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A high reliable and low noise frequency synthesizer was designed and manufactured by 0.18um SiGe BiCMOS process. The innovation of this paper is to use HBT with better 1 / f noise performance to replace MOS transistor to obtain better noise performance. The frequency synthesizer circuit is capable of producing 1.7GHz-2.3ghz RF output signal (one of the VCO output bands); The operating frequency of the frequency synthesizer is 800MHZ-5GHZ. The normalized phase noise of the frequency synthesizer reaches −230 dBc /Hz.

With growing popularity of lithium batteries in power systems, remaining useful life prediction of batteries is gaining importance. A long-term remaining useful life prediction approach for lithium-ion batteries based on grey theory is presented in this paper. Firstly, an optimized discrete grey model is used to track the battery overall degradation trend. Then, Markov chain is implemented to compensate the error of grey model, which is mainly sourced from fluctuations of curve caused by capacity regeneration. Finally, relevance vector regression is utilized to provide the final remaining useful life value and its probability. The universality and accuracy of this approach are validated with battery data under different discharge rates and temperatures.

In order to allow efficient planning of electric power system, the reliable prediction of photovoltaic power generation is very important. This paper proposes a new solar power probabilistic forecasting method based on dynamic weighting method, K-Nearest Neighbor (KNN) algorithm and quantile regression neural network (QRNN). Firstly, a new dynamic weighting method is used to tune the optimal weights of meteorological factors dynamically. Then based on the optimal weighted Euclidean distance metric method, KNN algorithm is used to find the similar examples more accurately. Finally, QRNN model is established to obtain different quantiles and approximately estimate the probability distribution of solar power output. The data from IEEE Working Group on Energy Forecasting is used to valid ate the effectiveness of proposed method and the experimental results show that the proposed model has reliable and accurate prediction ability.

High frequency is the development trend of switching power supplies to achieve miniaturization density of switching power supplies. However, the increase in frequency makes the leakage inductance parameter of the transformer in the switching power supply more and more important to the performance of the circuit. In this paper, the leakage inductance and winding loss of high frequency transformer in LLC resonant converter are analyzed in detail. An optimized design scheme of high frequency transformer based on winding structure is introduced, which can effectively reduce the leakage inductance and winding losses of high frequency transformer, and improve stability and efficiency of the transformer resonant converter. Finite-element analysis simulation validate the design scheme.

LLC resonant converter typically works in Pulse Frequency Modulation (PFM) mode. The output voltage can be adjusted by adjusting the switching frequency of the converter. In order to meet wide voltage variation and various load conditions, the switching frequency of LLC converter must be changed in a wide range, which brings great difficulties to the design of high frequency transformer and the selection of power devices. Based on the analysis of the relationship between dead-time and operating characteristics of LLC resonant converter, this paper establishes the mathematical relationship between resonant tank gain and dead-time of LLC resonant converter, and makes theoretical analysis and experimental verification. The results show that without increasing the gain of the converter, increasing the dead-time appropriately can reduce the switching frequency range of the converter, thus reducing the design difficulty and the switching loss of the converter.

Polarization diversity can improve channel capacity and reduce signal fading. This paper proposed a dual-polarized monopole antenna with simple structure for polarization diversity system. The proposed antenna was composed of inverted-F antenna and inverted-L antenna, which were orthogonally mounted in space. The planar mental plate was used to obtain the unidirectional patterns. The frequency range of discussed antenna was from 2.35GHz to 2.55GHz. The antenna structure was designed and simulated by full-wave electromagnetic simulation technology. The designed dual-polarized monopole antenna had an analog voltage standing wave ratio (VSWR) of less than 2, and the relative frequency band was about 8.16%. The axial ratio (AR) of each polarization port at the boresight for the designed antenna was higher than 20dB. For each port, the wide beam was achieved, which was suitable for the array antenna application. What’s more, the antenna miniaturization was also realized. The proposed dual polarization antenna had simple structure, low cost and was suitable for engineering application.

With the development of power electronics technology, compared with AC and DC power distribution network, the energy router has tremendous potential for its obvious advantage and make a significant contribution to the energy internet. Firstly the key devices of the energy router is discussed and the network framework of the small energy router in user layer is proposed. Then the research status of isolated bidirectional DC/DC converter(IBDC) is reviewed systematically. Subsequently the circuit topology of dual-active-bridge(DAB) and resonant full-bridge are analyzed in detail, the corresponding control strategies are studied and the characteristics of above mentioned converters are also summarized. Finally the key issues of the power electronic transformer(PET) or solid state transformer(SST) to be solved urgently are also pointed for energy router application. Conclusions will provide essential theoretical and practical basis for industry application of future energy router.

we focus on the distance in fuzzy metric space. The general distance of general fuzzy sets are introduced. Some properties of Chebyshev distance of general fuzzy sets and normalized Hamming distance of general fuzzy sets are studied. Furthermore, some special metrics of two fuzzy interval valued sets are introduced. We give the source of the two forms of moore distance. Finaly, in Hausdorff metric space, the normalized Hamming distance are investigated. This research will provide the necessary tools for approximate reasoning.

Due to the test costs and test organization, it is difficult to make a large number of tests, the precision of assessment can be improved by using unit information when estimating the reliability of electronic components. When the data are zero-failure, the precision can be improved obviously by using Bayes method with reducing the number of samplings. This paper presents that during the process of test, the accuracy of the quality assessment for electronic devices can be improved by using Bayes method with full use of prior information.

