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global navigation satellite system (GNSS) carrier phase observations are two orders of higher accuracy than pseudo-range observations, and they are less affected by multipath besides. As a result, the time transfer accuracy can reach 0.1 ns, and the frequency transfer stability can reach 1×10−15 with carrier phase (CP) method, therefore CP method is considered the most accurate and promising time transfer technology. The focus of this paper is to present a comprehensive summary of CP method, with specific attention directed toward day-boundary clock jump, ambiguity resolution (AR), multi-system time transfer and real-time time transfer. Day-boundary clock jump is essentially caused by pseudo-range noise. Several approaches were proposed to solve the problem, such as continuously processing strategy, sliding batch and bidirectional filtering methods which were compared in this study. Additionally, researches on AR in CP method were introduced. Many scholars attempted to fix the single-difference ambiguities to improve the time transfer result, however, owing to the uncalibrated phase delay (UPD) was not considered, the current studies on AR in CP method were still immature. Moreover, because four GNSS systems could be used for time-transfer currently, which was helpful to increase the accuracy and reliability, the researches on multi-system time transfer were reviewed. What’s more, real-time time transfer attracted more attention nowadays, the preliminary research results were presented.

Based on the analysis of local energy internet architecture, an overall architecture of integrated energy management and control system, which consists of four layers, is proposed in this paper. The main functions and construction contents of each layer in the overall architecture are analyzed in turn, such as the control, service and transaction applications for the application layer. On this basis, a case for industrial park is discussed. The architecture proposed in this paper can be more flexible, adaptable, extensible and comprehensive than traditional solutions, satisfying the needs of local energy internet.