Research On Analysis And Protection Technology For Transient Electromagnetic Interference In Electro-optical System

With the development of electro-optical technology in China, high power, high current electro-optical systems are widely used in military and civil areas, and gradually become the representative of high-tech equipment in the new era. This paper is in order to carry out research on the electro-optical system with the high power laser as core component. The laser is a kind of the high power pulse type gas laser, which is working at high voltage, high current environment. On the basis of analysis spark switch, main circuit of laser and the light exit to space radiation strong transient electromagnetic interference, a transient electromagnetic interference simulator has been developed. The protection technology of sensitive equipment such as the LCD control system has been researched. And the goal of transient electromagnetic interference’s analysis and protection can be achieved. The results of the study have important guidance and reference value of the development and integration of equipment in high power pulse transient electromagnetic environment. The Paper’s main research works are as follows:This paper analyzes and tests the sources, sensitive equipment and disturbance path of electromagnetic interference in the electro-optical system. The test and prediction methods based on transient electromagnetic radiation sensitivity have been carried out. A synthesis of dipoles of field radiation within the laser electric field has been presented and the method has been proved to be rational to guide the design of electromagnetic interference protection.The method of using transient electromagnetic interference simulator to verify the effectiveness of system interference protective measures has been proposed. And a transient electromagnetic interference simulator has been designed. The simulator consists of three parts: discharge trigger signal source, high voltage capacitor charging power supply and discharge actuator. The technology of series resonance and voltage-current double closed loop control has been used to ensure the smooth of voltage and current in full cycle charging process. Test shows that the characteristics of output transient electromagnetic interference and the laser are basically the same.Based on the research of EMC design in electro-optical system, connecting cables, PCB assemblies, transmission line, laying path, filtering, grounding, the research of electromagnetic shielding box design has been focused on. CST MWS has been presented in this paper with the measured data regression method for modeling and design the shielding box. The statistics and analysis of aperture’s size, shape and number effect on the shielding box performance have been done. The testing proved that the shielding box can better protect against transient electromagnetic interference.The protection measures against many electromagnetic sensitive parts of the electro-optical system have been designed. Based on the verification process of the system protection measures by using the simulator, the system’s integration has been achieved, and the whole system’s EMC performance requirements have been satisfied.