| Popis: |
The paper considers the possibility of using capacitive power take-off from medium voltage overhead power lines with isolated neutral. Direct scaling of the designs of the known 1-phase capacitive power take-off devices intended for high voltage overhead power lines is impractical for several reasons: the impossibility of obtaining significant power, violation of the operating conditions of protection against single-phase earth faults, the creation of asymmetry of phase voltages relative to the ground. As a power take-off device, it is proposed to use a 3-phase symmetrical circuit of a capacitive voltage divider with a voltage converter at the output, which makes it possible to minimize the indicated disadvantages. On the basis of computer simulation of the equivalent circuit of an overhead line section with a power take-off device, its external characteristics were obtained for various values of the capacitance of the voltage divider capacitors. The simulation results confirm the technical feasibility and feasibility of using the proposed power take-off method for feeding low-power 1- and 3-phase consumers. |
