Electric Energy Saving Systems for Internal Combustion Engine Run-in and Test Rigs
The production of internal combustion engines shows a constant growth. Running-in of engines on rigs and their acceptance tests are the final operations in their manufacturing process or overhaul. In view of constantly growing prices for electricity, it is economically advisable to use the effective power developed by the heat engines in the course of these operations by converting it and supplying the generated electricity in the industrial network. In view of these circumstances, engine-building works and specialized repair enterprises equip their testing stations with running-in and braking rigs (RBR) including means for recovering electricity and carry out research and development activities aimed at improving their technical and economic indicators.The article discusses various domestically produced and foreign energy saving systems intended for running-in and testing internal combustion engines at engine building and engine repairing enterprises. Preference is given to two systems that have been successfully put in use at the OAO Dagdizel Works (the city of Kaspiysk, Dagestan).In the first running-in and braking system, the energy saving method developed in 1990 is implemented. The system main elements include a group of braking devices (rigs) made on the basis of non-balanced DC machines and a group rotary converter.The study results have shown that with using the RBR system, a factor of 1.76...2.48 larger amount of active electric energy is recuperated into the industrial network, and the time taken to payback the rig in running-in the Type YaMZ-238NB engine at an engine repair enterprise is a factor3.5...4.28 shorter than in the best foreign analogues.A rig in which a single-armature converter is used as a braking device has been developed for the enterprise’s diesel laboratory. In the course of cold running-in, power to the braking device is supplied through a Grets diode bridge. During the hot running-in or testing, the braking energy is supplied to the network directly from the converter slip rings. With such a solution, it became possible not only to obtain high efficiency, but also to minimize the rig installed capacity and to produce reactive power into the enterprise network.