Abstract: A dynamic simulation test platform for ultra-high-speed evacuated tube magnetic levitation (maglev) transportation includes an evacuated tube having a transition section and a vacuum section, a vacuum maintaining system, a motor supporting platform, and a model train. One end of the evacuated tube is provided with a first isolation door, and the other end is closed. A second isolation door is provided inside the evacuated tube. The vacuum maintaining system is connected to the transition section and the vacuum section. The motor supporting platform is provided in the evacuated tube and extends outside the transition section. The motor supporting platform is provided with a stator winding and a permanent-magnet track. A mover and a cryogenic dewar are provided at a bottom of the model train. The cryogenic dewar is provided with a superconducting bulk. A test method using the test platform is further provided.

Abstract: The present invention discloses a method for detecting open phase of a startup/standby transformer based on optical CT. A startup/standby transformer in a power plant is in a no-load condition for a long time as a standby power supply. Once a single-phase open phase fault occurs, there is no significant change in the voltage phasor and voltage sequence component of each side. If not found in time, the defect may pose a great threat to the safe operation of the power plant. In the present invention, the optical CT is used to detect a three-phase current of the high-voltage side of the startup/standby transformer. If the current satisfies an open phase criterion, it is determined that an open phase fault occurs, and then, an alarm signal is given after a delay and an operator is informed to handle the fault in time. Therefore, the operation reliability of the startup/standby transformer system in the power plant is enhanced.

Abstract: The present invention discloses a method for detecting open phase of a startup/standby transformer based on optical CT. A startup/standby transformer in a power plant is in a no-load condition for a long time as a standby power supply. Once a single-phase open phase fault occurs, there is no significant change in the voltage phasor and voltage sequence component of each side. If not found in time, the defect may pose a great threat to the safe operation of the power plant. In the present invention, the optical CT is used to detect a three-phase current of the high-voltage side of the startup/standby transformer. If the current satisfies an open phase criterion, it is determined that an open phase fault occurs, and then, an alarm signal is given after a delay and an operator is informed to handle the fault in time. Therefore, the operation reliability of the startup/standby transformer system in the power plant is enhanced.

Abstract: A combined mobile cart for the sick or wounded, includes a mobile cart and a mobile stretcher. The mobile cart includes a main body frame, a left retractable track mechanism, a right retractable track mechanism, a lifting and translating mechanism, and an automatic movable weight-balancing mechanism. The top of the main body frame is provided with the left and right retractable track mechanisms, a supporting layer is arranged in a middle of the main body frame of the mobile stretcher, and the automatic movable weight-balancing mechanism is arranged at a bottom of the main body frame; and the lifting and translating mechanism is provided with a left case body and a right case body, lifting ropes are arranged under the lifting and translating mechanism, and suspension tools are connected with the lifting ropes, so that functions of vertically lifting and vertically moving the mobile stretcher are realized.

Abstract: A method and apparatus for identifying an open phase of a circuit breaker on the basis of voltage. The method comprises: a protection apparatus measures three-phase voltages at two sides of a circuit breaker; respectively calculates a vector difference and an effective value of the voltages at two sides of the circuit breaker; when the phase voltages at two sides are both greater than 80% to 90% of a rated voltage, and the voltage vector difference at two sides of the one-phase or two-phase circuit breaker is greater than a set voltage, it is determined that the circuit breaker has an open phase; and actuates an alarming or tripping operation after a short time delay t.

Abstract: A combined mobile cart for the sick or wounded, includes a mobile cart and a mobile stretcher. The mobile cart includes a main body frame, a left retractable track mechanism, a right retractable track mechanism, a lifting and translating mechanism, and an automatic movable weight-balancing mechanism. The top of the main body frame is provided with the left and right retractable track mechanisms, a supporting layer is arranged in a middle of the main body frame of the mobile stretcher, and the automatic movable weight-balancing mechanism is arranged at a bottom of the main body frame; and the lifting and translating mechanism is provided with a left case body and a right case body, lifting ropes are arranged under the lifting and translating mechanism, and suspension tools are connected with the lifting ropes, so that functions of vertically lifting and vertically moving the mobile stretcher are realized.

Abstract: A method and apparatus for identifying an open phase of a circuit breaker on the basis of voltage. The method comprises: a protection apparatus measures three-phase voltages at two sides of a circuit breaker; respectively calculates a vector difference and an effective value of the voltages at two sides of the circuit breaker; when the phase voltages at two sides are both greater than 80% to 90% of a rated voltage, and the voltage vector difference at two sides of the one-phase or two-phase circuit breaker is greater than a set voltage, it is determined that the circuit breaker has an open phase; and actuates an alarming or tripping operation after a short time delay t.