The problem of increasing the reliability of systems of control and accounting of electric energy consumption at the enterprises of mining industry, the method of increasing the reliability by redundancy method with further replacement of failed elements are considered. An example of practical calculation of reliability with loaded duplication and restoration of elements of the system of control and accounting of electric energy consumption is given, as a result of which the expediency of application of the proposed method is proved.
The necessity of forming the specified starting characteristics of stationary plants of mining enterprises with synchronous drive of medium and high power is shown. The synchronous motor with excitation system with two-way converter is considered. This excitation system meets the technical requirements for the considered types of drives. When starting and self-starting the motor, the bilateral converter is used as an inverter, and during synchronous operation as a controlled rectifier. At the same time, its operating mode depends on the voltage level in the supplying network and the value of the current induced in the field winding of the motor. It seems necessary to consider the issues of stable operation of the two-way converter in the inverter mode and to investigate the motor starting characteristics with this system in order to obtain the corresponding analytical dependences and calculation methods. Idealized dependences of the maximum value of the inverted current on the control and commutation angles and the parameters of the power transformer were obtained. When analyzing these dependences, it is determined that in real conditions, the maximum value of the control angle at the same parameters of the power transformer and the value of current i f is less than in the idealized ones.
