper diode clamped MLI has been selected and its performance with several conventional CBPWM techniques has been analyzed using MATLAB simulation. The analysis is based on four different reference signals taken with carrier wave. The variation of THD with amplitude modulation index is shown for all CBPWM technique. Gate signal generation for all the CBPWM techniques using TMS320F28335 has also been included in this paper.","PeriodicalId":332286,"journal":{"name":"2016 IEEE 7th Power India International Conference (PIICON)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125585105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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