Peculiarities of Residual Current Devices (RCD) Application in Ships’ Electrical Power Network

The article analyses the technical feasibility of residual current device (RCD) application for electrical installations in ships with isolated neutral of the electrical power source. 
The device is intended to ensure the electrical safety of personnel in those power supply systems where other protective measures proved to be insufficient or unreliable, and the disconnection (de-energizing) of protected circuit section or protected group of consumers is possible in compliance with uninterruptible power supply requirements. 
The second purpose of the RCD is to ensure fire safety in case of a single-phase earth fault (or the local single-phase reduction of insulation resistance). 
The article analyses one of the possible variants of RCD integration based on the multiline principle of finding out the fact of dangerous currents flowing through the human body. Basic principles of RCD serviceability in circuits of the type under consideration are formulated. 
Results of mathematic simulation of the most unfavourable (by the values of insulation resistance-to-phase capacity ratio) regimes of the power supply system are given and recommendations are formulated for IT type supply system integration where electrical safety can be ensured by using RCD having the relevant configuration. 
Recommendations on the groups of electrical power consumers, for whose protection the residual current devices shall be used are set forward.

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UDC:  621.316.9:331.45
Author(s):  V.N. Pavlov, A.O. Trusov, V.I. Ratnikov
Pages:  235 – 254