Research On The Power Supply Of DBD Type Ozone Generator Under The Trapezoidal Excitation

Because of Ozone unique physical properties, Ozone has been widely used in many fields, for example the daily life, the industrial production and health care.There are many methods to generate ozone, such as electro-analysis method, ultraviolet radiate on irradiation method, radiation method, DBD (Dielectric Barrier Discharge) method. In these methods, Because of its unique advantages,DBD method has been adopted widely in modern scientific research workers,Now, the power supply of DBD type ozone generator adopts the series-parallel resonant inverter power supply, By adjusting the excitation amplitude and frequency of the ozone generator sine or quasi sinusoidal to regulate the discharge power so as to adjust the output of the ozone generator. But the efficiency of the discharge type DBD ozone generator not only relating with the generator terminal voltage amplitude but also relating with the time ratio of the charging stage time than discharging stage time. Namely the ozone generator can get higher discharge efficiency depending on the less charging time and maintaining the discharge voltage in high voltage value(the value depends on the pressure of discharge tube).So, from this point of view, using the sine wave as the excitation for DBD type ozone generator source is not the most driving source. In order to solve this problem, the DBD type ozone generator power supply was studied and discussed, and mainly from seeking the new topology to get the trapezoidal excitation, the regulation characteristics of electrical variables in the power system, realizing the function of hardware circuit and the digital control in the whole process. This paper is divided into the following sections:(1)In order to meet the design requirements of subsequent power supply, the equivalent model of the DBD type ozone generator and the measurement of dielectric parameters of the DBD type ozone generator are described. Based on the study of the equivalent model at home and abroad, we set up a continuous equivalent model which can accurately predict the load characteristics of DBD type ozone generator. Namely the ozone generator is equivalent to the capacitor and nonlinear resistor. In order to get the parameters of DBD type ozone generator, this paper also analysis the measurement method of Lissajous that is currently widely the measurement of the dielectric parameters. To obtain the accurate load parameters, we adopt the method of multiple sets of measurements to calculate the key points of the DBD type ozone generator.(2)With the time-space simulation model of DBD (Dielectric Barrier Discharge:DBD) circuit, the discharge efficiency of DBD circuit under different excitation waveform (sinusoidal excitation waveform, square excitation waveform, trapezoidal excitation waveform, triangle excitation waveform) is made. By comparison, trapezoidal excitation waveform is a very suitable for DBD circuit. Based on the synthesis of ideas of alternating trapezoidal incentives and power adjustment requirements of power supply for DBD circuit, double-frequency resonant inverter power supply topology for the ozone generator which can produce the alternating trapezoidal wave on the DBD load is designed.(3)Based on the topology, the drive timing for the new topology is designed, which ensure the DBD type ozone generator on the incentives for alternating trapezoidal excitation source and can realize the discharge power. The equivalent performance record of power supply under different modal are analyzed. The working mode of the new topology is achieved and the constraint equations of working mode are deduced. The regulation characteristics of electrical variables in the power system are analyzed.(4)The control of power supply adopts the DSP-TMS320F2812, using that as the control core. The driving waveforms are made by the TMS320F2812 event manager to produce PWM wave and the dead zone regulating circuit. At the same time all of the hardware circuit diagrams are given. The parameters design and the device models selection are derived in the EMI filter circuit, single phase uncontrolled rectifier circuit, LC filter circuit, and double-frequency inverter.(5) To validate the correctness of the theoretical analysis which the power supply scheme of DBD ozone generator under the trapezoidal excitation. Based on the hardware circuit of power system, we set up the simulation model and the experimental platform. The simulation waveforms and experimental waveforms are given. In these waveforms, we can get that the simulation waveforms and waveforms are closed to theoretical analysis, so as to verify the correctness and feasibility of the power supply system.