Research on Grid Planning of Dual Power Distribution Network Based on Parallel Ant Colony Optimization Algorithm

A distribution network plays an extremely important role in the safe and efficient operation of a power grid.As the core part of a power grid’s operation,a distribution network will have a significant impact on the safety and reliability of residential electricity consumption.it is necessary to actively plan and modify the distribution network’s structure in the power grid,improve the quality of the distribution network,and optimize the planning of the distribution network,so that the network can be fully utilized to meet the needs of electricity consumption.In this paper,a distribution network grid planning algorithm based on the reliability of electricity consumption was completed using ant colony algorithm.For the distribution network structure planning of dual power sources,the parallel ant colony algorithm was used to prove that the premise of parallelism is the interactive process of ant colonies,and the dual power distribution network structure model is established based on the principle of the lowest cost.The artificial ants in the algorithm were compared with real ants in nature,and the basic steps and working principle of the ant colony optimization algorithm was studied with the help of the travelling salesman problem(TSP).Then,the limitations of the ant colony algorithm were analyzed,and an improvement strategy was proposed by using python for digital simulation.The results demonstrated the reliability of model-building and algorithm improvement.

Dynamics of a Dual Power-split Transmission Based on Loaded Tooth Contact Analysis

In order to implement the dynamic characteristic of a dual power-split transmission, a dynamic me- chanics model is built. Firstly, according to the method of theoretical analysis of the tooth contact analysis （TCA） and loaded tooth contact analysis （LTCA）, the actual meshing process of each gear pairs is simulated, and the time-varying mesh stiffness excitations are obtained, which can improve the numerical precision. Second- ly, by using the lumped mass method, the bending-torsional coupling three dimensional dynamic model of the dual power-split transmission is established, and the identical dimensionless equations are deduced by elimina- ting the effect of rigid displacement and the method of dimensional normalization. Finally, by the method of the fourth order Runge-Kutta algorithm with variable step lengths, the responses of this system in a frequency domain and time domain are obtained, and the dynamic load change characteristics of each gear pairs are analyzed. The results show that the establishment, solution and analysis of the system dynamics model could provide a basis for the dynamic design, and have an important significance for the dynamic efficiency analysis and dynamic perform- ance optimization design of the dual power-split transmission.

Dual Power Allocation Optimization Based on Stackelberg Game in Heterogeneous Network with Hybrid Energy Supplies

In heterogeneous network with hybrid energy supplies including green energy and on-grid energy, it is imperative to increase the utilization of green energy as well as to improve the utilities of users and networks. As the difference of hybrid energy source in stability and economy, thus, this paper focuses on the network with hybrid energy source, and design the utility of each user in the hybrid energy source system from the perspective of stability, economy and environment pollution. A dual power allocation algorithm based on Stackelberg game to maximize the utilities of users and networks is proposed. In addition, an iteration method is proposed which enables all players to reach the Stackelberg equilibrium(SE). Simulation results validate that players can reach the SE and the utilities of users and networks can be maximization, and the green energy can be efficiently used.

Dynamic Power Transmission Using Common RF Feeder with Dual Supply

This paper proposes the design concept of a dynamic charging system for electric vehicles using multiple transmitter coils connected to a common radio frequency(RF)feeder driven by a pair of two power supplies.Using a common RF feeder for multiple transmitter coils reduces the power electronic redundancy compared to a conventional system,where each transmitter coil is individually driven by one switched-mode power supply.Currently,wireless charging of electric vehicles is recommended to operate in the frequency range of 85 kHz and beyond.In this frequency range,the signal wavelength is shorter than about 3.5 km.Therefore,a charging pad longer than several hundred meters is subject to the standing wave effect.In such a case,the voltage significantly varies along the RF feeder,resulting in a variation in the received power level when the receiver moves.Specifically,the received power significantly deteriorates when the receiver is nearby a node of the voltage standing wave.In this paper,we employ a pair of two power sources which are electrically separated by an odd-integer number of the quarter wavelength to drive the RF feeder.As a result,the voltage standing wave generated by one power source is complemented by that of the other,leading to stable received power and transmission efficiency at all the receiver’s positions along with the charging pad.Simulation results at the 85 kHz frequency band verify the output power stabilization effect of the proposed design.It is worth noting that the proposed concept can also be applied to simultaneous wireless information and power transfer(SWIPT)for passive radio frequency identification(RFID)tags by raising the operation frequency to higher industrial,scientific and medical(ISM)bands,e.g.,13.56 MHz and employing similar modulation methods as in the current RFID technology.

