Constant voltage transmission

The discussion of a new and but slightly tested method of operation of transmission lines should first deal with the fundamental questions: Has the method large advantages? Is its cost low? Is it reliable? In the present paper, the aim has been to discuss from the above points of view a method of control of transmission lines by means of synchronous motors. Advantages. The obviously great advantage is offered of steady voltage at all places and under all conditions of load. This is in sharp contrast with practically all modern transmission systems, where the voltage at some part varies with every change in load. Cost. As the carrying capacity of a transmission line can be doubled or trebled by this method of control, the saving in line construction will in many cases more than offset the cost of the additional machinery required. Reliability. Although loaded synchronous motors are often regarded as an unreliable part of a transmission system, the objection does not apply to unloaded synchronous condensers, and the new method is stated in the paper to be more reliable than the usual method of operating transmission lines. By increasing the economical distance of transmission, this method would hasten the growth of the extensive high-tension networks which are already spreading over large sections of the country. The advantages and disadvantages of the new method are summarized at the end of the paper, and sample lines are worked out.