The reliability of the control system for electric rolling stock is considered using probabilities without failure of the power traction transformer of a controlled rectifier, an autonomous inverter and a traction asynchronous electric motor presented in the form of blocks, in which the failure of the entire system, which in the theory of reliability is called a series connection of elements.
An example is given of determining the probability of normal operation of an object using the method of obtaining moments from the characteristics of blocks and a given function by sequentially calculating the mathematical expectation, standard deviation, third and fourth central moments with their expansion in a Taylor series. The probabilities of not exceeding the specified values are estimated under the assumption that the characteristics of individual blocks are independent.