| 61. |
- Zhu, Kun, 1983-, et al.
(författare)
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Design of Robust Wide-Area Damping Controller Based on Synchronized Phasor
- 2012
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Ingår i: The 9th International Conference on Advances in Power System Control, Operation & Management (APSCOM 2012), 18 November-21 November 2012, Kowloon Shangri-La Hotel, Hong Kong: Conference Handbook. - Hongkong : Institution of Engineering and Technology.
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Konferensbidrag (refereegranskat)
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| 62. |
- Zhu, Kun, et al.
(författare)
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Design of wide-area damping systems based on the capabilities of the supporting Information Communication Technology infrastructure
- 2014
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Ingår i: IET Generation, Transmission & Distribution. - : Institution of Engineering and Technology (IET). - 1751-8687 .- 1751-8695. ; 8:4, s. 640-650
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Tidskriftsartikel (refereegranskat)abstract
- The dependence of the functionality of the wide-area monitoring and control (WAMC) systems on the capabilities of their underlying Information Communication Technology (ICT) infrastructure indicates that the parameterisation of the WAMC application algorithm should be coordinated with the design of the supporting ICT system. This study presents a systematic approach to design wide-area damping systems considering phasor measurement unit (PMU) communication delays and data frame losses. The proposed design method is applied to calibrate a wide-area damping system based on generalised predictive control (GPC) for demonstration purposes. In addition, a framework to guide the parameterisation of the GPC- based wide-area damping system is also provided. This research offers a better perspective to predict the capabilities of the underlying ICT infrastructure in the WAMC systems. Moreover, the proposed design method can be generalised to design delay-robust damping systems with compensation limits. Finally, it also offers an opportunity to associate the parameterisation of the damping system with the capabilities of its supporting ICT infrastructure and the reliability of the intended damping control function.
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| 63. |
- Zhu, Kun, 1983-, et al.
(författare)
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Design Requirements of Wide-Area Damping Systems-Using Empirical Data From a Utility IP Network
- 2014
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Ingår i: IEEE Transactions on Smart Grid. - 1949-3053 .- 1949-3061. ; 5:2, s. 829-838
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Tidskriftsartikel (refereegranskat)abstract
- Phasor Measurement Unit (PMU) communication delays and data frame losses play a critical role in designing of wide-area damping systems driven by synchrophasor technology. While there are a plethora of simulation-based studies addressing this issue, empirical results from actual PMUs deployed in the field are rare. This paper provides important insights into the characterization of PMU communication delays and data frame losses based on empirical results collected from a utility IP network. Additionally, efforts are also made to elicit design requirements considering the above PMU data quality problems. Furthermore, three distinct delay-robust wide-area damping control schemes parameterized according to the proposed requirements are validated against the empirical delays and data frame losses. Time-domain simulation results suggest that the control schemes in question can effectively stabilize the power system in all of the tested scenarios.
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| 64. |
- Zhu, Kun, 1983-, et al.
(författare)
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Examination of data delay and packet loss for wide-area monitoring and control systems
- 2012
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Ingår i: 2012 IEEE International Energy Conference and Exhibition, ENERGYCON 2012. - : IEEE. - 9781467314541 ; , s. 927-934
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Konferensbidrag (refereegranskat)abstract
- Timely and synchronized phasor data at high resolutions holds a great promise for more responsible and advanced power grid operations. It is expected that the combined effort of developing new application paradigms and the supporting Information and Communication Technology (ICT) will enable the evolutionary change for future transmission grid operation. This paper addresses the design of the supporting ICT system for Wide-Area Monitoring and Control applications considering system performance. The major contribution that distinguishes this paper from previous research efforts in the same area is that this study quantifies the end-to-end data delay and the received packet rate with considerations of different levels of data concentrations. The analysis performed in this paper is not merely limited to the performance issues caused by communication networks but also provides means to view and analyze the overall data delay of the entire supporting ICT system.
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| 65. |
- Zhu, Kun, et al.
