Concentrated Solar Power (CSP) has gradually become an emerging development direction in the clean energy area because of its high energy efficiency, renewable and abundant nature. Thermal storage devices are used to regulate the power generation characteristics of CSP plants, and a rational configuration of thermal storage capacity can effectively reduce the system's carbon footprint. Considering the generation cost of thermal power generators, operation and maintenance cost of CSP plants, and system spinning reserve cost, a low-carbon economic dispatch scheme for power systems including CSP plants that takes carbon trading into account is proposed in this paper. On this basis, a thermal storage capacity allocation method for CSP plants is proposed, taking into account the thermal storage cost and dispatching cost. Additionally, simulation verification is performed on IEEE 30 network, and the findings demonstrate that the designed thermal storage capacity configuration strategy effectively reduces carbon emissions and overall system costs.
In recent years, the composite insulators of high-voltage transmission lines in the coastal areas of China have repeatedly experienced the phenomenon of decay-like fracture which is different from the usual mechanical fracture. A detection method is urgently needed to detect this defect of insulators. Therefore, the vibration detection is studied. To investigate the impact of decay-like defects on the vibration mode of composite insulator rod, a 110kV composite insulator simulation model with decay-like defects was built using analysis software to analyze the change of the characteristic frequency. Firstly, the principle of vibration detection for composite insulators is analyzed. Then, the defect-free model and decay-like model of composite insulator rods are established by applying actual measurement parameters. The simulation analysis of insulators with defect-free FRP core, defect along radial development and defect along axial development is conducted respectively. The simulation results show that compared with the defect-free rod, the characteristic frequencies of the insulator rod with decay-like defects are reduced. In composite insulators with decay-like defects, the more serious the degree of this defect, the lower the characteristic frequency, which is of great significance to detect the decay-like defects of composite insulators.
In order to study the frequency domain characteristics of the loss current in the leakage current of XLPE cable when there are conductor spikes in the insulation layer, firstly, the conductivity characteristics of XLPE material are simulated and analyzed theoretically. Then a simulation model of XLPE conductor spike is established, and the loss current under different tip radius of curvature and spike plate spacing is simulated and analyzed. A confirmatory experiment is carried out under the conditions of tip radius of curvature 30 and spike plate spacing 3 mm. The computational and experimental results demonstrate that the conductivity properties of insulation materials move into the non-ohmic area when there is a conductor spike defect in the XLPE insulation due to the abrupt increase in the local electric field intensity. The waveform of the loss current is distorted, and the higher-order harmonic components are superimposed. There will be obvious third-order and fifth-order harmonic components. The greater the severity of the defect, the greater the harmonic distortion rate of the loss current.
After the ship docks, the shore power system is used more and more frequently, and the uninterrupted power switching strategy is an important issue. In this paper, combined with the characteristics of the ship-shore grid connection, the grid connection process is optimized when the shore power system does not need a black start, and a voltage source converter control strategy based on current vector control is proposed. Amplitude-frequency outer loop control is added to realize system frequency and elegant tracking control, and support island operation. This paper also deduces the input and output control model of the ship-shore interconnection system, and analyzes the system stability in the control strategy, the tracking characteristics of frequency and voltage, and the anti-interference characteristics of the load current. Finally, a simulation experiment platform is built, and the experimental results show the effectiveness of the proposed uninterruptible switching control strategy.
Power distribution equipment is vulnerable to comprehensive impacts such as natural disasters, human activities, tree barriers, and bird damage during operation. However, the volume of power distribution equipment is large while the online monitoring coverage is low. Inspection is one of the main means to obtain its operating status. In order to make full use of patrol text, enhance the operation stability of power distribution equipment, and reduce operation and maintenance costs, a classification method for cable inspection texts based on word embedding and recurrent convolutional neural network is proposed to identify the environmental risks of cables. First, the inspection text was preprocessed by eliminating the punctuation marks and annotations, with the word vector model pre-trained. Then the recurrent convolutional neural network (RCNN) model was built and the text was embedded into feature vector with the pre-trained word vector model, by which the RCNN model was trained. Finally, the classification model were evaluated by F1 value and accuracy rate. The example analysis shows that the F1 value of circuit patrol text classification and recognition evaluation index is as high as 0.8771, which indicates that the word embedding and circular convolutional neural network model proposed in this paper can effectively extract the local features and global features of patrol text, achieve accurate risk level classification, and provide algorithm support for the distribution cable Big data analysis system.
