| In recent years,with the intensification of global climate change,the frequent occurrence of various natural disasters has always reminded people of the importance of environmental protection,the use of non-renewable resources often produces various kinds of pollution to the environment,the Chinese government has actively invested in various new energy industries to deal with this problem,among which photovoltaic power generation is highly favored due to its abundant solar energy reserves and its own clean and environmentally friendly characteristics.Along with the steady development of new energy vehicles in China in recent years,the construction of electric vehicle charging stations has gradually become popular,among which unattended photovoltaic charging stations are a good complement to the charging of new energy vehicles in remote areas,such power stations are located in remote areas,where the environment is harsh and inconvenient to maintain,and power cable failures often have a negative impact on the operation of the entire power station,so this paper uses extended Therefore,this paper uses the extended spectrum time domain detection method to study the problem of cable fault detection,in order to accurately determine whether a fault has occurred in the cable and the location of the fault point.This paper accomplishes the following tasks:1.In order to solve the problem of insufficient accuracy caused by the noise and transmission voltage in the cable during the extended spectrum time-domain reflection detection,a singular spectrum decomposition method is used to process the mixed signals collected from the cable,and the signal-to-noise ratio is improved by decomposing and reconstructing to reduce the noise components in the signal.Then,the joint weighted generalized correlation algorithm is used to estimate the time delay of the transmitting signal and the noise reduction processed mixed signal,and it can be verified in the-5dB Gaussian noise environment.and SCOT generalized mutual correlation method has certain advantages.2.For the previous proposed method,it is difficult to meet the efficiency requirements of cable inspection in unattended photovoltaic power plants due to the large amount of calculations,and a cable fault detection device is implemented on the FPGA hardware with basic correlation operation as the time delay estimation method,which can meet the requirements of test signal transmission,reception and local time delay estimation operation to derive the fault type and approximate distance information.After the initial location of the faulted cable,the collected information is sent to the host computer for further processing through the singular spectrum decomposition combined with the generalized correlation method.The hardware platform is verified to be able to determine the cable fault type and distance information. |
