Xu Aidong

Fault prediction for power system based on multidimensional time series correlation analysis

Fault prediction for power equipment allows the maintenance personnel to know the operation conditions and the fault to be occurred in advance so as to reduce the risk of fault and the economic loss. The current fault prediction methods are generally based on physical model or stochastic model, which are used to evaluate the remaining life of equipment. However, in fact, there are many interference factors between grid equipment; therefore, it is very difficult to illustrate the fault characteristics by using an accurate mathematical model. Besides, there exist many problems such as uncertain mathematical model parameters and short prediction period. As such, this paper proposes a fault prediction method based on correlation analysis of multidimensional time series, which normalizes the historical time-series data of nodes in the power equipment network topology, decomposes the time series by using the time series decomposition algorithm, extracts the typical events occurred on the nodes before the key equipment fails by using one time series pattern representation method, and explores the implicit relationship between the indicator trend and the operating conditions of equipment by correlation method, with a purpose of effectively predicting the fault or impact. The test shows that this method can make the best of time series data and take advantage of the capability to analyze and express the uncertainty relation of data mining so as to accurately and effectively predict equipment faults.

Architecture design and implementation of substation dashboard oriented to O&M center

To improve the “substation owner” control mechanism and support the conversion of substation operation and maintenance (O&M) operators to “substation owner”, in this paper, an architecture of substation dashboard oriented to O&M center is designed, which brings about integration of multiple O&M systems and collaborative operations of substations. A unified information platform is established on the base of the extended IEC61970 model. An integrated monitoring and control system is built by standardizing the three-screen interactive interface including power grid monitoring screen, equipment monitoring screen, and O&M management screen, designing the multi-dimensional and multi-layer key performance indicator (KPI) system, and developing the advanced application functions including monitoring, diagnosis, operation and coordination. The substation dashboard system designed in this paper has been piloted at the Foshan 220 kV Hongxing O&M center. It simplifies the existing dashboard system, makes information standard, unifies interfaces, and promotes collaborative operations. By providing one-stop services and centralized control for O&M of substation, it makes substation more observable, measurable, controllable and evaluable.

Analysis of overvoltage caused by intermittent earth fault and its suppression method

Intermittent earth faults occur frequently in urban distribution networks, causing overvoltage in the whole system. This paper first presents the distribution characteristics of transient overvoltage caused by intermittent earth faults. Overvoltage level at the end of a sound line turns to be higher than that of the faulted line. In resonant grounding system with Petersen coil based on thyristor controlled reactor (TCR), overvoltage appears to be more severe due to response delay of compensation. Therefore, the influence on overvoltage level of Petersen coil compensation is analyzed, based on which, an overvoltage suppression method is proposed.

Discussion on the technical architecture of smart grid in Hainan

Smart grid demonstration projects are being carried out all over the world, but none of them involves integrated demonstration of large island-based power grid. This paper analyzes the demand for smart grid in Hainan, proposes a 4-layer technical architecture including generation, transmission, distribution, and consumption. On this basis, the core business of the overall technical architecture is discussed, which include intermittent energy consumption and smart disaster early warning. Then the structure and functions of the support system are introduced. Finally, the key technologies and development trends are discussed.

Unified modeling of O&M services based on generalized measurement and horizontal correlation

To improve the operation and maintenance (O&M) efficiency and equipment management, CSG developed a cockpit system used in O&M centers. This system is an integrated platform for O&M of substations. It integrates multiple disciplines, provides a unified information platform, standardizes all service interfaces, and coordinates all the services. This way, it provides one-stop support for equipment monitoring and O&M management. The cockpit could increase the O&M centers capability of troubleshooting and response speed, and reduce workload, thereby improving O&M efficiency and quality. Unified modeling of data involved in O&M centers is the prerequisite for the cockpit system. Currently, although various data is defined CIM specifications and CSGs specifications, the definitions of secondary equipment and its data are not comprehensive enough, and the data is not effectively integrated. To meet these diversified demands, this paper proposes a unified modeling method by generalized measurement and horizontal correlation with reference to CIM specifications and IEC 61850, for the purpose of separate abstraction and modeling of various classes of data, then unified modeling by means of generalized measurement and horizontal correlation, abstraction of the actual system, and finally control and management of automation data and various equipment. Then a meta model is defined based on these ideas. The metamodel contains domain knowledge and constrains the modeling to ensure that the model is set up within the domain constraints. This method increases the abstraction level of how the issues are addressed and makes it possible for the advanced application modules on the platform to focus on the logic of the issues, rather than on bottom-layer details or organization of chaotic data. This makes the development of software more efficient, correct, and faster.

Integrated Technical Planning for Regional Smart Grid

The regional smart grid demonstration project in Hainan is a comprehensive integration demonstration project involving the whole Hainan power grid. Based on smart grid construction need analysis, this paper proposes a comprehensive integrated technology framework which includes generation, transmission, transformation, distribution and charging technology of electric vehicle. Then, the content of the demonstration project is introduced later, which includes smart dispatch, smart disaster early warning systems, operation and control of smart distribution, operation and energy management of micro grid, electric vehicles. In the end, the significance of the demonstration is discussed.