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Micro-Doppler methods of detecting and classifying small UAVs are limited in range due to the weak radar returns from their plastic propellers. Smaller windows of data instead of longer windows are used for detection as stationarity assumptions often fail for longer windows. Traditional non-parametric methods may be inadequate as they have limited spectral resolution with smaller windows and may provide false detection when radar returns are weak. A rotary drone detector using the number of Helicopter Rotation Modulation (HERM) lines is considered in this paper. Two parametric methods for estimating the number of HERM lines, Minimum Description Length (MDL) and Akaike Information Criterion (AIC), are considered for detection purposes. Experiments using real data acquired using a micro-helicopter drone and a commercial ultra-wide band radar reveal that MDL performs significantly better than AIC and the traditional Fourier-based non-parametric estimation methods.

Energy Internet is a hot spot of research and practice in the field of energy at home and abroad. DC power distribution technology has the characteristics of bidirectional controllable power flow, convenient access to distributed resources, improved power quality, transmission capacity and reliability of power supply, and reduced system loss, which has a wide application prospect in energy Internet. The safety and reliability of ubiquitous distributed generation (DG) and multi load access to DC distribution network is an important problem to be studied and solved in the planning and operation of energy Internet. In this paper, the different ways and operation characteristics of AC-DG and DC-DG connected to DC distribution network are analyzed, in which AC-DG is connected through voltage source inverter, and DC-DG is connected through full bridge DC / DC converter. Based on PSCAD / EMTDC, and taken Shenzhen flexible DC distribution network demonstration project as an example, the dynamic operation characteristics of DGs under different modes of connecting to the DC distribution network are analyzed and verified.

Energy Internet is a hot spot of research and practice in the field of energy at home and abroad. DC power distribution technology is an important element of energy Internet. How to plan the type and capacity of energy storage system (ESS) is a problem worthy of attention when designing the optimal energy conversion path in the energy Internet, especially in the DC distribution network. The proper type and capacity of ESS can effectively suppress DC voltage flicker and improve the system operation stability and fault crossing ability. In this paper, the hybrid energy storage scheme of energy storage battery and super capacitor is adopted in DC distribution network, and the discrete Fourier spectrum analysis of power demand sample data is carried out to obtain the basic power in low frequency and fluctuating power in high frequency. The energy storage battery with slow dynamic response speed is used to match the power demand of low-frequency segment, and the super capacitor with slow dynamic response speed is used to match the power demand of high-frequency segment. The influence index of SOC over limit times of energy storage system is introduced to seek the critical value of ESS capacity planning. Finally, the proposed hybrid energy storage planning method is verified by the case studying.

Detecting and identifying drones is of great interest due to the proliferation of highly manoeuverable drones with on-board sensors of increasing sensing capabilities. In this paper, we investigate the use of radars for tackling this problem. In particular, we focus on the problem of detecting rotary drones and distinguishing between single-propeller and multi-propeller drones using a micro-Doppler analysis. Two different radars were used, an ultra wideband (UWB) continuous wave (CW) C-band radar and an automotive frequency modulated continuous wave (FMCW) W-band radar, to collect micro-Doppler signatures of the drones. By taking a closer look at HElicopter Rotor Modulation (HERM) lines, the spool and chopping lines are identified for the first time in the context of drones to determine the number of propeller blades. Furthermore, a new multi-frequency analysis method using HERM lines is developed, which allows the detection of propeller rotation rates (spool and chopping frequencies) of single and multi-propeller drones. Therefore, the presented method is a promising technique to aid in the classification of drones.

Developing renewable energy generation such as wind power and photovoltaics is an effective way to cope with energy shortage and environmental problems. The virtual power plant (VPP) realizes the grid-connected operation of intermittent distributed renewable energy by aggregating multiple types of distributed energy resources. In order to achieve the energy optimization problem of the VPP, an optimization method of VPP considering coordination and interaction of source-load-storage is proposed in this paper. First, models of components in the VPP are established. Next, an energy optimization model of the VPP considering coordination and interaction of source-load-storage is constructed. Finally, a case is studied to verify the correctness and effectiveness of the method. The results show that the coordinated consideration of distributed generation, energy storage and demand response loads contributes to reducing the operating costs and carbon emissions of the VPP.

Power demand is constant increasing, so power networks are push to the operation limits. Traditional presentation of SCADA/EMS HMI(Human-Machine-Interface) is not more suitable to this situation. Various technology such as AI base alarming, dynamic coloring, contour, map based diagrams, new presentation methods are purposed. New method for indication and measurement alarm processing, measurement presentation, topology presentation, risk assessment presentation, KPI presentation, map based presentation are implemented. Through these presentation techniques, the operators can comprehend the system information easily and more accurate, then more proper action can be promptly taken to ensure the power networks operate more safely and more economically.