Pub Date : 2009-12-11DOI: 10.1109/INTLEC.2009.5351815
P. Wipasuramonton, Kowit Sowsuwan
A current-controlled PWM technique for brushless DC drives with only a single current sensor, particularly a low-cost shunt resistor, is presented. On one hand, the PWM technique offers a unipolar modulation which does not produce current in the floating phase. Therefore the winding currents can be sensed directly with the shunt resistor. On the other hand, the current is controlled with a predictive current control algorithm, which gives fast response and is so simple that it can be executed in every period of the PWM interrupt. In addition, the unipolar PWM modulation features low switching and winding losses. Since the standard three-phase bridge power inverter, without any modification, is maintained, the scheme is therefore suitable for household appliances and HVAC applications in which high robustness, high reliability, and low cost are mainly required.
{"title":"Current-controlled PWM Technique for brushless DC motor drives with a single current sensing resistor","authors":"P. Wipasuramonton, Kowit Sowsuwan","doi":"10.1109/INTLEC.2009.5351815","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351815","url":null,"abstract":"A current-controlled PWM technique for brushless DC drives with only a single current sensor, particularly a low-cost shunt resistor, is presented. On one hand, the PWM technique offers a unipolar modulation which does not produce current in the floating phase. Therefore the winding currents can be sensed directly with the shunt resistor. On the other hand, the current is controlled with a predictive current control algorithm, which gives fast response and is so simple that it can be executed in every period of the PWM interrupt. In addition, the unipolar PWM modulation features low switching and winding losses. Since the standard three-phase bridge power inverter, without any modification, is maintained, the scheme is therefore suitable for household appliances and HVAC applications in which high robustness, high reliability, and low cost are mainly required.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125695364","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5351794
Chang-Ki Kim, Jiseong Park, S. Hahn, Sang-Yong Jung
The iron loss characteristics of high powered Interior buried Permanent Magnet Synchronous Motor (IPMSM) having open slot structure has been numerically investigated in terms of space harmonics. In particular, cross-magnetization of highly saturated IPMSM has been identified using the synthetic flux linkages. In addition, numerical investigation on the space harmonics of EMF waveform and iron loss in IPMSM has been carried out. Furthermore, optimal sizing of segmented PM and cavities in rotor of 280kW IPMSM with fractional number slots are given to reduce space harmonics and iron loss at the same time.
{"title":"Numerical investigation on iron loss in the high powered Interior buried PM Synchronous machine considering harmonic EMF waveform","authors":"Chang-Ki Kim, Jiseong Park, S. Hahn, Sang-Yong Jung","doi":"10.1109/INTLEC.2009.5351794","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351794","url":null,"abstract":"The iron loss characteristics of high powered Interior buried Permanent Magnet Synchronous Motor (IPMSM) having open slot structure has been numerically investigated in terms of space harmonics. In particular, cross-magnetization of highly saturated IPMSM has been identified using the synthetic flux linkages. In addition, numerical investigation on the space harmonics of EMF waveform and iron loss in IPMSM has been carried out. Furthermore, optimal sizing of segmented PM and cavities in rotor of 280kW IPMSM with fractional number slots are given to reduce space harmonics and iron loss at the same time.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131101128","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5351911
Jinbin Zhao
A novel non-isolation soft-switching buck converter for high step-down conversion is proposed in this paper. Compared with buck converter and tapped-inductor converter, it can easily extend the duty cycle, achieves lower output voltage and soft-switching operation by adding a series inductor and a clamp capacitor. To demonstrate the results, principle of operation is described and detailed steady-state analysis is presented. Finally, a 48V/1V, 10A prototype converter is built to verify the theoretical analysis and shows the significant advantages.
