Pub Date : 2013-06-13DOI: 10.1109/ICPEC.2013.6527616
S. Ramya, A. Napolean, T. Manoharan
The objective of this paper is to propose a multi-input power converter for the hybrid system that interfaces two unidirectional ports for input power sources, a bidirectional port for a storage element, and a port for output load in a unified structure. The two input ports for simultaneously converting two different input power sources with low voltages to a stable output power with a high voltage. According to various situations, the operational states of the proposed converter can be divided into three states based on battery utilization. In order to ensure that the system operates with high efficiency, this paper proposes a power management control scheme, which controls the bidirectional converter operating under boost mode according to the operation condition of the PV/Wind, so that the battery can be charged or discharged. The integration of the hybrid renewable power system is implemented and simulated using MATLAB/SIMULINK.
{"title":"A novel converter topology for stand-alone hybrid PV/Wind/battery power system using Matlab/Simulink","authors":"S. Ramya, A. Napolean, T. Manoharan","doi":"10.1109/ICPEC.2013.6527616","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527616","url":null,"abstract":"The objective of this paper is to propose a multi-input power converter for the hybrid system that interfaces two unidirectional ports for input power sources, a bidirectional port for a storage element, and a port for output load in a unified structure. The two input ports for simultaneously converting two different input power sources with low voltages to a stable output power with a high voltage. According to various situations, the operational states of the proposed converter can be divided into three states based on battery utilization. In order to ensure that the system operates with high efficiency, this paper proposes a power management control scheme, which controls the bidirectional converter operating under boost mode according to the operation condition of the PV/Wind, so that the battery can be charged or discharged. The integration of the hybrid renewable power system is implemented and simulated using MATLAB/SIMULINK.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"152 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132227899","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527742
S. Lakshmi, Noby George, U. S., Kothari D
A multilevel inverter is a power electronic device that is used for high voltage and high power applications and has many advantages like, low switching stress, low total harmonic distortion (THD). Hence, the size and bulkiness of passive filters can be reduced. This paper proposes two new topologies of a 7-level cascaded multilevel inverter with reduced number of switches than that of conventional type which has 12 switches. The topologies consist of circuits with 9 switches and 7 switches for the same 7-level output. Therefore with less number of switches, there will be a reduction in gate drive circuitry and also very few switches will be conducting for specific intervals of time. The SPWM technique is implemented using multicarrier wave signals. Level Shifted triangular waves are used in comparison with sinusoidal reference to generate Sine PWM switching sequence. The number of level shifted triangular waves depends on the number of levels in the output. i.e. for n levels, n-1 number of carrier waves. This paper uses 1 KHz SPWM pulses with a modulation index of 0.8. The circuits are simulated using SPWM technique and the effect of the harmonic spectrum is analyzed. A comparison is made for the topologies with 9 switches and 7 switches and an effective reduction in THD has been observed for the circuits with less number of switches. The THD for 9 switches is 14% and the THD for 7 switches is 12.5%. The circuits are modeled and simulated with the help of MATLAB/SIMULINK.
{"title":"Cascaded seven level inverter with reduced number of switches using level shifting PWM technique","authors":"S. Lakshmi, Noby George, U. S., Kothari D","doi":"10.1109/ICPEC.2013.6527742","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527742","url":null,"abstract":"A multilevel inverter is a power electronic device that is used for high voltage and high power applications and has many advantages like, low switching stress, low total harmonic distortion (THD). Hence, the size and bulkiness of passive filters can be reduced. This paper proposes two new topologies of a 7-level cascaded multilevel inverter with reduced number of switches than that of conventional type which has 12 switches. The topologies consist of circuits with 9 switches and 7 switches for the same 7-level output. Therefore with less number of switches, there will be a reduction in gate drive circuitry and also very few switches will be conducting for specific intervals of time. The SPWM technique is implemented using multicarrier wave signals. Level Shifted triangular waves are used in comparison with sinusoidal reference to generate Sine PWM switching sequence. The number of level shifted triangular waves depends on the number of levels in the output. i.e. for n levels, n-1 number of carrier waves. This paper uses 1 KHz SPWM pulses with a modulation index of 0.8. The circuits are simulated using SPWM technique and the effect of the harmonic spectrum is analyzed. A comparison is made for the topologies with 9 switches and 7 switches and an effective reduction in THD has been observed for the circuits with less number of switches. The THD for 9 switches is 14% and the THD for 7 switches is 12.5%. The circuits are modeled and simulated with the help of MATLAB/SIMULINK.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"90 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114023121","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527625
G. Raman, Dr. Suvanam Sasidhar Babu, P. S. Venkataramu, M. Nagaraja
In this paper, sensitivity analysis of transmission line is carried out by using line outage of transmission line. For each of the line outage highly sensitive line is identified and Static Var Compensator and Thyristor Controlled Series Capacitors are individually connected in this line and the system improvement as indicated by voltage profiles are illustrated. The study is carried out on IEEE 14 bus system using Mi-Power software.
