Pub Date : 2019-05-30DOI: 10.1109/PEPQA.2019.8851539
D. Montenegro, M. Bello, R. Dugan, J. Taylor, Jeff Smith
Distribution power systems are evolving due to the incorporation of emerging technologies such as intelligent electronic devices, smart inverters and distributed energy resources requiring distribution engineers to have access to power system analysis tools that support the changing design and time-based features of such systems. The power system analysis tools should harmonize the new technologies in a way that autonomous and interconnected systems can be automated, simultaneously operated and visualized for maximum grid benefit by distribution engineers.Classic analysis based on static snapshots of loading is an inadequate practice for scheduling future investments in distribution systems and distribution management systems. This is a common practice that has been used for decades to maintain power systems over time. However, the needs of future systems require the integration of modern computing technologies and interfaces with advanced distribution system analysis. This accelerates the analysis and providing to the distribution engineer the information to make the right choice.In this paper, we discuss the needs mentioned above, and propose a flexible framework to support the development of distribution systems analysis. This multidisciplinary framework is supported by a set of open source tools developed by EPRI and other parties for presenting a modular approach to enable the next generation of distribution system analysis tools. These tools have been developed to advance the capabilities EPRI’s Open Source Distribution System Simulator OpenDSS to guide the industry on the distribution power system analysis tools and techniques.
{"title":"Evolving the Next Generation of Distribution Analysis Tools","authors":"D. Montenegro, M. Bello, R. Dugan, J. Taylor, Jeff Smith","doi":"10.1109/PEPQA.2019.8851539","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851539","url":null,"abstract":"Distribution power systems are evolving due to the incorporation of emerging technologies such as intelligent electronic devices, smart inverters and distributed energy resources requiring distribution engineers to have access to power system analysis tools that support the changing design and time-based features of such systems. The power system analysis tools should harmonize the new technologies in a way that autonomous and interconnected systems can be automated, simultaneously operated and visualized for maximum grid benefit by distribution engineers.Classic analysis based on static snapshots of loading is an inadequate practice for scheduling future investments in distribution systems and distribution management systems. This is a common practice that has been used for decades to maintain power systems over time. However, the needs of future systems require the integration of modern computing technologies and interfaces with advanced distribution system analysis. This accelerates the analysis and providing to the distribution engineer the information to make the right choice.In this paper, we discuss the needs mentioned above, and propose a flexible framework to support the development of distribution systems analysis. This multidisciplinary framework is supported by a set of open source tools developed by EPRI and other parties for presenting a modular approach to enable the next generation of distribution system analysis tools. These tools have been developed to advance the capabilities EPRI’s Open Source Distribution System Simulator OpenDSS to guide the industry on the distribution power system analysis tools and techniques.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"173 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133629967","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 : 2019-05-30DOI: 10.1109/PEPQA.2019.8851565
Edwin Herlyt Lopera-Mazo, C. M. Londoño-Parra
Transformers are essential devices in power and distribution systems, since they reduce energy losses produced in the transmission stage. The magnetic system is the most-important part to its operation because energy conversion process will always be defined and bounded by the electromagnetic characteristics of its ferromagnetic core. This paper proposes an experimental method based on electromagnetic principles to obtain an approximated magnetization curve of an electric transformer, which can be used as a reference to analyze magnetic-system-behavior evolution through time. Moreover, the obtained magnetization curve considers voltage and current harmonic components produced during the test. Therefore, a detailed division of input transformer power is done, assuming the total active power are magnetic losses and the total non-active power corresponds to magnetization power. Obtained results showed the proposed method relevance, after comparing it with a magnetization curve which rejects harmonic content of signals and a magnetization curve released by a ferromagnetic material manufacturer.
