Pub Date : 2020-02-01DOI: 10.1109/PIICON49524.2020.9112960
C. Prasad, M. Biswal, P. K. Nayak
In this paper, swarm assisted positive sequence current based directional relaying is proposed for detection and direction estimation of faults in power transmission network. For this classification, two different thresholds are identified through particle swarm optimization (PSO) algorithm. The available methods used to adopt trial-and-error based threshold setting approaches for detection and classification of fault direction and have limitation for certain fault and non-fault events. On the other hand, the proposed swarm intelligence assisted optimal threshold setting obtained from a set of randomly generated solutions using PSO ensures reliable estimation of fault direction even for extreme fault and non-fault events. This is evident from the extensive case studies generated on a 2-bus test power system using MATLAB-SIMULINK.
{"title":"Swarm Assisted Positive Sequence Current Component based Directional Relaying for Transmission Line Protection","authors":"C. Prasad, M. Biswal, P. K. Nayak","doi":"10.1109/PIICON49524.2020.9112960","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9112960","url":null,"abstract":"In this paper, swarm assisted positive sequence current based directional relaying is proposed for detection and direction estimation of faults in power transmission network. For this classification, two different thresholds are identified through particle swarm optimization (PSO) algorithm. The available methods used to adopt trial-and-error based threshold setting approaches for detection and classification of fault direction and have limitation for certain fault and non-fault events. On the other hand, the proposed swarm intelligence assisted optimal threshold setting obtained from a set of randomly generated solutions using PSO ensures reliable estimation of fault direction even for extreme fault and non-fault events. This is evident from the extensive case studies generated on a 2-bus test power system using MATLAB-SIMULINK.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127206046","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 : 2020-02-01DOI: 10.1109/piicon49524.2020.9112981
{"title":"PIICON 2020 Front Matters","authors":"","doi":"10.1109/piicon49524.2020.9112981","DOIUrl":"https://doi.org/10.1109/piicon49524.2020.9112981","url":null,"abstract":"","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125054880","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9113035
R. Singh, S. Bose, P. Dwivedi
In today’s scenario, Conventional resources are limited and practice followed for electrical power generation has a fetal effect on the environment, which forced us to seek alternatives. The renewable energy, specially Photovoltaic (PV) sources seem to be a solution for it. As the PV sources are integrated into the grid through converters. Hence, power electronic converters have emerged as an integral part of renewable energy generation systems for generating electrical energy. In this paper, Type 2 based closed-loop control analysis of flyback converter with PV as a source along with Maximum Power Point Tracking (MPPT) is done. Type 2 compensation makes the close loop control of the system sturdy for all the variations occured in the system. The proposed technique is simulated in MATLAB/SIMULINK and the results are analyzed.
{"title":"Closed Loop Control of Flyback Converter with PV as a Source","authors":"R. Singh, S. Bose, P. Dwivedi","doi":"10.1109/PIICON49524.2020.9113035","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9113035","url":null,"abstract":"In today’s scenario, Conventional resources are limited and practice followed for electrical power generation has a fetal effect on the environment, which forced us to seek alternatives. The renewable energy, specially Photovoltaic (PV) sources seem to be a solution for it. As the PV sources are integrated into the grid through converters. Hence, power electronic converters have emerged as an integral part of renewable energy generation systems for generating electrical energy. In this paper, Type 2 based closed-loop control analysis of flyback converter with PV as a source along with Maximum Power Point Tracking (MPPT) is done. Type 2 compensation makes the close loop control of the system sturdy for all the variations occured in the system. The proposed technique is simulated in MATLAB/SIMULINK and the results are analyzed.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114915175","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9112873
K. Kumari, Swagata Mapa, R. Maheshwari
Multilevel converters are widely used for its significant benefit of low harmonics and reduced switching losses compared to two-level converter. This paper presents a comparative evaluation of loss of two three-level inverter topologies, namely Neutral Point Clamped Converter (NPC) and T-type converter. The loss analysis are done for both topologies based on different devices like Silicon (Si), Silicon Carbide (SiC) and Gallium Nitride (GaN). Loss breakdown analysis for each switches and diodes in both topology are presented for different switching frequency and loading condition. Evaluation is mainly done with the help of MATLAB, and LTSpice. Comparison of losses for different switching frequency for different switches are done for both topologies. The result of loss estimation obtained from simulation and m-file is approximately the same. The result shows that GaN and SiC based converter is more efficient than Si based NPC and T-Type converter.
