Research And Optimized Design Of High Performance Multistage Depressed Collector

TWT is widely used in radar systems, microwave communications, electronic warfare and satellite systems because of the high efficiency, low noise, wide-band, highpower field. In recent years, solid-state devices were developed rapidly, but due to the above advantages, the status of traveling wave tube remains unshakable. Efficiency is the basic technical indicator of TWT, people are always in constant pursuit of high efficiency, especially in the space environment, the energy is not easy to obtain. The multi-stage depressed collector is a key technology to achieve high efficiency TWT, so designed high-performance collector quickly for traveling wave tube has an extremely important role.The design of collector is primarily to determine the size and shape of the model, but the model is how to design out step by step was rarely mentioned in the literature. This paper focuses on the structural design of the collector, put forward a complete design and optimization process and verified this process use the microwave tube simulator software packages(MTSS). The main research content of this paper includes the following several aspects:1. This paper start from the movement of the electrons since they move into the depressed collector area, expounds the working principle of the collector. Then talk about how to add the magnetic of the refocusing region from the state of the electronics when they moved to the entrance of the collector. At last, describe the elements of the design process to improve the efficiency of the collector should be noted as well as suppression of secondary electrons means.2. This paper analysis the entire design process of collector in detail, and put forward two design processes. The first is called the from scratch-type, the specific process is as follows: Select the appropriate stages according to the initial electronic state of the collector entrance and calculate the initial voltage of the corresponding stages; choose the most simple cylinder model to trace the electron trajectory; according to the results to determine the maximum possible levels of heat dissipation power, in combine with the material characteristics determine the required radiating area levels, according to the size requirements we can select the radial dimension then determined the initial length of the corresponding stages; according to the initial value by the collector inlet electronic state modeling, observations of the electron trajectory towards; then constantly optimize and adjust collector structure and the voltages of the stages according to the characteristics of the high-performance real collector and the electron trajectory, until achieve the higher performance requirements. The second is called the rapid design type, the biggest difference between the second and the first type is that the second one is designed base on an existing collector model. From the electronic states of the inlet collector access to the electronic largest track radius so we can determine the minimum hole radius of all stages, and then determine the possible range according to the electronic energy; then adjust the existing model’s parameters, then we can carry on the optimum design base on this model.