3results about How to "Accurate protection" patented technology

This application provides a 550kV vertical structure insulated metal-enclosed switchgear, belonging to the technical field of enclosed switchgear. The technical solution is a 550kV vertical structure insulated metal-enclosed switchgear, including an insulating bushing electrically connected to an isolating grounding switch. A vertical tank for closing resistors is located outside the isolating grounding switch, containing a closing resistor. Two parallel vertical tanks for vacuum interrupters are located outside the closing resistor tank, each containing a 252kV vacuum interrupter, and each 252kV vacuum interrupter is connected in parallel with a capacitor. The moving contacts of the two 252kV vacuum interrupters are connected in series via a connecting conductor. A driving mechanism is located at the bottom of both the closing resistor tank and the vacuum interrupter tank, enabling synchronous opening and closing of the closing resistor and the 252kV vacuum interrupters. The beneficial effect is that it ensures synchronous closing of the 252kV vacuum interrupters connected in series.

The application relates to the technical field of crane motion control, and discloses an electric grab bucket protection system and a control method thereof, wherein the system comprises a PLC, an inductive switch, a current transformer, a grab bucket opening AC contactor and a grab bucket closing AC contactor which are electrically connected with the PLC respectively; the current transformer is used for sampling electric grab bucket current information and transmitting the information to the PLC; and the inductive switch is used for controlling whether the current transformer transmits the sampled electric grab bucket current information to the PLC. The application solves the problems of the prior art, such as the incapability of accurately controlling the opening and closing limit of the grab bucket and the poor protection effect.