Research On Load Characteristic And High Frequency Discharge Power Supplies Of DBD Type Ozonizer

Power Electronic is new type subject which syncretize electric power, electronics and control, and its applications have come into many domains such as industries, agricultures, national defenses and traffics. Beginning with its application of producing ozone, the load characteristics and the discharge power-supplies of the dielectric barrier discharge(DBD) type ozonizer have been deeply analyzed and studied in the paper.Firstly, the physical mechanism and characteristic of producing ozone by DBD have been expatiated. The study actuality and developed directions have been summarized in two aspects as the ozonizer and the discharge power supplies. According to the problems on studying the discharge power supply, the feasibility and necessary have been proposed in the paper that devising and facture the high frequency discharge power supplies for ozonizer by modern power electronic technique on the basis of studying the load characteristic of the DBD type ozonizer deeply.Secondly, the theoretical analyses and experimental studies of the load characteristic of the DBD type ozonizer have been studied deeply in the paper. Starting from the physical mechanism and characteristic of DBD and assuming the load voltage is a sine waveform, the load current is a sine waveform or the load current is a square waveform respectively, the load characteristic of the ozonizer have been analyzed detailed including the beginning time of the discharge, the critical condition of discharging, the relations of the load voltage and current in the courses of no-discharge and discharge, the load average equivalent capacitance and the load power consume, etc. All these proposed theoretical basis to study and devise the discharge power supplies for ozonizer.A method of measuring the load parameters and calculating the load power consume in discharge by capacitance is also been introduced. The experiments have been made on the load, the experimental results have been analyzed detailed and 3-direction curve of the load characteristic has been made. The experimental results validated the validity of theoretical analyses and proposed a foundation to devising and studying the high frequency discharge power supplies for ozonizer.Thought about the higher frequency is propitious to intensify the ozone synthe-sization and the capacitive characteristic of the ozonizer, the voltage sources inverter is chosen for the main circuit of the discharge power supply in the paper and the load forms series resonant circuit with the inductance of the transformer in high frequency. According to the load characteristic, the traits of the discharge power supplies with different control strategies are analyzed and compared. For the high frequency discharge power supplies based on capacitive PWM mode which phase-locked of thecurrent passing zero has the merits of small variational range of the working frequency and low switching losses, so the viewpoint that it is more suitable for the load is proposed in the paper, and the discharge power supplies for the ozonizer with the control strategies based on capacitive PWM mode which phase-locked of the current passing zero and based on resonant PWM mode have been deeply analyzed and studied from the aspects of the realizations of the control strategies, the course of the current commutated in the main circuit, the circuits and experiments .Finally, the summarization has been made and expectation of the work has been given in the paper.