В статье дана сравнительная оценка регулируемых установок компенсации реактивной мощности и разработана методика выбора их параметров и мест размещения в электротяговой сети. Проведены исследование и анализ режимов работы электротяговых сетей и питающих линий энергосистем. Выделены факторы, которые в наибольшей степени влияют на энергосбережение. ; The paper presents a systematic analysis of existing methods of reactive power compensation. The study of operating modes of the systems external and traction power supply is carried out. The methodology for selecting promising compensation schemes and energy-saving in the traction networks AC electrified railway lines is offered. The comparative evaluation of prospective controlled compensation devices shows that use of seamlessly adjustable devices with unregulated condensing the battery and with parallel translator regulated with thyristor unit and with filters to reduce harmonics bond to the large capital investments. For traction networks of domestic railways payback period is more than 10-15 years. The most promising for traction power supply today is a stepwise adjustable devices of reactive power compensation. For the efficient allocation of investments in programs and projects of modernization of system traction power supply developed by the methodology of selecting parameters and places placement devices transverse compensation in the system traction power supply, which is based on the use of software systems with imitation of interconnected instant circuits moving loads of electric rolling stock.