Abstract: The present disclosure provides a synchronization control method and system for a microgrid group. The synchronization control system for a microgrid group includes a central controller, and the central controller is configured to: receive a voltage measurement value at a grid connection point from each of the plurality of microgrids; perform proportional-integral adjustment on the voltage measurement value to obtain a difference between the voltage measurement value at a previous moment and a control value at a current moment, so as to estimate a control instruction at a next moment for each microgrid; and send a control instruction to at least one microgrid of the plurality of microgrids, to adjust closing synchronization between the plurality of microgrids through phase lock control. The accuracy and timeliness of the collected data and the effectiveness of the control can be ensured, which greatly improves a success rate of synchronization closing of the microgrid group.

Abstract: This specification provides a method and an apparatus for estimating a word segment frequency in differential privacy protection data, and an electronic device. According to the method, each piece of word segment information that is reported by a terminal device and that is subject to local differential privacy processing is obtained; N groups of word segment information are obtained through division, so each piece of word segment information of the same group corresponds to the same target quantity; each group of estimated data that is corresponding to each group of word segment information and that represents unbiased word segment frequency estimation is determined; and each layer of nodes of a prefix tree used to record a word segment frequency is generated layer by layer based on each group of estimated data.

Abstract: The present invention discloses a surge protection circuit. The surge protection circuit is formed by serially connecting a piezoresistor, a discharge tube and a differential mode (DM) inductor. The present invention fully utilizes characteristics of the DM inductor, effectively suppresses electromagnetic interference, and can also effectively avoid damage caused to a surge protection element by over-voltage and over-current shocks, reduce a residual voltage, and prolong the service life of a related electronic product.