{"title":"Non-isolation soft-switching buck converter for high-step-down conversion","authors":"Jinbin Zhao","doi":"10.1109/INTLEC.2009.5351911","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351911","url":null,"abstract":"A novel non-isolation soft-switching buck converter for high step-down conversion is proposed in this paper. Compared with buck converter and tapped-inductor converter, it can easily extend the duty cycle, achieves lower output voltage and soft-switching operation by adding a series inductor and a clamp capacitor. To demonstrate the results, principle of operation is described and detailed steady-state analysis is presented. Finally, a 48V/1V, 10A prototype converter is built to verify the theoretical analysis and shows the significant advantages.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128026942","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5352083
L. E. Menzhi, A. Saad
In this paper, a new method for induction motor fault diagnosis is presented. It is based on the so-called voltage spectrum of an auxiliary winding which is a small coil inserted between two of the stator phases. An expression of the inserted winding voltage and its Park components are presented. After that, discrete Fourier transform analyzer is required for converting the voltage signals from the time domain to the frequency domain. Simulations results curried out in the case of an oscillating, varying load torque and non defected motor show the effectiveness of the proposed method.
{"title":"Induction motor diagnosis using voltage spectrum of an auxiliary winding - time varying load torque","authors":"L. E. Menzhi, A. Saad","doi":"10.1109/INTLEC.2009.5352083","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5352083","url":null,"abstract":"In this paper, a new method for induction motor fault diagnosis is presented. It is based on the so-called voltage spectrum of an auxiliary winding which is a small coil inserted between two of the stator phases. An expression of the inserted winding voltage and its Park components are presented. After that, discrete Fourier transform analyzer is required for converting the voltage signals from the time domain to the frequency domain. Simulations results curried out in the case of an oscillating, varying load torque and non defected motor show the effectiveness of the proposed method.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133093246","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5351853
Tadahiko Sato, H. Matsuo, H. Ota, Y. Ishizuka, N. Higashi
This paper deals with an improvement of a power efficiency of a multi-oscillated current resonant type DC-DC converter. The current resonant type converter employs generally the pulse frequency modulation and its magnetizing inductance is set relatively low. For this reason, the magnetizing current through the converter causes a power loss under a light load. In order to solve this problem, a multi-oscillated current resonant type DC-DC converter has been proposed, and revealed the advantage of its control method which can reduce power loss under light load and keep low switching noise. In this topology, output power is controlled by duty ratio and operating frequency is determined by resonant condition. In this paper, an analysis of power loss by focusing on switching devices in this converter to improve power efficiency was given. As a result, it was confirmed that the loss of diodes in secondary side occupies main loss. Adopting the synchronous rectifier in the secondary side, the maximum power efficiency is improved to 96.3%, and the average efficiency, which is averaged efficiency at 25%, 50%, 75% and 100% of the rated load, reached 95.5%.
{"title":"Power efficiency improvement of a multi-oscillated current resonant type DC-DC converter","authors":"Tadahiko Sato, H. Matsuo, H. Ota, Y. Ishizuka, N. Higashi","doi":"10.1109/INTLEC.2009.5351853","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351853","url":null,"abstract":"This paper deals with an improvement of a power efficiency of a multi-oscillated current resonant type DC-DC converter. The current resonant type converter employs generally the pulse frequency modulation and its magnetizing inductance is set relatively low. For this reason, the magnetizing current through the converter causes a power loss under a light load. In order to solve this problem, a multi-oscillated current resonant type DC-DC converter has been proposed, and revealed the advantage of its control method which can reduce power loss under light load and keep low switching noise. In this topology, output power is controlled by duty ratio and operating frequency is determined by resonant condition. In this paper, an analysis of power loss by focusing on switching devices in this converter to improve power efficiency was given. As a result, it was confirmed that the loss of diodes in secondary side occupies main loss. Adopting the synchronous rectifier in the secondary side, the maximum power efficiency is improved to 96.3%, and the average efficiency, which is averaged efficiency at 25%, 50%, 75% and 100% of the rated load, reached 95.5%.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133219589","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5352040
K. Fukushima, I. Norigoe, M. Shoyama, T. Ninomiya, Y. Harada, K. Tsukakoshi
This paper examines the effect of input current-ripple reduction on Pulse-link DC-AC converter for fuel cells applications. For reducing the input current-ripple, series LC circuit has been connected in parallel at the Pulse-link DC-AC converter. The input current-ripple characteristics have two main domains with combination of series LC parameters. The current-ripple level depends on inductance values. Input current-ripple is reduced when the inductor current flown at series LC circuit has zero-slopes in one switching period. At that time, small parameters values can be reached.
