Web Services is a platform which enables the applications interoperate on the Internet. It is widely used in designing and building systems in open and dynamic distributed environments such as EAI (Enterprise Application Integration) and B2B (Business to Business). As the development of framework technology, it is convenient and standardized to use framework to develop web applications. For Web Services, the frameworks Axis, Axis2, XFire and CXF are widely used. By the performance testing of the four frameworks, this paper not only introduces the four framework but also analyzes the differences of the four frameworks, and then makes some suggestions for developers to choose the appropriate one. The framework can simplify the development process and decrease the development time. However, because of the differences of the frameworks, the interoperation between different web service's server and client may cause incompatible problems. This paper analyzes the reasons of this incompatible problems and finally presents a mechanism based on unified invoking component to solve this problems. By parsing and repacking the SOAP messages, the incompatible problems between client and server can be solved successfully.

With the highly strict demand of data synchronicity in the protective device of substation, the merging unit's synchronization delay, from data collecting to data sending, should be both short and stable. However, the calibration time is usually not precise in current substations. In order to solve the problem that sampling data is not synchronous, this paper designs a kind of system using FPGA based on Newton interpolation algorithm. This algorithm takes advantage of sampling information of the merging unit's accurate arriving time and packet's delay time to calculate the corresponding sample in local time. Then it can get the sample information of different merging units at the same local time using interpolation calculation. Compared with the traditional way, this method realizes sample value synchronization without external synchronous clock source. This system receives data from multiple merging units, and then sends to bay layer unit to use after data synchronization. In power system, the processed delay of sample value is less than 10us, which is really difficult for CPU. So FPGA is used in this system. Being adopted modular design to make each sub-module collateral execution, the speed level is ns. The simulation and experiment results demonstrate the validity of the proposed method, and this system is very meaningful and important to the automation development of the power system.

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Dispatching automation system is the nerve center of power grid. When