Design of main ring dipole power supply for Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring

The main dipole power supply is the pivotal device of the Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring (HIRFL-CSR) project and is the most technically demanding source. A special topology and control method has been used in the power supply. This paper firstly introduces the main circuit topology, which includes a silicon controlled rectifier and a parallel switching-mode rectifier. The topology is adopted to realize the peak output power of 3.15 MW (3 kA, 1.45 kV) and pulse-mode working state. Then it presents and discusses the control method and double reference setting system of the power supply, which are used to fulfill the strict requirements especially for the tracking error (less than ±2×10-4). Finally, it introduces the process of commissioning and the upgrading o