{"title":"Experimental Magnetization Curve of a Transformer Considering Harmonic Distortion","authors":"Edwin Herlyt Lopera-Mazo, C. M. Londoño-Parra","doi":"10.1109/PEPQA.2019.8851565","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851565","url":null,"abstract":"Transformers are essential devices in power and distribution systems, since they reduce energy losses produced in the transmission stage. The magnetic system is the most-important part to its operation because energy conversion process will always be defined and bounded by the electromagnetic characteristics of its ferromagnetic core. This paper proposes an experimental method based on electromagnetic principles to obtain an approximated magnetization curve of an electric transformer, which can be used as a reference to analyze magnetic-system-behavior evolution through time. Moreover, the obtained magnetization curve considers voltage and current harmonic components produced during the test. Therefore, a detailed division of input transformer power is done, assuming the total active power are magnetic losses and the total non-active power corresponds to magnetization power. Obtained results showed the proposed method relevance, after comparing it with a magnetization curve which rejects harmonic content of signals and a magnetization curve released by a ferromagnetic material manufacturer.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131627858","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 : 2019-05-30DOI: 10.1109/PEPQA.2019.8851564
A. Parrado-Duque, Rusber Rodríguez-Velásquez, G. Osma-Pinto, G. Ordóñez-Plata
The quantification of the impacts of photovoltaic system (PV) integration in the low voltage (LV) power grid is necessary for the historical evaluation of the electrical network with and without PV penetration. This paper presents the study case of the LV electrical network of a university building (Colombia), which has a 9.1 kW PV system. Specifically, the electrical variables monitored were voltages (V), frequency (f), active power (W), voltage distortion (THDv), and harmonics at the Point of Common Coupling (PCC), to determine impairments according to Std. IEEE 1547-2018. PV systems could change the RMS value of voltage at the PCC, therefore, this variable was analysed. Likewise, the frequency was analysed to corroborate the no affectation of the interconnection of the PV system to the electrical network; it is due to the absence of rotational inertia. The solar irradiation information was measured by a pyranometer and the electrical variables by an smart meter, recording the information every 10 minutes for 32 days. The above is an initial step for a comprehensive evaluation of electrical variables with PV generation and future integration of parameters for the resilience evaluation of the electric network.
{"title":"Integration of Photovoltaic System in Low Voltage Electrical Network of the Electrical Engineering Building","authors":"A. Parrado-Duque, Rusber Rodríguez-Velásquez, G. Osma-Pinto, G. Ordóñez-Plata","doi":"10.1109/PEPQA.2019.8851564","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851564","url":null,"abstract":"The quantification of the impacts of photovoltaic system (PV) integration in the low voltage (LV) power grid is necessary for the historical evaluation of the electrical network with and without PV penetration. This paper presents the study case of the LV electrical network of a university building (Colombia), which has a 9.1 kW PV system. Specifically, the electrical variables monitored were voltages (V), frequency (f), active power (W), voltage distortion (THDv), and harmonics at the Point of Common Coupling (PCC), to determine impairments according to Std. IEEE 1547-2018. PV systems could change the RMS value of voltage at the PCC, therefore, this variable was analysed. Likewise, the frequency was analysed to corroborate the no affectation of the interconnection of the PV system to the electrical network; it is due to the absence of rotational inertia. The solar irradiation information was measured by a pyranometer and the electrical variables by an smart meter, recording the information every 10 minutes for 32 days. The above is an initial step for a comprehensive evaluation of electrical variables with PV generation and future integration of parameters for the resilience evaluation of the electric network.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125239090","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 : 2019-05-30DOI: 10.1109/PEPQA.2019.8851566
Diego Gerardo Bernal Coblaeda, Miguel Vivert, Rafael Díez Medina, F. Ruiz, D. Patiño, G. Perilla
A cascade multilevel inverter is simulated and implemented to supply power to the grid from a set of 4 isolated batteries. The phase-shifted carrier PWM modulation strategy is employed in this article, increasing the frequency of the output current. A PI controller is applied to achieve a connection to the grid. Simulation results supplying current on phase, leading and lagging are shown, and experimental results validate the prototype built.
{"title":"A current controller for a grid-tied, cascade multilevel inverter","authors":"Diego Gerardo Bernal Coblaeda, Miguel Vivert, Rafael Díez Medina, F. Ruiz, D. Patiño, G. Perilla","doi":"10.1109/PEPQA.2019.8851566","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851566","url":null,"abstract":"A cascade multilevel inverter is simulated and implemented to supply power to the grid from a set of 4 isolated batteries. The phase-shifted carrier PWM modulation strategy is employed in this article, increasing the frequency of the output current. A PI controller is applied to achieve a connection to the grid. Simulation results supplying current on phase, leading and lagging are shown, and experimental results validate the prototype built.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116021758","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 : 2019-05-01DOI: 10.1109/PEPQA.2019.8851572
H. Espitia, Iván Machón-González, Hilario López-García
This paper shows the optimization of a PD (Proportional Derivative) fuzzy-type Takagi-Sugeno controller, which is used to control the voltage of a single-phase DC-AC inverter. This approach seeks to establish an initial configuration of the fuzzy system which is used as a starting point for the optimization process and thus improve the controller performance. The fuzzy system is designed aiming to have a low number of parameters to be optimized. The results show that the initial proposed configuration allows the successful optimization of the fuzzy controller.
