| Improving indoor air quality is an important research topic in the environmental field.Electrocoagulation technology is an important means to reduce the concentration of fine particles.At present,there are many domestic and foreign research reports on the analysis of particle coagulation characteristics under the action of low-frequency pulse power.Experiments have found that under the high-frequency alternating electric field,particles will have a resonance coagulation and enrichment area,and the coagulation effect is better in this area.Therefore,it is of great significance to study the resonance coagulation characteristics of fine particles by the high-frequency alternating pulse electric field.At present,the commonly used test platform cannot meet the needs of high-frequency resonance testing.Based on this,this paper designs a high-frequency resonance coagulation measurement and control system for space particles.The thesis first analyzes the mechanism of charged coagulation of particulate matter in detail,and proposes a resonance coagulation measurement and control method,that is,the charged particulate matter performs high-intensity relative motion under the action of a pulsed electric field to change the driving signal of the modulator.The fundamental frequency makes it the same as the natural frequency of the particles in the resonant cavity,forming a strong resonance.In this state,the particles coalesce sharply.Aiming at this method,a detailed measurement and control system scheme design is carried out,focusing on five parts: resonance control unit,main power supply,auxiliary power supply,system monitoring scheme,and structure scheme.The resonance control unit includes a high-voltage power supply and a highvoltage pulse modulator,and the high-voltage pulse modulator includes a pulse modulator,a driving power supply,and a resonance current detection.In the early stage of the thesis,each part of the system was demonstrated to ensure feasibility.According to the system scheme,implement specific software and hardware for each part.In terms of system hardware,the paper elaborated on the parameter selection of key power supply components,the system implementation of modulators,and the construction of sensors and particle calibration devices.In terms of system software,the paper elaborated on the design of the host computer software based on Lab VIEW,the program framework based on the state machine,the task framework based on the time slice polling method,the multi-channel AD acquisition and communication mechanism based on the state machine,the particle detection software,and the communication Protocol design.Finally,the paper elaborated the system production and realization process in detail.After drawing the schematic diagram,PCB manufacturing and completing the mechanical structure construction,the hardware test is carried out,and the auxiliary power supply,driving power supply,main power supply,high voltage power supply,high voltage pulse modulator and other power modules are debugged.Analyze multiple key waveforms and solve problems encountered during debugging.Finally,a high-voltage power supply with arbitrarily adjustable output voltage amplitude and a high-voltage pulse power supply with arbitrarily adjustable pulse width and frequency are debugged.After the software and hardware are jointly adjusted,the measurement and control system works normally and achieves the expected goal. |
