大功率电磁发射机开关频率精确控制研究

发射频率范围宽,精度高的大功率电磁发射机可以实现对不同深度目标体的探测。提出了使用DSP+FPGA架构来实现发射机发射频点精确性的方案,介绍了大功率电磁发射机的拓扑结构及H型逆变桥的工作原理,并对如何采用DSP控制FPGA实现PWM波形频率、占空比及死区时间的精确控制进行了研究。在此基础上,研制了输出功率为25 kW样机。野外实验结果证明,所设计的大功率电磁发射机可发射频点的精确度高,范围宽,能应用于实际地质勘探中。

Research on accurate emission frequency control of high-power electromagnetic transmitter

The detection of the high-power electromagnetic transmitter, which has a wide frequency range and high accuracy, can be achieved for different depths of the target body. The solution of using DSP FPGA architecture to achieve the accuracy of the transmitter frequency point is proposed in this paper, besides, the topology of the high-power electromagnetic transmitter and the working principle of the H-type inverter are introduced. In addition, how to use DSP to control FPGA to achieve precise control of the PWM waveform frequency, duty cycle and dead time is also be researched. On this basis, an output power of 25kW prototype is developed. The wild experimental results prove that, the high-power electromagnetic transmitter, which is designed in this paper, has a high accuracy and a wide range of RF point, can be used in the actual geological exploration.