The Design And Application Of Medical Synchrotron Cooling Water Control System

As an important component of the medical synchrotron devices, the cooling water system works as a energy carrier to take away the excessive energy which produced during the synchrotron operation in order to guarantee the normal operation of the accelerator in stable temperature. As the medical synchrotron itself is a huge device, and the numbers of the magnets and power supply and related devices inside is large, the components which required to be cooled have different requirement to the temperature, pressure and water quality to the cooling water, which makes the design and construction of the cooling water become a more complicated project, and also increases the control requirement to the cooling water system. In order to make the control system running more stable, we need to consider many factors.Based on the theory of medical synchrotron, this dissertation aims to research the operation status of the internal components of the accelerator. The heat generation method, heat power will be the reference to the cooling water temperature and flow control.During the designing of the cooling water system, combining with the accelerator system structure and the requirement of each part to the cooling water to design the cooling water control system structure and the control flow and monitoring control software; according to the specific condition, the control instrumentation will be selected; and analyze and research related control operation and stable control solution of the cooling water system under the each operation status of the accelerator systems.In the system installation and commissioning process, we attempt a variety of methods to improve the control stability. Finally it achieves a relatively good control effect as below(1) For the site layout, the system control structure is divided into seven sections to set up the DCS control system.(2) Use a three-cycle structure control method and considering about the different seasons to achieve energy-saving.(3) For synchronous ring system load characteristics of a large conversion rate, explore the rate of change through the load statistics and operating rules, using PID control methods, dual PID mode switching method and cascade control method.By commissioning, we confirm the system’s temperature reaches the good control effect by using cascade control mode.