(författare)
-
ICT architecture impact on wide area monitoring and control systems' reliability
- 2011
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Ingår i: IEEE Transactions on Power Delivery. - 0885-8977 .- 1937-4208. ; 26:4, s. 2801-2808
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Tidskriftsartikel (refereegranskat)abstract
- Timely and accurate data with high resolutions holds great promise for more responsible and advanced power grid operations. The research has been focusing on design of monitoring and control scheme given the assumptions that the supporting information and communication technology (ICT) systems are capable of providing data and perform control with sufficient quality. A relatively less addressed aspect is the dependency of wide-area monitoring and control (WAMC) systems on their supporting ICT architecture which is usually a compromise between various concerns, such as data quality, interoperability, or security. Without an appropriate ICT architecture design, the projected WAMC system functionalities run the risk of being jeopardized. This paper begins with a presentation about possible delays brought by complex data-transfer and processing processes. Analytical experiments are conducted with purposes to quantify the maximum delay and input signal's sensitivity toward delay on a typical WAMC application where the control of static var compensation (SVC) is coordinated with generator excitations using phasor measurements. Given the characteristics of this particular control scheme, two possible ICT architectures that provide data with different qualities are compared concerning the reliability of this WAMC application. This paper concludes by proposing a generic ICT architecture, enabling efficient WAMC systems implementation in terms of data quality.
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| 66. |
- Zhu, Kun, et al.
(författare)
-
ICT system performance impact on wide area monitoring and control systems
- 2012
-
Ingår i: 44th International Conference on Large High Voltage Electric Systems 2012. ; , s. 1-10
-
Konferensbidrag (refereegranskat)abstract
- Timely and accurate data with high resolutions holds great promise for more responsible and advanced power grid operations. The research has been focusing on design of monitoring and control scheme given assumptions that the supporting Information and Communication Technology (ICT) systems are capable to provide data and perform control with sufficient quality. A relatively less addressed aspect is the dependency of Wide area monitoring and control (WAMC) systems on their supporting ICT architecture which is usually a compromise between various concerns, such as data quality, interoperability or security. Without an appropriate ICT architecture design, the projected WAMC system functionalities run the risk of being jeopardized. This paper begins with a presentation about possible delays brought by complex data transfer and processing processes. Analytical experiments are conducted with purposes to quantify the maximum delay and input signal's sensitivity towards delay on a typical WAMC application where the control of Static Var Compensation (SVC) is coordinated with generator excitations using phasor measurements. Given the characteristics of this particular control scheme, two possible ICT architectures that provide data with different qualities are compared concerning the reliability of this WAMC application. The paper is concluded by proposing a generic ICT architectures enabling efficient WAMC systems implementation in terms of data quality.
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| 67. |
- Zhu, Kun, 1983-, et al.
(författare)
-
Investigation of data exchange requirements for cooperative grid planning and operation
- 2011
-
Konferensbidrag (refereegranskat)abstract
- IEC 61970 and 61968 together referred as Common Information Model (CIM), are proposed to facilitate integration of EMS applications with proprietary data formats and information exchange between control centers. To use Information and Communication Technology (ICT) systems in an optimized manner, it is necessary to partition the potentially voluminous data into subsets given their sources, expected exchange frequency, and subscribing applications. In response to these requirements, the concept of CIM profiles is brought up by CIMug. In this paper, functions illustrating the dependency between exchange data volume and basic grid parameters for each data profile are presented. A CIM/XML/RDFfile for a commonly available 40 bus test system modeled according to CIM 13 together with examples provided by standards are used as references. The method is validated by estimating the CIM/XML/RDF file sizes of similarly available 100 bus and 60 bus test systems. The contribution of this paper is that it provides ICT system designers with a means to estimate the corresponding requirements for various CIM based data exchange scenarios. The estimations are performed based on commonly known grid parameters such as number of buses, branches, generators, transformers and loads.
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| 68. |
- Zhu, Kun, 1983-, et al.
