RU2166241C2 - Accelerator incorporating high-frequency power supply - Google Patents

Abstract

FIELD: high-frequency magnetron supplies for charged-particle accelerators. SUBSTANCE: Accelerator has its generator and sections isolated by means of circulator; generator is connected to input arm of circulator whose second arm is connected to resonance (standing-wave) section and third arm, to mismatching device and to matched load through phase shifter; resonator whose resonant frequency equals accelerating section frequency is connected to fourth arm. EFFECT: enhanced magnetron frequency stabilization factor. 1 dwg

Description

 The present invention relates to high-frequency power systems for particle accelerators, specifically to high-frequency power systems for resonant accelerators from magnetrons.

 A device is also known in which a ferrite circulator is used to decouple the magnetron generator and the resonator section. In the device, the magnetron is connected to the first arm of the circulator, the resonant accelerating section is connected to the second arm of the circulator, and an absorbing load is connected to the third arm of the circulator [1]. The circulator is designed to decouple the oscillator (magnetron) and high-Q section, which ensures its excitation at the operating frequency.

 The disadvantage of this device is the lack of stabilization of the frequency of the generator due to the complete isolation of the generator and the high-Q section.

 A device is also known in which a ferrite circulator is used to decouple the magnetron generator. In the device, the magnetron is connected to the first arm of the circulator, the resonant accelerating section is connected to the second arm of the circulator, the phase shifter, the mismatch, and the absorbing load are connected to the third arm of the circulator [2]. When using a four-arm circulator, a short circuit is established in the fourth shoulder, which provides full reflection of power. The circulator is designed to decouple the generator and the section, and the presence of a mismatch in the third arm of the circulator provides the creation of a feedback channel that allows stabilization of the frequency of the generator. The magnetron frequency stabilization coefficient, defined as the ratio of the oscillator frequency deviations during operation to the matched load to the frequency deviations when the generator operates in the RF system, is 10–12. It is impossible to increase the stabilization coefficient by increasing the signal in the feedback channel due to violation of the conditions of single-frequency excitation magnetron.

 The disadvantage of this device is the insufficient value of the coefficient of stabilization of the frequency of the generator due to the limitation on the value of the feedback signal.

 The objective of the invention is to increase the coefficient of stabilization of the magnetron frequency. The technical result is achieved by the fact that in the accelerator with the isolation of the generator and the sections with the help of a circulator, in which the generator is connected to the input arm of the circulator, the resonator section (section with a standing wave) is connected to the second arm of the circulator, and a mismatch and coordinated signal are connected to the third arm of the circulator load, a resonator having a resonant frequency equal to the frequency of the accelerating section is connected to the fourth arm.

 The drawing shows a functional diagram of the proposed device.

 Magnetron 1 is connected to the first arm of the circulator 2, the resonator section 3 is connected to the second arm of the circulator, the phase shifter 4, the mismatch 5 and the matched load 6 are connected to the third arm of the circulator 3, and the resonator 7 is connected to the fourth arm of the circulator, having a resonant frequency equal to the accelerating frequency sections.

 The device operates as follows. The wave reflected from section 3 enters the third arm and, partially reflected from the mismatch 5, is transmitted to the fourth arm of the circulator to the input of the resonator 7.

 The resonator 7 has a load factor equal to or higher than that of the accelerating section 3. The frequency of the resonator 7 is equal to the frequency of the accelerating section 3. In this case, in the feedback channel, the wave, reflected from two high-quality objects (resonator section 3 and resonator 7), arrives at the input of the magnetron and ensures the tightening and stabilization of its frequency. The phase shifter 4 is designed to set the optimal phase of the reflected wave at the input of the magnetron 1. The resonator 7 must operate in the non-coupling mode, so that the phase shift in the feedback channel has characteristics that provide single-frequency excitation of the magnetron at the operating frequency.

 The proposed device allows to increase the frequency stabilization coefficient by 30 - 50% due to the increase in comparison with the prototype of the fixing effect of the signal reflected from two high-quality loads on the magnetron generator.

Sources of information
1. Lebedev I.V. Microwave engineering and instruments, vol. 2, M .: Higher school, 1972.

 2. Gory H.R. Network for Pulling a Microwave Generator to the Frequency of its Resonant Load - USA patent 3714592, 1973.

Claims (1)

 An accelerator with a decoupling of the generator and a section using a circulator, in which the generator is connected to the input arm of the circulator, a resonator section (section with a standing wave) is connected to the second arm of the circulator, an mismatch and a coordinated load are connected to the third arm of the circulator, characterized in that the fourth arm is connected to a resonator having a resonant frequency equal to the frequency of the accelerating section.