{"title":"Loss Analysis of NPC and T-Type Three-Level Converter for Si, SiC, and GaN based Devices","authors":"K. Kumari, Swagata Mapa, R. Maheshwari","doi":"10.1109/PIICON49524.2020.9112873","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9112873","url":null,"abstract":"Multilevel converters are widely used for its significant benefit of low harmonics and reduced switching losses compared to two-level converter. This paper presents a comparative evaluation of loss of two three-level inverter topologies, namely Neutral Point Clamped Converter (NPC) and T-type converter. The loss analysis are done for both topologies based on different devices like Silicon (Si), Silicon Carbide (SiC) and Gallium Nitride (GaN). Loss breakdown analysis for each switches and diodes in both topology are presented for different switching frequency and loading condition. Evaluation is mainly done with the help of MATLAB, and LTSpice. Comparison of losses for different switching frequency for different switches are done for both topologies. The result of loss estimation obtained from simulation and m-file is approximately the same. The result shows that GaN and SiC based converter is more efficient than Si based NPC and T-Type converter.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116026530","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9113038
A. Gangwar, Bhunesh Rathore, Om Prakash Mahela
In this paper, shunt fault is detected, classified and located in power transmission line. The synchronized Current signals at both the bus of the transmission line are used for obtaining approximate coefficients using wavelet transform. The proposed algorithm is used K-means clustering to detect and classify the faults. Fault location is estimated using linear regression method. The approximate wavelet coefficients of the both the buses are added to get resultant approximate coefficients. K-means clustering is applied on these resultant approximate coefficients to computes two centroid in a half cycle. The centroid difference (C.D) is computed, and the basis of the centroid difference the fault is detected and classified. Various case studies such as vary fault location, fault incidence angle and fault impedance to verify the robustness of the algorithm.
{"title":"K-means Clustering and Linear Regression Based Protection Scheme for Transmission Line","authors":"A. Gangwar, Bhunesh Rathore, Om Prakash Mahela","doi":"10.1109/PIICON49524.2020.9113038","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9113038","url":null,"abstract":"In this paper, shunt fault is detected, classified and located in power transmission line. The synchronized Current signals at both the bus of the transmission line are used for obtaining approximate coefficients using wavelet transform. The proposed algorithm is used K-means clustering to detect and classify the faults. Fault location is estimated using linear regression method. The approximate wavelet coefficients of the both the buses are added to get resultant approximate coefficients. K-means clustering is applied on these resultant approximate coefficients to computes two centroid in a half cycle. The centroid difference (C.D) is computed, and the basis of the centroid difference the fault is detected and classified. Various case studies such as vary fault location, fault incidence angle and fault impedance to verify the robustness of the algorithm.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122693068","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9112955
Kundan Kumar, Ramswaroop Ramswaroop, L. Yadav, Puneet Joshi, Medha Joshi
RES based DGs have gained popularity due to depletion of fossil reserves, increase demand (i.e. industrial growth, urbanization etc.). DG comprises of low generating capacity units installed near load dispatch centers. To provide the necessary active power RESs are also employed for providing reactive power support but it greatly varies with the type of DG units. That is why DGs are characterized in four major types based on real & imaginary power delivery capability. Installing an appropriate capacity at the most suitable bus is a nonlinear & nonconvex optimization problem. When optimally sited & sized RES minimize Preal loss & also improve voltage profile of the network. This artificial process hybrid of Particle Swarm Optimization (PSO) algorithm and Grey Wolf Optimization (GWO) algorithm for optimum allocating and sizing of Type-1 & Type- 2 DGs. This hybrid approach is applied and tested on IEEE 33 & IEEE 69 bus to achieve power loss minimization.