{"title":"The effect of series LC circuit parameters on current-ripple reduction in Pulse-link DC-AC converter for fuel cell applications","authors":"K. Fukushima, I. Norigoe, M. Shoyama, T. Ninomiya, Y. Harada, K. Tsukakoshi","doi":"10.1109/INTLEC.2009.5352040","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5352040","url":null,"abstract":"This paper examines the effect of input current-ripple reduction on Pulse-link DC-AC converter for fuel cells applications. For reducing the input current-ripple, series LC circuit has been connected in parallel at the Pulse-link DC-AC converter. The input current-ripple characteristics have two main domains with combination of series LC parameters. The current-ripple level depends on inductance values. Input current-ripple is reduced when the inductor current flown at series LC circuit has zero-slopes in one switching period. At that time, small parameters values can be reached.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131919260","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5351932
Bong-Joo Choi, Y. Oh, K. Ahn, Heejun Kim
This paper reviewed the development of a 3-phase 125kW grid connected PV inverter and changes in the conversion performance of the inverter based on the gain of the low frequency isolation transformer for isolation between solar and the grid. The 125kW PV inverter consists of a transformer with the grid frequency for isolation between input and output (galvanic isolation) and it has the output power of 60Hz, 3P 3W 380Vac. P&O technique was used for MPPT (Maximum Power Point Tracking) and Active Phase Shift technique was used through changes in reactive power to prevent a islanding operation. Inverter control was achieved based on 16-bit DSP. This paper discussed about the conversion performance of the 125kW inverter in relation to the system and the result of development of THD, MPPT etc and mentioned about the result of comparison of the conversion performance of the inverter based on the efficiency of the low frequency transformer.
{"title":"Development of 125kW grid-tied PV inverter and research on efficiency vs. transformer turn ratio","authors":"Bong-Joo Choi, Y. Oh, K. Ahn, Heejun Kim","doi":"10.1109/INTLEC.2009.5351932","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351932","url":null,"abstract":"This paper reviewed the development of a 3-phase 125kW grid connected PV inverter and changes in the conversion performance of the inverter based on the gain of the low frequency isolation transformer for isolation between solar and the grid. The 125kW PV inverter consists of a transformer with the grid frequency for isolation between input and output (galvanic isolation) and it has the output power of 60Hz, 3P 3W 380Vac. P&O technique was used for MPPT (Maximum Power Point Tracking) and Active Phase Shift technique was used through changes in reactive power to prevent a islanding operation. Inverter control was achieved based on 16-bit DSP. This paper discussed about the conversion performance of the 125kW inverter in relation to the system and the result of development of THD, MPPT etc and mentioned about the result of comparison of the conversion performance of the inverter based on the efficiency of the low frequency transformer.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131993135","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5352052
C. Bianco, F. Cucchietti, G. Griffa, Hong Yu-ping, Kong Xiaoming, Chen Qiao, Luo Shudong, Han Dong
The concept of the energy-saving strategy has become in recent years one of the top priorities of Telecom Operators and Governments. To this end, the deployment of the Next Generation Networks represents one of the main drivers towards the reduction of the energy bill. The NGN architecture can include different scenarios: FTTE, FTTCab, FTTB or FTTH. Among these, the FTTCab certainly brings the greatest challenges concerning the issue of heat dissipation. To this end, the present paper describes the first field trial (jointly carried on by Telecom Italia and Huawei) results for an innovative cooling solution: the Free Cooling Cabinet. This system directly uses the external fresh air in order to increase the cooling efficiency. In particular, data collected from the field trial and concerning internal/external temperature, humidity as well as noise levels will be reported. Finally, the next steps of the trial will be anticipated.
