System control and safety reliability are important links of the marine DC (Direct Current) power system. The simulationmodel is built by Matlab/Simulink, the battery and super-capacitor are supplied to the system thr...System control and safety reliability are important links of the marine DC (Direct Current) power system. The simulationmodel is built by Matlab/Simulink, the battery and super-capacitor are supplied to the system through a three-phase interleaved DC/DCconverter, the fuse and disconnector switch combination are used as the protection device, and the short-circuit point is set betweeneach branch and the DC distribution board, performing short-circuit simulation. This paper also proposes a short-circuit calculationmethod for super-capacitors based on the simplified model of series RC (Resistors & Capacitors), and verifies its correctness throughsimulation data. The results show that the introduction of a three-phase interleaved DC/DC converter reduces the current ripple andmakes the system control more convenient;short-circuit calculation and simulation have determined the short-circuit withstandcapability of the DC distribution board, and verified the feasibility of the fuse selection method and the short-circuit calculation methodof the super-capacitor. This provides reliable verification for the application and calculation of the actual project.展开更多
The induced electricity of 110 kV transmission lines which cross the UHV AC transmission lines may threaten personal safety of the maintenance staff. In this paper, field measurement of the induced voltage and induced...The induced electricity of 110 kV transmission lines which cross the UHV AC transmission lines may threaten personal safety of the maintenance staff. In this paper, field measurement of the induced voltage and induced current on a 110 kV crossing line inside Jinhua in Zhejiang province is performed. The electrostatic induced voltage on the measured line is 12.24 kV. The power frequency electromagnetic field simulation model is established, and the calculation results are consistent with the measured. Influence factors analysis shows that the electrostatic induced voltage on the 110 kV line is 12.78 kV, the electromagnetic induced voltage is 12.3 V, the induced current through ground wire is less than 1A when the UHV lines operate at full load. The induced voltage and current decrease while the crossing distance increases. Parallel lines induction is much higher than crossing lines. The electromagnetic induced voltage after ground knife-switch shut down would exceed the human safety voltage 36 V while the crossing angle is less than 30?, so the temporary ground wire must be hanged to ensure safety of the maintenance staff.展开更多
文摘System control and safety reliability are important links of the marine DC (Direct Current) power system. The simulationmodel is built by Matlab/Simulink, the battery and super-capacitor are supplied to the system through a three-phase interleaved DC/DCconverter, the fuse and disconnector switch combination are used as the protection device, and the short-circuit point is set betweeneach branch and the DC distribution board, performing short-circuit simulation. This paper also proposes a short-circuit calculationmethod for super-capacitors based on the simplified model of series RC (Resistors & Capacitors), and verifies its correctness throughsimulation data. The results show that the introduction of a three-phase interleaved DC/DC converter reduces the current ripple andmakes the system control more convenient;short-circuit calculation and simulation have determined the short-circuit withstandcapability of the DC distribution board, and verified the feasibility of the fuse selection method and the short-circuit calculation methodof the super-capacitor. This provides reliable verification for the application and calculation of the actual project.
文摘The induced electricity of 110 kV transmission lines which cross the UHV AC transmission lines may threaten personal safety of the maintenance staff. In this paper, field measurement of the induced voltage and induced current on a 110 kV crossing line inside Jinhua in Zhejiang province is performed. The electrostatic induced voltage on the measured line is 12.24 kV. The power frequency electromagnetic field simulation model is established, and the calculation results are consistent with the measured. Influence factors analysis shows that the electrostatic induced voltage on the 110 kV line is 12.78 kV, the electromagnetic induced voltage is 12.3 V, the induced current through ground wire is less than 1A when the UHV lines operate at full load. The induced voltage and current decrease while the crossing distance increases. Parallel lines induction is much higher than crossing lines. The electromagnetic induced voltage after ground knife-switch shut down would exceed the human safety voltage 36 V while the crossing angle is less than 30?, so the temporary ground wire must be hanged to ensure safety of the maintenance staff.