{"title":"Optimization of a Takagi-Sugeno fuzzy controller for voltage regulation of a DC-AC single-phase inverter","authors":"H. Espitia, Iván Machón-González, Hilario López-García","doi":"10.1109/PEPQA.2019.8851572","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851572","url":null,"abstract":"This paper shows the optimization of a PD (Proportional Derivative) fuzzy-type Takagi-Sugeno controller, which is used to control the voltage of a single-phase DC-AC inverter. This approach seeks to establish an initial configuration of the fuzzy system which is used as a starting point for the optimization process and thus improve the controller performance. The fuzzy system is designed aiming to have a low number of parameters to be optimized. The results show that the initial proposed configuration allows the successful optimization of the fuzzy controller.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115285782","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 : 2019-05-01DOI: 10.1109/PEPQA.2019.8851530
María Victoria Gasca, A. Garcés, M. Molinas
The proportional-resonant control (PR-control) is a simple and efficient control, which has the ability to eliminate error in linear time varying signals. This type of control is typically used in applications such as the integration of solar panels, energy storage and electric vehicles among others. Despite having non-linear dynamics, the analysis of the PR-control is usually performed using linear systems theory. This paper proposes a non-linear stability analysis based on Lyapunov theory which formalizes the main stability results on these controls that are standard in industrial applications. The proposed approach is general and independent of the structure of the phase-locked loop which is considered as a vanishing perturbation. This approach allows a better understanding of the control from a non-linear perspective. In addition, it gives an exact criteria for tuning the parameters of the controller. Numerical simulation results in a wide range of scenarios complement the analysis and validate them.
{"title":"Stability Analysis of the Proportional-Resonant Controller in Single Phase Converters","authors":"María Victoria Gasca, A. Garcés, M. Molinas","doi":"10.1109/PEPQA.2019.8851530","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851530","url":null,"abstract":"The proportional-resonant control (PR-control) is a simple and efficient control, which has the ability to eliminate error in linear time varying signals. This type of control is typically used in applications such as the integration of solar panels, energy storage and electric vehicles among others. Despite having non-linear dynamics, the analysis of the PR-control is usually performed using linear systems theory. This paper proposes a non-linear stability analysis based on Lyapunov theory which formalizes the main stability results on these controls that are standard in industrial applications. The proposed approach is general and independent of the structure of the phase-locked loop which is considered as a vanishing perturbation. This approach allows a better understanding of the control from a non-linear perspective. In addition, it gives an exact criteria for tuning the parameters of the controller. Numerical simulation results in a wide range of scenarios complement the analysis and validate them.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123940709","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 : 2019-05-01DOI: 10.1109/PEPQA.2019.8851575
D. Alvarez, Laura S. Rosero, S. Rivera, A. Romero
This document addresses a conceptual model for life cycle asset management of electrical systems within the framework of ISO 55000 standard. The objective is to assess physical electrical assets in short, medium and long term. Hence, a contingencies analysis in real-time is proposed for short term assessment. For medium term, the aim is to estimate the health condition and the criticality for ranking the assets maintenance by the risk index. Finally, in long term, the proposal seeks to estimate both the remaining life and the performance index for critical assets, in order to prioritize their replacement. With these indexes and with the help of risk and opportunity matrices, it is expected to optimize the operation, maintenance and investment plans of the assets, ensuring a balance between the performance of the assets, their risk and the associated costs.