{"title":"Sensitivity factor based improvement studies incorporating facts devices under line outage contingency","authors":"G. Raman, Dr. Suvanam Sasidhar Babu, P. S. Venkataramu, M. Nagaraja","doi":"10.1109/ICPEC.2013.6527625","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527625","url":null,"abstract":"In this paper, sensitivity analysis of transmission line is carried out by using line outage of transmission line. For each of the line outage highly sensitive line is identified and Static Var Compensator and Thyristor Controlled Series Capacitors are individually connected in this line and the system improvement as indicated by voltage profiles are illustrated. The study is carried out on IEEE 14 bus system using Mi-Power software.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123515449","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527721
N. Mohammad, Anomadarshi Barua, M. A. Arafat
Power utilities in different countries especially in the developing ones are incurring huge losses due to electricity theft. This paper proposes a prepaid energy metering system to control electricity theft. In this system a smart energy meter is installed in every consumer unit and a server is maintained at the service provider side. Both the meter and the server are equipped with GSM module which facilitates bidirectional communication between the two ends using the existing GSM infrastructure. Consumers can easily recharge their energy meter by sending a PIN number hidden in a scratch card to the server using SMS. This paper presents some measures to control meter bypassing and tampering. The bidirectional GSM communication using SMS ensures the effectiveness of these measures. Pilferage of electricity can be substantially reduced by incorporating the proposed measures along with the prepaid metering scheme. Legal actions against dishonest consumers can also be taken in this system.
{"title":"A smart prepaid energy metering system to control electricity theft","authors":"N. Mohammad, Anomadarshi Barua, M. A. Arafat","doi":"10.1109/ICPEC.2013.6527721","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527721","url":null,"abstract":"Power utilities in different countries especially in the developing ones are incurring huge losses due to electricity theft. This paper proposes a prepaid energy metering system to control electricity theft. In this system a smart energy meter is installed in every consumer unit and a server is maintained at the service provider side. Both the meter and the server are equipped with GSM module which facilitates bidirectional communication between the two ends using the existing GSM infrastructure. Consumers can easily recharge their energy meter by sending a PIN number hidden in a scratch card to the server using SMS. This paper presents some measures to control meter bypassing and tampering. The bidirectional GSM communication using SMS ensures the effectiveness of these measures. Pilferage of electricity can be substantially reduced by incorporating the proposed measures along with the prepaid metering scheme. Legal actions against dishonest consumers can also be taken in this system.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125136724","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527646
A. R. Shete, A. Thorat
Now a day's Low Tension (L.T.) & High Tension (H.T.) capacitors are manufactured by using All Polypropylene Film (APP) and L.T. capacitors. All Polypropylene Film has very less dielectric losses, long life, high voltage stress. So it is widely used in H.T. as well as L.T. capacitor. However, the cost of L.T. capacitor is increased due to use of APP in L.T. capacitor. As more costing, the use of APP in L.T. capacitor is limited. The main disadvantage of APP is non-self-healing property. On the other hand, Metallized Polypropylene Film has self-healing property. There are many advantages due to use of MPP film in capacitor - the size of capacitor is reduced, losses are less and cost of capacitor is decreased. So, it is an optimal technique to use MPP in manufacturing of H. T. capacitors.
