Multi-channel DMA Based Design of Voltage Monitoring Using Synchronous Frequency Trace-Sampling Technique

In order to eliminate the influence of frequency change on real-time voltage acquisition, a low-cost solution of voltage monitoring was proposed using the multi-channel DMA synchronous frequency trace-sampling technique. In-chip resources of the designed voltage monitor were fully utilized in hardware design to reduce external devices. The MQX RTOS was used to perform the functional tasks flexibly and efficiently; especially the Ethernet communication applications and USB device connection were realized using its TCP/IP protocol stack and USB driver. In addition, to ensure the safety of electrical records, data statistics and alarm information management were also implemented through the management of the storage in FLASH. The test results show that the voltage monitor designed in this paper has the advantages of accurate measurement, strong resistance to frequency interference and low cost, and can be widely applied in the field of voltage monitoring in distribution networks.