Secondary Power System Research Articles

Precise frequency power generation from an unregulated shaft

A system for generating precise frequency power from an unregulated shaft is described. The system comprises a high-frequency variable-speed generator, a semiconductor frequency changer, an output filter, and a voltage and frequency regulator. The semiconductor frequency changer employs silicon p-n-p-n switches as the power handling components. The operation of a typical frequency changer is described, and an oscillogram is presented which verifies the performance. Also, the ability of the frequency changer to supply a lagging reactive load is illustrated. The generator described is a brushless Secsyn type. The rotor of this machine has no rotating exciting windings and is of tubular steel construction which permits very-high-speed operation. This results in a lightweight system. Voltage regulation is accomplished by controlling both the frequency changer and the excitation of the generator. This improves speed of response. The frequency regulator is open-loop with a frequency transient that is no more than wave distortion. The accuracy of the system frequency is determined entirely by the accuracy of the frequency reference which can be as high as 0.001%. Application of the system to emergency power systems, auxiliary power systems, and secondary power systems is mentioned.

Precise-frequency power generation from an unregulated shaft

A system for generating precise frequency power from an unregulated shaft is described. The system comprises a high-frequency variable-speed generator, a semiconductor frequency changer, an output filter, and a voltage and frequency regulator. The semiconductor frequency changer employs silicon p-n-p-n switches as the power handling components. The operation of a typical frequency changer is described, and an oscillogram is presented which verifies the performance. Also, the ability of the frequency changer to supply a lagging reactive load is illustrated. The generator described is a brushless Secsyn type. The rotor of this machine has no rotating exciting windings and is of tubular steel construction which permits very-high-speed operation. This results in a lightweight system. Voltage regulation is accomplished by controlling both the frequency changer and the excitation of the generator. This improves speed of response. The frequency regulator is open-loop with a frequency transient that is no more than wave distortion. The accuracy of the system frequency is determined entirely by the accuracy of the frequency reference which can be as high as 0.001%. Application of the system to emergency power systems, auxiliary power systems, and secondary power systems is mentioned.

Ground-power equipment for the support of air force weapons

THE MATERIAL that is presented in this paper was gathered during an engineering study on the same subject which was made for the Air Research and Development Command of the United States Air Force. The objective of the study was preparation of recommendations for needed development in the area of ground support for secondary power. In aviation terminology, secondary power is defined as that power which is used for purposes other than the propulsion of aircraft and missiles. Aircraft and missiles are defined as weapons, and a weapon system includes everything that is needed for maintenance, calibration, testing, and training during operational use of the weapon. “Ground power” substitutes for air-borne secondary power during tests. The familiar secondary power systems are electric, hydraulic, and pneumatic. During the study, it was found desirable to treat air conditioning as a fourth and newly important type of secondary power.

Ground power equipment for support of air force weapons

THE MATERIAL that is presented in this paper was gathered during an engineering study on the same subject which was made for the Air Research and Development Command of the United States Air Force. The objective of the study was preparation of recommendations for needed development in the area of ground support for secondary power. In aviation terminology, secondary power is defined as that power which is used for purposes other than the propulsion of aircraft and missiles. Aircraft and missiles are defined as weapons, and a weapon system includes everything that is needed for maintenance, calibration, testing, and training during operational use of the weapon. ?Ground power? substitutes for air-borne secondary power during tests. The familiar secondary power systems are electric, hydraulic, and pneumatic. During the study, it was found desirable to treat air conditioning as a fourth and newly important type of secondary power.