{"title":"An optimal technique for manufacturing of H.T. capacitor by using Metallized Polypropylene Film","authors":"A. R. Shete, A. Thorat","doi":"10.1109/ICPEC.2013.6527646","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527646","url":null,"abstract":"Now a day's Low Tension (L.T.) & High Tension (H.T.) capacitors are manufactured by using All Polypropylene Film (APP) and L.T. capacitors. All Polypropylene Film has very less dielectric losses, long life, high voltage stress. So it is widely used in H.T. as well as L.T. capacitor. However, the cost of L.T. capacitor is increased due to use of APP in L.T. capacitor. As more costing, the use of APP in L.T. capacitor is limited. The main disadvantage of APP is non-self-healing property. On the other hand, Metallized Polypropylene Film has self-healing property. There are many advantages due to use of MPP film in capacitor - the size of capacitor is reduced, losses are less and cost of capacitor is decreased. So, it is an optimal technique to use MPP in manufacturing of H. T. capacitors.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127896989","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527636
S. R. Gaigowal, M. Renge
Day by day energy consumption is increasing. It is an urgent need to increase power generation and hence increase in power transmission capability. There is an increasing demand of power flow control in power systems of the future and FACTS devices are the most suitable devices to control power flow. However cost and reliability are the main issues that create hurdles in widespread application of FACTS Devices. Distributed-series FACTS Controller gives an opportunity to realize cost effective power flow control. In this Paper some studies are presented on Distributed series FACTS controller to control active power flow. Multilevel Inverter topologies are studied for Distributed FACTS Controller.
{"title":"Some studies of distributed series FACTS controller to control active power flow through transmission line","authors":"S. R. Gaigowal, M. Renge","doi":"10.1109/ICPEC.2013.6527636","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527636","url":null,"abstract":"Day by day energy consumption is increasing. It is an urgent need to increase power generation and hence increase in power transmission capability. There is an increasing demand of power flow control in power systems of the future and FACTS devices are the most suitable devices to control power flow. However cost and reliability are the main issues that create hurdles in widespread application of FACTS Devices. Distributed-series FACTS Controller gives an opportunity to realize cost effective power flow control. In this Paper some studies are presented on Distributed series FACTS controller to control active power flow. Multilevel Inverter topologies are studied for Distributed FACTS Controller.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121226695","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527709
R. Hariharan
The smart meter module is designed and implemented in LABVIEW environment. Whenever there is mismatch in power generation and demand, it causes the power shutdown and low voltage problems. Due to this the life of the various gadgets connected to the power system gets reduced. These drawbacks can be regulated by the smart meter module. Using smart meters at home, priority scheduling of the load can be carried out during peak load periods when the demand is greater than the supply. In this way, even when there is power shortage, all the houses connected to a network or grid will be supplied with power to run the minimum essential loads, while the less priority loads will be switched off automatically. This control provides an appealing solution to the existing power shortage. This module is created by the LabVIEW environment.
{"title":"Design of controlling the smart meter to equalize the power and demand based on virtual instrumentation","authors":"R. Hariharan","doi":"10.1109/ICPEC.2013.6527709","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527709","url":null,"abstract":"The smart meter module is designed and implemented in LABVIEW environment. Whenever there is mismatch in power generation and demand, it causes the power shutdown and low voltage problems. Due to this the life of the various gadgets connected to the power system gets reduced. These drawbacks can be regulated by the smart meter module. Using smart meters at home, priority scheduling of the load can be carried out during peak load periods when the demand is greater than the supply. In this way, even when there is power shortage, all the houses connected to a network or grid will be supplied with power to run the minimum essential loads, while the less priority loads will be switched off automatically. This control provides an appealing solution to the existing power shortage. This module is created by the LabVIEW environment.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115967535","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527631
K. Balamurugan, G. Suganya, N. Manojkumar
Nowadays, the power transmission network is expanding and is getting more complicated day by day. The problems of uncontrolled loop flows, overloading, excess of short circuit current levels and system instabilities are causes of concern for a power engineer. These serious problems have necessitated new transmission technologies to be adopted such as FACTS (Flexible AC Transmission System) devices which make electrical energy transmission more efficient and reliable. Among the FACTS controllers the TCSC (Thyristor Controlled Series Compensators) plays a major role. TCSC is mainly used to enhance line loadability and damp inter-area oscillations for smooth synchronous operation of the interconnected regions. Thus TCSC is used to enhance the effective performance of the system. The main objective of this paper is to examine the improvement of power system stability by introducing TCSC in the power system model through the inspection of their waveforms, where the design and simulation is done by using PSCAD (Power System Computer Aided Design).
