The Synchronization Transceiver Design and Experimental Verification for the LuTan-1 SAR Satellite

The deviation between the two oscillators in BiSAR systems will cause a residual modulation of echo signal. Therefore, the phase synchronization is an important issue that must be addressed for BiSAR systems. An advanced non-interrupted phase synchronization scheme is used for the LuTan-1 SAR satellite. The synchronization transceiver (STR) is designed for transmitting and receiving synchronization signals. In addition, STR mainly consists of master and auxiliary transceivers and switch module. Furthermore, the function and working principle of STR are introduced, and the detailed design of each part is described. The measured results are also evaluated to prove the performance of the STR. In addition, the phase synchronization accuracy is also demonstrated to verify the effectiveness of the non-interrupted synchronization scheme. The standard deviation (STD) of the residual phase is less than 0.3 degrees. The results have guiding significance for the synchronization unit design of LuTan-1 and the future BiSAR system.

Automatic Synchronverter: Inverter Lacking a Devoted Synchronization Unit

The design of self-synchronized synchronverter is made by removing the keen synchronization unit. Synchronization with the grid takes place before connection and it will track the grid frequency after connection. Like the original synchronverter it functions in various modes to deliver the grid frequency as the reference frequency. The functions of frequency regulation, voltage regulation, real and reactive power control are maintained. Moreover, it can share the real power and reactive power accurately. Distributed energy sources delivers the major contribution to the power system operation. Generally the renewable sources are non-linear and uncontainable. Majority of renewable energy sources were associated to power systems through dc/ac converters. For this kind of application synchronizing the inverter with the grid is necessary before and after the connections to be made. It is one of the biggest challenges. So synchronverter is designed to deliver a scheme for power systems to regulate the renewable energy connected to the grid and enables smart grid integration.