{"title":"A Framework For Asset Management in Electrical Systems, Part I: Conceptual Model","authors":"D. Alvarez, Laura S. Rosero, S. Rivera, A. Romero","doi":"10.1109/PEPQA.2019.8851575","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851575","url":null,"abstract":"This document addresses a conceptual model for life cycle asset management of electrical systems within the framework of ISO 55000 standard. The objective is to assess physical electrical assets in short, medium and long term. Hence, a contingencies analysis in real-time is proposed for short term assessment. For medium term, the aim is to estimate the health condition and the criticality for ranking the assets maintenance by the risk index. Finally, in long term, the proposal seeks to estimate both the remaining life and the performance index for critical assets, in order to prioritize their replacement. With these indexes and with the help of risk and opportunity matrices, it is expected to optimize the operation, maintenance and investment plans of the assets, ensuring a balance between the performance of the assets, their risk and the associated costs.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132613210","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 : 2019-05-01DOI: 10.1109/PEPQA.2019.8851549
Mateo Mancera-Rodríguez, A. Pavas, R. Rincon
This paper considers the polynomial and exponential load models, for the analysis of the parameters behavior, in steady-state perform. The model was made in an electric reference system, in this case 3-Bus system and IEEE 14-Bus system. The development of the analysis is performed to find the cause of the movement, in the load characteristic curve, in order to find the margin of voltage stability. Additionally, this paper considers the limits in voltage established for the country in terms of power quality, to determine the margins of voltage stability and margins of voltage restrictions for a specific load.
{"title":"Load Models for Long-Term Voltage Stability Assessment","authors":"Mateo Mancera-Rodríguez, A. Pavas, R. Rincon","doi":"10.1109/PEPQA.2019.8851549","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851549","url":null,"abstract":"This paper considers the polynomial and exponential load models, for the analysis of the parameters behavior, in steady-state perform. The model was made in an electric reference system, in this case 3-Bus system and IEEE 14-Bus system. The development of the analysis is performed to find the cause of the movement, in the load characteristic curve, in order to find the margin of voltage stability. Additionally, this paper considers the limits in voltage established for the country in terms of power quality, to determine the margins of voltage stability and margins of voltage restrictions for a specific load.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127802468","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 : 2019-05-01DOI: 10.1109/PEPQA.2019.8851554
Alejandra Martínez-Peñaloza, Luisa Carrillo-Sandoval, G. Osma-Pinto
The proliferation of low-power consumption equipment based on power electronics, such as LED and fluorescent lightings, has caused changes in the waveform of voltage and current signals in electrical networks. For this reason, several studies approach the modeling of these lighting loads to analyze their impact on the harmonic distortion in low-voltage networks. Currently, the massive penetration of LED lighting in replacement of fluorescent technology is evident; however, fluorescent lighting remains as a representative load in the energy consumption of buildings. Therefore, this paper presents the modeling of both types of lighting loads from two Norton equivalent models, the coupled matrix model and the decoupled matrix model, used to estimate the distortion of the current signal, the power consumption of the luminaires, and an escalation analysis of the models. In addition, 10 specific voltage signals were used to validate these models, thus presenting active power errors, NRMSE estimation percentages, and an escalation analysis of the models from the THDi indices.
{"title":"Determination and Performance Analysis of the Norton Equivalent Models for Fluorescents and LED Recessed Lightings","authors":"Alejandra Martínez-Peñaloza, Luisa Carrillo-Sandoval, G. Osma-Pinto","doi":"10.1109/PEPQA.2019.8851554","DOIUrl":"https://doi.org/10.1109/PEPQA.2019.8851554","url":null,"abstract":"The proliferation of low-power consumption equipment based on power electronics, such as LED and fluorescent lightings, has caused changes in the waveform of voltage and current signals in electrical networks. For this reason, several studies approach the modeling of these lighting loads to analyze their impact on the harmonic distortion in low-voltage networks. Currently, the massive penetration of LED lighting in replacement of fluorescent technology is evident; however, fluorescent lighting remains as a representative load in the energy consumption of buildings. Therefore, this paper presents the modeling of both types of lighting loads from two Norton equivalent models, the coupled matrix model and the decoupled matrix model, used to estimate the distortion of the current signal, the power consumption of the luminaires, and an escalation analysis of the models. In addition, 10 specific voltage signals were used to validate these models, thus presenting active power errors, NRMSE estimation percentages, and an escalation analysis of the models from the THDi indices.","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124317438","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 : 2019-05-01DOI: 10.1109/pepqa.2019.8851556
{"title":"PEPQA 2019 Authors Index","authors":"","doi":"10.1109/pepqa.2019.8851556","DOIUrl":"https://doi.org/10.1109/pepqa.2019.8851556","url":null,"abstract":"","PeriodicalId":192905,"journal":{"name":"2019 IEEE Workshop on Power Electronics and Power Quality Applications (PEPQA)","volume":"514 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123061418","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：