Commercially available light-weight unmanned aerial vehicles (UAVs) present a challenge for public safety, e.g. espionage, transporting dangerous goods or devices. Therefore, countermeasures are necessary. Usually, detection of UAVs is a first step. Along many other modalities, acoustic detection seems promising. Recent publications show interesting results by using machine and deep learning methods. The acoustic detection of UAVs appears to be particularly difficult in adverse situations, such as in heavy wind noise or in the presence of construction noise. In this contribution, the typical feature set is extended to increase separation of background noise and the UAV signature noise. The decision algorithm utilized is support vector machine (SVM) classification. The classification is based on an extended training dataset labeled to support binary classification. The proposed method is evaluated in comparison to previously published algorithms, on the basis of a dataset recorded from different acoustic environments, including unknown UAV types. The results show an improvement over existing methods, especially in terms of false-positive detection rate. For a first step into real-time embedded systems a recursive feature elimination method is applied to reduce the model dimensionality. The results indicate only a slight decreases in detection performance.
High temperature superconducting (HTS) generators could enable a lightweight and cost-effective direct drive (DD) wind turbines with large power ratings. The EU-funded EcoSwing project successfully demonstrated the world's first full-scale MW-class HTS generator on a commercial DD wind turbine. This paper focuses on the commissioning of the EcoSwing HTS generator on the wind turbine. The commissioning campaigns, including the rotor cool-down, excitation of the HTS field winding, and the power production of the generator, are presented in the paper. In the testing period, the generator was grid-connected for more than 650 hours and accumulatively produced more than 600 MWh to the grid. The target output power of the 3 MW class was reached. Throughout the real-life testing on the wind turbine, the generator performed well from the electromagnetic, thermal, and mechanical perspectives. Moreover, the generator even sustained three sudden short circuits in the converter system. The work reported has shown that HTS generators are technologically feasible for wind turbine applications, and the technology readiness level of HTS wind turbine generators has been improved to 6~7 for the first time.
The different measures for voltage and frequency maintenance as well as black start capability, which are mainly provided by conventional power plants today, are a matter of discussion in this paper. The ongoing energy transition, together with a politically decided phase out of nuclear and coal fired power plants in Germany, leads to a lack of availability of ancillary services which has to be filled up with distributed generators (DG). Especially in critical network situations and during power system restoration, there is a need for direct assignable ancillary services by the network operator. Within the research project “SysAnDUk”, methods for creating power plant characteristics to provide ancillary services for the network and system operation with a large number of DG shall be developed. Two ideas are pursued: the aggregation of numerous of wind power plants (WPP) connected to the high voltage grid considering the network topology, and the aggregation of a multitude of small photovoltaic units connected to the low voltage and medium voltage grid based on defined geographical areas. Appropriate probabilistic forecasts are implemented in both concepts to display available active power with different safety margins. In an exemplarily case study it is shown by dynamic simulation, that a WPP can provide service to maintain the voltage within predefined limits by means of coordinated reactive power feed-in acc. to a Q(U)-characteristic curve and by voltage control during early stage of system restoration starting in the high voltage grid. Both require online setpoint provision from the network operator. This provides new options for necessary compensation of unloaded lines.