Development Of High Power Magnetron DC Power Supply

This paper presents a design of high power DC power supply for magnetron. The magnetron is an electric vacuum device to generating microwave energy. The electrons in the tube interact with the high frequency electromagnetic field under the control of the perpendicular constant magnetic field and electric field, converting the energy of the constant electric field into microwave energy. At present, the reliability problem of low-power magnetron application power has been basically solved. The complexity of the magnetron load characteristics and harmonic interference and other reasons resulting in outstanding contradictions of high-power magnetron application power’security. As for the field of magnetron applications technology, the first need is to develop a safe and reliable high-power DC power supply. The main contents of this paper are as follows:The magnetron are discussed from these aspects: structure and electrical parameters to express load characteristics. Inverter is the core of high-power. In order to reduce the switching loss and harmonic interference, and achieve soft-switching, the paper compared resonant converters with different working and wiring modes. And selected LCC series-parallel resonant converter, taking leakage inductance and the equivalent distributed capacitance as a part of the LCC resonant converter’s main resonant components. While the main extension structure of the resonant circuit is given,the two working states of the resonant current intermittent mode are analyzed in detail,and deduced by mathematical modeling to further stating the characteristics of the resonant circuit. The related waveforms of the resonant converter are simulated and demonstrated the correctness of the design and parameter selection.In this paper, the main circuit and the control circuit of the high power DC power supply are designed. The three-phase AC power incorporated by distributed generators,flowing through the rectifier circuit, inverting circuit, the high frequency transformer and the high voltage silicon reactor diode, getting DC superimposed pulsed HV and send to the magnetron anode and it make a brief explanation to magnetron cathode power. The control circuit includes the main power supply circuit, the driving circuit,the analog and digital acquisition and conditioning circuit,including the part of temperature detection acquisition circuit has carried on the simulation analysis to prove the correction of design. The design parameters of the chip are described in detail, and the function and principle of the circuit are detailed analysis combining with the circuit diagram.The software process of the power supply is designed. We give and explain the flow chart of the response, including the main program flow of the power system, the PWM wave generation, the acquisition of the analog, the overcurrent protection and the transformer bias magnetism detection.