Launch and control circuit systems built on traditional devices represent complicate multi-link system. Its liability is determined by a number of intermediate devices. Launch jaggedness – is one of the significant flaws, negatively affect on launching process dynamics. Promising direction of launch and control circuits devices are rheostats built on high current semi-conduct polycrystalline thermistors. At the article short analysis of electrotechnical devices launch processes is given. A power engines launch process with thermistor rheostats is considered and formulated a number of limits. Graphic dependences characterizing launch current and rotating moment at direct launch changing and with rheostats on thermistors are given. An example of launch current for asynchronic engine with phase rotor calculating is given as well.
Keywords: semiconducting thermos-resistance, launch rheostat, launch currents curves, generalized constant, automation.
Application of low-power thermal resistors in starters requires availability of intermediate equipment and various components. It significantly reduces the reliability of the equipment. Increase in currents flowing through the pre-regulating devices simplifies electrical schematic of the control and regulation. To use thermal resistors in circuits with high currents it is necessary to use special designs, for the purpose of thermoresistor's material overheating prevention. Algorithms for synthesis of starting rheostats are given. The dependences characterizing different starting models are given.
Keywords: semiconductor thermal resistance, starting current models, generalized current characteristics
Electrotechnical devices starting processes short analysis is done including limited power autonomous system. The electrical installation starting processes with thermistor rheostats character depend on considered and formulated number of restrictions. The graphic depending’s are given characterizing different start models. The recommendations are given to form optimal starting processes with rheostats built on semiconductors polycrystalline thermistors.
Keywords: semiconductor thermoresistance, electrical installation, starting current, starting model, starting rheostat, starting processes dynamics
This article presents the results of computer simulation of electromechanical phase splitter working at idle mode based on a three-phase induction motor type HVA-55 with squirrel cage type rotor. Simulation made on the basis of previous studies of the auxiliary electric drives onboard of AC electric locomotives. These studies include: the development of a mathematical model of the three-phase induction electric machine that is suitable for describing the dynamics of electromagnetic, electromechanical and thermal processes under unbalance the power supply voltage, and also at not equal parameters at the each phase of machine; the development of computer models of various schemes of auxiliary electric drives of AC locomotives, having in its composition induction motor mathematical model. It has been demonstrated that the selected mathematical model of the induction machine can adequately describe the phase splitting process: the conversion of single-phase AC catenary voltage to three-phase voltage for auxiliary loads feeding.
Keywords: induction motor, mathematical model, electromechanical phase splitter, idle mode, AC electri locomotive, electric auxiliary drive, working capacity, start-up capacity, rotor, stator winding phase