Testing and evaluation of supportability is summarized on equipment. The related concepts and research of testing and evaluation of supportability are summarized, and the key technologies are analyzed. Finally, the development of the test and evaluation of supportability on our military is summarized and prospected.

Full-Potential Linearized Augmented Plane Wave plus local orbital method (FPLAPW +lo) calculations were performed for CeFe 4 P 12 in the filled skutterudite in order to investigate the optical properties and to show the origin of the different optical transitions. It is found that the CeFe 4 P 12 compound has a indirect band gap: 413.41meV. Then the contributions of the different transition peaks are analyzed from the imaginary part of the dielectric function. In contrast to recent experimental expectations, our calculations are in good agreement with experimental reflectivity spectra. Furthermore, the different optical properties have been investigated. We have studied the absorption coefficient, the electron energy loss function, the refractive index, and the extinction coefficient.

A kind of small scale solar irrigation control system based on FPGA is realized in this paper. The design which is composed of variable step MPPT algorithm, multiple SPWM output, motor control and the corresponding display module can drive the motor through energy storage devices and power converters. The language of verilog is used and the software of modelsim is adopted to verify the design.

A novel approach of path planning for unmanned aerial vehicle(UAV) is presented based on immune genetic algorithm(IGA) with elitist. IGA introduces immune operator and concentration mechanism which improve the inherent defects of premature and slow convergence speed existing in genetic algorithm (GA). Simulation results show that an ideal flight path can be more quickly searched using IGA, under conditions of meeting the requirements for UAV and the given constraints. Correctness and effectiveness of IGA are verified.

This paper is concerned with the management of the large amount of information of large-scale PV systems, a new approach that can monitor the status and detect faults for large-scale PV systems is derived. We first design a new type of photovoltaic (PV) arrays connection, and establish its framework for fault diagnosis. Then , based on the so called "data fusion" technique, we merge the difference information between the measured value and the theoretical value, the measured value and the average value by side respectively, including the electrical information (voltage and current), solar illumination, environmental temperature and the speed of win. A PV cell is used to verify the effectiveness of our proposed method. It shows that our method has high accuracy and reliability for the fault diagnosis system.

In this paper, an adaptive fuzzy MPPT controller is designed with FPGA, the design of fuzzy controller and adaptive control theory is described in detail, and it is discussed that how to implement adaptive fuzzy MPPT control with FPGA, and finally The solar storage control system is built with the controller, the experiment proved that the controller using this method can adjust the parameter according to the change of the external condition, with fast search optimum ability to make the system working at the max power point steadily, lays the foundation for SoC design of PV system.

After discussing analysis of existing photovoltaic system maximum power point tracking (MPPT) control method, FPGA-based fuzzy MPPT control algorithm is proposed, this method is simple, reliable, and can automatically adjusts with the changes of external environment. Its fast optimization capability makes the system stable at the maximum power point. The MATLAB simulation of fuzzy control proves its fast response and steady-state performance achieve expectation. And fuzzy MPPT algorithm is designed with verilog language and downloaded to the chip. Experiments proved the effectiveness of this method of photovoltaic power generation system. It lays the foundation for SoC(System on a Chip) control.

As the complicated structure of the PV generation systems and variety of application environments, the mismatch and hot spot phenomena caused by partial shade or non-uniform illumination not only heavily affect the output characteristics of photovoltaic arrays, but also create safety and reliability problems. This paper proposes a self-adaptive reconfiguration method based on fuzzy control, introduces how to apply it to the photovoltaic power generation systems, and explains why fuzzy control based on the shading degree of PV arrays can quickly respond to the changes of external environments. The experimental results show when the partial shade phenomenon occurs, changing the connections of the solar PV submodules using switching matrix can quickly reduce the loss of output power.

Partially shaded conditions are common in all kinds of PV systems. The mismatch phenomenon of a Solar PV array, such as partial shade, not only affects the power generated by solar system, but also leads to safety and reliability problems. This paper proposes a new shading degree model-based self-adaptive reconfiguration method to reduce the effect of shadows on solar arrays. A switching matrix dynamically connects a solar adaptive bank to a fixed part of a solar photovoltaic array based on the shading degree model-based control algorithm to increase the power output of the solar PV array.

Partially shaded conditions are common in all kinds of PV systems. The mismatch phenomenon not only affects the power generated by solar system, but also leads to security problem. Still, under partially shaded conditions, the P-V curve of PV arrays will have the characteristics of multi-summit, which makes the maximum power point tracking very difficult to accomplish. In this paper, the PSO algorithm is applied to the MPPT control algorithm in two different PV structure. Based on establishing the multi-peak model of the PV array under partially shaded condition, the multi-peak MPPT algorithm is designed. Through the introduction of modular structure, the distributed MPPT algorithm is presented. The effectiveness of the algorithm and the advantages and disadvantages of two different algorithms are examined using the MATLAB. At last, the hardware circuit of the control system with man-made partially shaded condition is constructed. The effectiveness and preciseness of the MPPT system is proved by the results of the experiments.

As to detecting the occurrence of Hot Spot, this paper presents a new type of photovoltaic (PV) arrays connection: CTCT structure (complex-total-cross-tied array). In the array of CTCT-type PV cells, by adding a certain number of current sensors and comparing the current, we can find the location of PV cells that have Hot Spot. This paper derives a formula to demonstrate the relationship between the total number of solar panels in parallel, the resolution and the total number of current sensors. We can detect the precise location of PV cells that have Hot Spot by using current sensors as few as possible.