{"title":"Optimal Planning of Distributed Generation using Hybrid Metaheuristic Approach","authors":"Kundan Kumar, Ramswaroop Ramswaroop, L. Yadav, Puneet Joshi, Medha Joshi","doi":"10.1109/PIICON49524.2020.9112955","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9112955","url":null,"abstract":"RES based DGs have gained popularity due to depletion of fossil reserves, increase demand (i.e. industrial growth, urbanization etc.). DG comprises of low generating capacity units installed near load dispatch centers. To provide the necessary active power RESs are also employed for providing reactive power support but it greatly varies with the type of DG units. That is why DGs are characterized in four major types based on real & imaginary power delivery capability. Installing an appropriate capacity at the most suitable bus is a nonlinear & nonconvex optimization problem. When optimally sited & sized RES minimize Preal loss & also improve voltage profile of the network. This artificial process hybrid of Particle Swarm Optimization (PSO) algorithm and Grey Wolf Optimization (GWO) algorithm for optimum allocating and sizing of Type-1 & Type- 2 DGs. This hybrid approach is applied and tested on IEEE 33 & IEEE 69 bus to achieve power loss minimization.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122699351","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9112951
Kasimala Venkatanagaraju, M. Biswal
Zone-3 unit of conventional distance relay is vulnerable to voltage instability and load-encroachment which are known as system stress conditions. For such conditions, the impedance trajectory encroaches zone-3 reach. Based on the setting parameters of the relay, it is identified as a fault and relay may maloperate. However, the relay may maloperate for any three-phase fault during such stress events as the change in system parameters are identical for both the conditions. Zone-3 maloperation is the root cause behind 2012 Indian blackout. So, it is necessary to introduce a supporting algorithm to avoid relay maloperations and to curtail the occurrence of any blackout. This paper introduces windowed-Prony method to detect and discriminate fault from system stress conditions. This method will be activated when the impedance trajectory enters the setting zone-3 region. It is used to approximate the input signal and to estimate the error existing between actual and approximated signals. The squared error is considered as a fault detection index (FDI). The performance of this method is tested on IEEE 39 bus test system.
{"title":"Prevention of Power System Blackouts Using Windowed-Prony Method","authors":"Kasimala Venkatanagaraju, M. Biswal","doi":"10.1109/PIICON49524.2020.9112951","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9112951","url":null,"abstract":"Zone-3 unit of conventional distance relay is vulnerable to voltage instability and load-encroachment which are known as system stress conditions. For such conditions, the impedance trajectory encroaches zone-3 reach. Based on the setting parameters of the relay, it is identified as a fault and relay may maloperate. However, the relay may maloperate for any three-phase fault during such stress events as the change in system parameters are identical for both the conditions. Zone-3 maloperation is the root cause behind 2012 Indian blackout. So, it is necessary to introduce a supporting algorithm to avoid relay maloperations and to curtail the occurrence of any blackout. This paper introduces windowed-Prony method to detect and discriminate fault from system stress conditions. This method will be activated when the impedance trajectory enters the setting zone-3 region. It is used to approximate the input signal and to estimate the error existing between actual and approximated signals. The squared error is considered as a fault detection index (FDI). The performance of this method is tested on IEEE 39 bus test system.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"326 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122708325","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9113037
Sagnik Kumar, G. Narayanan, R. Muralidharan
Magnetic field sensing is important in many power electronic and motor control applications. By exploiting the capabilities of emerging wide band-gap materials and structures, such as AlGaN/GaN heterojunctions, high-performance magnetic field sensors can be realised. Such sensors can be used for reliable field sensing at extreme temperatures. A Hall sensing element typically generates a low-magnitude output voltage with a relatively large offset due to non-uniformities and stresses in the sensing element. In this work, an electronic subsystem is designed, fabricated and calibrated, whereby the method of current spinning is used alongside a signal conditioning network to cancel the effect of these offsets.