{"title":"Improving power system dynamics by series connected FACTS controllers (TCSC)","authors":"K. Balamurugan, G. Suganya, N. Manojkumar","doi":"10.1109/ICPEC.2013.6527631","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527631","url":null,"abstract":"Nowadays, the power transmission network is expanding and is getting more complicated day by day. The problems of uncontrolled loop flows, overloading, excess of short circuit current levels and system instabilities are causes of concern for a power engineer. These serious problems have necessitated new transmission technologies to be adopted such as FACTS (Flexible AC Transmission System) devices which make electrical energy transmission more efficient and reliable. Among the FACTS controllers the TCSC (Thyristor Controlled Series Compensators) plays a major role. TCSC is mainly used to enhance line loadability and damp inter-area oscillations for smooth synchronous operation of the interconnected regions. Thus TCSC is used to enhance the effective performance of the system. The main objective of this paper is to examine the improvement of power system stability by introducing TCSC in the power system model through the inspection of their waveforms, where the design and simulation is done by using PSCAD (Power System Computer Aided Design).","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129477258","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527618
A. Kane, V. Verma
The objective of this paper is to develop mathematical model of Photovoltaic (PV) module and study effects of environmental factors on its performance. Output of PV module strongly depends on environmental conditions like solar irradiance, ambient temperature and wind speed etc. Mathematical model is developed in Matlab/Simulink environment by considering effect of above conditions. Maximum power point voltage and PV module temperature relationship is determined utilizing simulated results. An attempt has been done to develop Maximum power point tracking (MPPT) algorithm based on cell temperature and solar irradiance to improve the efficiency of PV power generation system.
{"title":"Characterization of PV cell-environmental factors consideration","authors":"A. Kane, V. Verma","doi":"10.1109/ICPEC.2013.6527618","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527618","url":null,"abstract":"The objective of this paper is to develop mathematical model of Photovoltaic (PV) module and study effects of environmental factors on its performance. Output of PV module strongly depends on environmental conditions like solar irradiance, ambient temperature and wind speed etc. Mathematical model is developed in Matlab/Simulink environment by considering effect of above conditions. Maximum power point voltage and PV module temperature relationship is determined utilizing simulated results. An attempt has been done to develop Maximum power point tracking (MPPT) algorithm based on cell temperature and solar irradiance to improve the efficiency of PV power generation system.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"28 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129704423","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 : 2013-06-13DOI: 10.1109/ICPEC.2013.6527620
K. Sudhakar, N. Jain, S. Bagga
In this paper, an attempt is made to evaluate the effect of colors of light on the performance of solar photovoltaic module. A case study is conducted to experimentally verify the effect of various color filters on the performance of Solar panel at Energy Centre, MANIT, Bhopal, India. Based on the temperature of the cell, solar irradiance and photonic theory, the efficiency and power output of the PV system have been evaluated. An analytical model based on physical parameters is also developed to evaluate the efficiency of solar panel. The results show that the present day PV technology is influenced by the red color of light. In other words, visible portion of the solar spectrum influences the performance of the solar panel then the infra red light.
{"title":"Effect of color filter on the performance of solar photovoltaic module","authors":"K. Sudhakar, N. Jain, S. Bagga","doi":"10.1109/ICPEC.2013.6527620","DOIUrl":"https://doi.org/10.1109/ICPEC.2013.6527620","url":null,"abstract":"In this paper, an attempt is made to evaluate the effect of colors of light on the performance of solar photovoltaic module. A case study is conducted to experimentally verify the effect of various color filters on the performance of Solar panel at Energy Centre, MANIT, Bhopal, India. Based on the temperature of the cell, solar irradiance and photonic theory, the efficiency and power output of the PV system have been evaluated. An analytical model based on physical parameters is also developed to evaluate the efficiency of solar panel. The results show that the present day PV technology is influenced by the red color of light. In other words, visible portion of the solar spectrum influences the performance of the solar panel then the infra red light.","PeriodicalId":176900,"journal":{"name":"2013 International Conference on Power, Energy and Control (ICPEC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130280027","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：