{"title":"An update on the field trial concerning Free Cooling solution for FTTCab architecture","authors":"C. Bianco, F. Cucchietti, G. Griffa, Hong Yu-ping, Kong Xiaoming, Chen Qiao, Luo Shudong, Han Dong","doi":"10.1109/INTLEC.2009.5352052","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5352052","url":null,"abstract":"The concept of the energy-saving strategy has become in recent years one of the top priorities of Telecom Operators and Governments. To this end, the deployment of the Next Generation Networks represents one of the main drivers towards the reduction of the energy bill. The NGN architecture can include different scenarios: FTTE, FTTCab, FTTB or FTTH. Among these, the FTTCab certainly brings the greatest challenges concerning the issue of heat dissipation. To this end, the present paper describes the first field trial (jointly carried on by Telecom Italia and Huawei) results for an innovative cooling solution: the Free Cooling Cabinet. This system directly uses the external fresh air in order to increase the cooling efficiency. In particular, data collected from the field trial and concerning internal/external temperature, humidity as well as noise levels will be reported. Finally, the next steps of the trial will be anticipated.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132218010","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5351817
Junseok Song, A. Kwasinski
A multiple-input converter for photovoltaic-powered communication sites is analyzed. The study shows that the duty cycles of a multiple-input converter, which control the power delivered by each source, may have practical limitations when each photovoltaic module attempts to achieve its own maximum power point at the same time. This paper discusses an alternative circuit that has two coupled inductors in a common output stage, which may enable the multiple-input converter to overcome the limited duty cycles. The relationship between the duty cycles and the power supplied by each input is derived mathematically in order to theoretically analyze the effects given by the limitations. Power budgeting with respect to each source is also demonstrated with simulations.
{"title":"Analysis of the effects of duty cycle constraints in multiple-input converters for photovoltaic applications","authors":"Junseok Song, A. Kwasinski","doi":"10.1109/INTLEC.2009.5351817","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351817","url":null,"abstract":"A multiple-input converter for photovoltaic-powered communication sites is analyzed. The study shows that the duty cycles of a multiple-input converter, which control the power delivered by each source, may have practical limitations when each photovoltaic module attempts to achieve its own maximum power point at the same time. This paper discusses an alternative circuit that has two coupled inductors in a common output stage, which may enable the multiple-input converter to overcome the limited duty cycles. The relationship between the duty cycles and the power supplied by each input is derived mathematically in order to theoretically analyze the effects given by the limitations. Power budgeting with respect to each source is also demonstrated with simulations.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130309629","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 : 2009-12-11DOI: 10.1109/INTLEC.2009.5351982
Hyun-Sik Song, Jin-Beom Jung, Baek-haeng Lee, Dong-hyun Shin, Byounghoon Kim, Yu-Cheol Park, Hoon Heo, Heejun Kim
There have been a number of methods proposed for accurate state of charge (SOC) estimation of a battery as an important role of the battery management System (BMS). However, adequate test data of batteries and BMS development costs must be taken into consideration before application in actual vehicles. In addition, different algorithms need to be adopted according to the type of energy storage device and system configuration. For a mild-HEV hybrid energy storage device that uses the ultracapacitor module and the VRLA battery, the small capacitance of ultracapacitor module makes accurate SOC difficult. Accordingly, this paper introduces a dynamic SOC estimation algorithm capable of SOC compensation of the ultracapacitor module even when there is current input and output. A cycle profile that simulates the operating conditions of a mild-HEV was applied to a vehicle simulator to verify the effectiveness of the proposed algorithm based on testing.
{"title":"A study on the dynamic SOC compensation of an ultracapacitor module for the hybrid energy storage system","authors":"Hyun-Sik Song, Jin-Beom Jung, Baek-haeng Lee, Dong-hyun Shin, Byounghoon Kim, Yu-Cheol Park, Hoon Heo, Heejun Kim","doi":"10.1109/INTLEC.2009.5351982","DOIUrl":"https://doi.org/10.1109/INTLEC.2009.5351982","url":null,"abstract":"There have been a number of methods proposed for accurate state of charge (SOC) estimation of a battery as an important role of the battery management System (BMS). However, adequate test data of batteries and BMS development costs must be taken into consideration before application in actual vehicles. In addition, different algorithms need to be adopted according to the type of energy storage device and system configuration. For a mild-HEV hybrid energy storage device that uses the ultracapacitor module and the VRLA battery, the small capacitance of ultracapacitor module makes accurate SOC difficult. Accordingly, this paper introduces a dynamic SOC estimation algorithm capable of SOC compensation of the ultracapacitor module even when there is current input and output. A cycle profile that simulates the operating conditions of a mild-HEV was applied to a vehicle simulator to verify the effectiveness of the proposed algorithm based on testing.","PeriodicalId":445164,"journal":{"name":"INTELEC 2009 - 31st International Telecommunications Energy Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2009-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115529755","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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