{"title":"Current Spinning and Signal Conditioning Circuit for High-Performance Magnetic Field Sensing","authors":"Sagnik Kumar, G. Narayanan, R. Muralidharan","doi":"10.1109/PIICON49524.2020.9113037","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9113037","url":null,"abstract":"Magnetic field sensing is important in many power electronic and motor control applications. By exploiting the capabilities of emerging wide band-gap materials and structures, such as AlGaN/GaN heterojunctions, high-performance magnetic field sensors can be realised. Such sensors can be used for reliable field sensing at extreme temperatures. A Hall sensing element typically generates a low-magnitude output voltage with a relatively large offset due to non-uniformities and stresses in the sensing element. In this work, an electronic subsystem is designed, fabricated and calibrated, whereby the method of current spinning is used alongside a signal conditioning network to cancel the effect of these offsets.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129559806","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9112945
R. Kumar, Raj Kumar, S. Marwaha, Bhim Singh
Power quality (PQ) disturbance issues have been increased because of several power converters utilized in the interfacing of renewable energy sources with the grid. Meanwhile, these PQ disturbances needs to be detected with an effective signal processing technique. PQ disturbances such as harmonics which persist in the power system network mostly, when multiply with the single stage PQ disturbances results into multiple PQ disturbances. On the contrary, one PQ disturbance followed by another PQ disturbance before the restoration of former disturbance depicts the case of multistage PQ disturbance. Several versions of S-Transform have been presented in this paper to control the gaussian window width by optimal tuning of window parameters. This paper proposes standard S-Transform based analysis of multiple and multistage PQ disturbances. For the simulation purpose, the synthetic data of these disturbances are generated based on IEEE-1159 standard in MATLAB environment. Effective results have been attained using the proposed algorithm.
{"title":"S-Transform Based Detection of Multiple and Multistage Power Quality Disturbances","authors":"R. Kumar, Raj Kumar, S. Marwaha, Bhim Singh","doi":"10.1109/PIICON49524.2020.9112945","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9112945","url":null,"abstract":"Power quality (PQ) disturbance issues have been increased because of several power converters utilized in the interfacing of renewable energy sources with the grid. Meanwhile, these PQ disturbances needs to be detected with an effective signal processing technique. PQ disturbances such as harmonics which persist in the power system network mostly, when multiply with the single stage PQ disturbances results into multiple PQ disturbances. On the contrary, one PQ disturbance followed by another PQ disturbance before the restoration of former disturbance depicts the case of multistage PQ disturbance. Several versions of S-Transform have been presented in this paper to control the gaussian window width by optimal tuning of window parameters. This paper proposes standard S-Transform based analysis of multiple and multistage PQ disturbances. For the simulation purpose, the synthetic data of these disturbances are generated based on IEEE-1159 standard in MATLAB environment. Effective results have been attained using the proposed algorithm.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128752271","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 : 2020-02-01DOI: 10.1109/PIICON49524.2020.9112950
Abhijeet Choudhury, S. Mohanty, S. Pati, S. Kar, Shantanu Kumar Mahalik, Rumeet Kumar Swain
This work is based on the integration and power control of a wind micro hydro hybrid autonomous system. The system comprises of a self excited induction generator based micro hydro system and a DFIG based wind power generation system which are integrated using a Sliding Mode Controller based Nine Switch Converter. The NSC controls the voltage both on the Rotor Side and the Stator Side of the DFIG. The DC link of the NSC houses a Battery Energy Storage System to provide active power support to the system. The reactive power support is provided through the terminals which are connected to the stator side of the DFIG. A Sliding Mode Controller is designed and implemented for robust power control of the system. The performance of the system is evaluated by subjecting the system to three different types of Local time varying loads i.e. Linear Load, Non-Linear Load and Dynamic Load. The above system is simulated and validated using MATLAB/Simulink environment.
{"title":"Integration and Control of a Hybrid Isolated System using SMC based Nine Switch Converter","authors":"Abhijeet Choudhury, S. Mohanty, S. Pati, S. Kar, Shantanu Kumar Mahalik, Rumeet Kumar Swain","doi":"10.1109/PIICON49524.2020.9112950","DOIUrl":"https://doi.org/10.1109/PIICON49524.2020.9112950","url":null,"abstract":"This work is based on the integration and power control of a wind micro hydro hybrid autonomous system. The system comprises of a self excited induction generator based micro hydro system and a DFIG based wind power generation system which are integrated using a Sliding Mode Controller based Nine Switch Converter. The NSC controls the voltage both on the Rotor Side and the Stator Side of the DFIG. The DC link of the NSC houses a Battery Energy Storage System to provide active power support to the system. The reactive power support is provided through the terminals which are connected to the stator side of the DFIG. A Sliding Mode Controller is designed and implemented for robust power control of the system. The performance of the system is evaluated by subjecting the system to three different types of Local time varying loads i.e. Linear Load, Non-Linear Load and Dynamic Load. The above system is simulated and validated using MATLAB/Simulink environment.","PeriodicalId":422853,"journal":{"name":"2020 IEEE 9th Power India International Conference (PIICON)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128315967","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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