(författare)
-
Test platform for synchrophasor based wide-area monitoring and control applications
- 2013
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Ingår i: Power and Energy Society General Meeting (PES), 2013 IEEE. - Vancouver : IEEE. - 9781479913039 ; , s. 6672308-
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Konferensbidrag (refereegranskat)abstract
- Synchrophasor technology is considered as a main enabler for the envisioned Smart Grid at the transmission level. Despite some preliminary field test results reported from China Southern Grid, the majority of the synchrophasor applications are still in the engineering or advanced laboratory tests phases. One possible impedance of any real-life adoption of such applicationsis a lack of test platforms that are able to verify the proposed application paradigms in cost efficient manners, and also to demonstrate the interactions between the power system and the supporting ICT systems with sufficient details. In this paper, we report on the continuing research efforts targeting at developing a test platform for the development of the synchrophasor based applications. The platform incorporates a virtual Phasor Measurement Unit (PMU), a real-time simulator for power systems, a real-time simulator for communication networks, and an implementation of an open-source Phasor Data Concentrator. Specifically, this article focuses on the implementation and verification of the virtual PMU, and on the extension of its functionality to incorporate communication over UDP.
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| 69. |
- Zhu, Kun, et al.
(författare)
-
To concentrate or not to concentrate : Performance analysis of ICT system with data concentrations for Wide-area Monitoring and Control Systems
- 2012
-
Ingår i: Power and Energy Society General Meeting, 2012 IEEE. - : IEEE. - 9781467327275 ; , s. 6344977-
-
Konferensbidrag (refereegranskat)abstract
- Timely and synchronized phasor data at high resolutions holds great promise for more responsible and advanced power grid operations. It is expected that combined effort of developing new application paradigms and the supporting Information and Communication Technology (ICT) will enable the miracle of Smart Grid at the transmission level. This paper addresses the design of the supporting ICT system for Wide Area Monitoring and Control applications from the performance perspective. The major contribution that distinguishes this paper from previous research efforts in the same area is that this study quantifies the end-to-end data delay with consideration of different levels of data concentrations. The analysis performed in this paper is not limited to the delay caused by individual ICT components but also provides means to view and analyze the delay of the entire supporting ICT system. Moreover, the quantified delay results drawn in this paper will potentially provide valuable input to the discussion on the coming standards for synchronized phasor measurements.
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| 70. |
- Zhu, Ying, et al.
(författare)
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Effects of divalent copper on tetracycline degradation and the proposed transformation pathway
- 2020
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Ingår i: Environmental Science and Pollution Research. - : Springer. - 0944-1344 .- 1614-7499. ; 27:5, s. 5155-5167
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Tidskriftsartikel (refereegranskat)abstract
- To reveal the characteristics of tetracycline (TC) photocatalytic degradation under Cu(II) coexistence, effects of Cu(II) on TC photocatalytic degradation by ZnO nanoparticles (ZnO NPs) as a function of pH, humic acid (HA), and initial Cu(II) concentration were investigated. Interaction of TC with Cu(II) in the treatment process was analyzed by circular dichroism (CD) spectroscopy, while TC degradation pathway was investigated by high-performance liquid chromatography-mass spectrometry. Sixty-five percent and ninety-one percent TC degradation within 60 min in the absence and presence of Cu(II), respectively, was reported. Both adsorption and photocatalytic degradation of TC under Cu(II) coexistence increased with increasing pH from 3 to 6, while decreased with further increase in pH. HA inhibited the degradation of TC by ZnO NPs both in the presence as well absence of Cu(II), while TC degradation decreased from 91 to 73% and from 73 to 37% in the presence and absence of Cu(II), respectively. TC degradation by ZnO NPs first increased then decreased with increasing Cu(II). Maximum TC degradation (about 94%) was obtained in the optimum concentration range of Cu(II) (0.05-0.15 mmol/L). In addition, there was a lag effect between TC adsorption and degradation on ZnO NPs. TC degradation was improved via Cu(II)-TC surface complexation and followed N-demethylation and hydroxylation routes. This study could be of potential importance in extrapolating the transformation of TC or other antibiotics under the coexistence of heavy metals in water.
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