Design and Development of a Precision Speed Control Electric Drive for the Guggenheim Aeronautics Wind Tunnel

The problem and solution described in this report is that of designing and building a suitable electric drive for the propeller which drives the air in the wind tunnel of the Guggenheim Aeronautics Laboratory. Specifications were written for a suitable direct current motor and a motor-generator set for furnishing the direct current, and a complete control system was designed and installed. The control system is arranged so that a minimum number of operations is required to start and stop the equipment and to adjust the speed of the propeller. All intermediate processes are automatically controlled and the equipment is interlocked so that operations can not occur out of proper sequence. Adequate protective features prevent serious injury to the equipment, even though the equipment is neither visible nor audible from the point of control. Two types of speed control are provided, one known as hand control and the other as regulated control. When under regulated control the speed of the propeller is regulated to a constant value with a high degree of precision for equipment of this size, and the value of the regulated speed can be adjusted at the will of the operator over a wide range. Speed control of both kinds may be obtained at conveniently located stations by operation of a transfer switch.