Расчетная оценка безотказности многоканального преобразователя напряжения c ротацией силовых каналов
Dependability of power electronics products designed for power supply of electronic equipment, largely determine its dependability, because failure of the power supply system, as a rule, leads to failure of the equipment as a whole. Therefore, the secondary power supply must be highly reliable. To ensure the required dependability of power supplies, various methods of their construction and redundancy are used. Early stages of design determine the dependability that will be implemented in the manufacture and maintained during operation. At these stages, dependability prediction are of paramount importance.
The complexity of power supply architectures and the use of redundancy in them leads to the complexity of analytical of their dependability prediction and requires the involvement of highly qualified specialists. The use of specialized software that implements simulation modeling in the calculation of structurally complex power supplies also causes certain difficulties associated with the construction of formal models and their verification. Therefore, the improvement of analytical methods to obtain estimates of the dependability of power sources is currently being given a lot of attention.
At present, one of the promising directions of improving the reliability of voltage converters is the use of backbone-modular architecture, mixed redundancy and rotation of the major and redundant power channels. For such a converter, an analytical method for calculating the lower and upper estimate of the reliability function is proposed, which is based on the use of a standardized model for the group "sliding loaded redundancy". It is shown that the channel rotation as the reliability characteristics of the channels can be used cyclic failure rate.
In contrast to the known, the developed method allows to obtain these estimates as a function of time and taking into account the failure rates of the converter channels not only in the operating mode, but also in the standby mode.
An example of calculating the limits of the reliability function of the converter by the proposed method is given, and to confirm the results of the calculation of the same example by simulation. In addition, it is shown that the reduction of the full rotation cycle of the channels increases the uniformity of the resource consumption by the channels with an "absolutely reliable" switch and does not affect the reliability of the converter, and the "unreliable" switch leads to a decrease in reliability.