Two-dimensional numerical study of an atmospheric pressure helium plasma jet with dual-power electrode

In this paper, the characteristics of an atmospheric pressure helium plasma jet generated by a dual-power electrode （DPE） configuration are investigated by using a two-dimensional fluid model. The effect of a needle electrode on the discharge is studied by comparing the results of the DPE configuration with those of the single ring electrode configuration. It is found that the existence of the needle leads to the generation of a helium plasma jet with a higher propagation velocity, higher species density, and larger discharge width. Furthermore, the influences of the needle radius and needle-to-ring discharge gap on the generation of a plasma jet are also studied. The simulation results indicate that the needle electrode has an evident influence on the plasma jet characteristics.

NOVEL COMPOSITE CVT SYSTEMS WITH DIVERGING AND DUAL-MODE CONVERGING POWER FLOW

A new type of composite CVT(continuously variable transmission) systemsfeatured by power flow divergence and dual-mode convergence, capable of improving CVT's efficiencyand power capacity or making AMTs(automated manual transmissions) become continuously variable, isstudied. With specific mechano-mechanical and electromechanical composite CVT systems as detailedexamples, its basic working principles are expatiated. General methods and key points in designingand realizing such systems are also analyzed and discussed.

NONLINEAR CHARACTERIZATION OF CONCURRENT DUAL-BAND RF POWER AMPLIFIERS

In this paper, the synchronous concurrent dual-band RF signal is used to drive the RF Power Amplifier (PA). The nonlinear characterization of a concurrent dual-band RF PA is discussed while two band signals in the dual-band are modulated by CDMA2000 and WCDMA signals. When the two band signals in the dual-band of the PA are modulated with the same signals, it is found that the nonlinearity of the PA can be expressed by any of the two corresponding baseband data. On the other hand, when the two band signals in the dual-band of the PA are modulated with two different signals, the PA nonlinearity cannot be characterized by any of the two corresponding baseband data. In this case, its nonlinearity has to be denoted by a composite signals consisting of the two baseband signals. Consequently, the requirements for the speed of the A/D converter can be largely reduced. The experimental results with CDMA2000 and WCDMA signals demonstrate the speed of the A/D converter required is only 30 M Sample Per Second (SaPS), but it will be at least 70 M SaPS for the conventional method.

SELF-DUAL PERMUTATION CODES OVER FORMAL POWER SERIES RINGS AND FINITE PRINCIPAL IDEAL RINGS

In this paper, we study self-dual permutation codes over formal power series rings and finite principal ideal rings. We first give some results on the torsion codes associated with the linear codes over formal power series rings. These results allow for obtaining some conditions for non-existence of self-dual permutation codes over formal power series rings. Finally, we describe self-dual permutation codes over finite principal ideal rings by examining permutation codes over their component chain rings.

A new type of Wilkinson dual-frequency power divider with symmetrical transmission line stubs

To realize equal power splitting at two arbitrary gigahertz-frequencies, this paper presents a new type of Wilkinson dual frequency power divider, consisting of three-section transmission lines and a series RLC(resistor, inductor and capacitor)circuit. By equating the [ABCD] matrix of the proposed circuit to that of the quarter-wave impedance transformer, coupled with even/odd mode analyses, the design equations of the proposed network are derived. For verification, two dual-frequency power dividers with dual-band operating frequencies at 0.6 GHz and 3.0 GHz, and 3.8 GHz and 10 GHz respectively are designed and simulated. Simulation results show that the dual-band ratio of the proposed power divider can be as large as 5. Comparisons of the simulation results at X-band and S-band with different power dividers indicate that the proposed dual-band power divider performs better under the scenario of the upper operating frequency extending to X-band.

具有非理想气体工质的内可逆Dual循环最优性能

基于有限时间热力学理论和前人建立的内可逆Dual循环模型,本文进一步考虑非理想气体工质比热模型,对循环的性能进行了研究,推导得到了循环功率和效率的基本优化关系,通过数值计算分析了传热损失系数(B)、预胀比(ρ)、单原子气体自由度(d)和循环最大温比(τ)对循环特性的影响,比较了不同比热模型条件下循环的性能差异.结果表明:随着τ和d增加,循环最大功率(P_(max))、最大效率(η_(max))、最大功率时对应的效率(ηP_(max))、最大功率和最大效率时对应的压缩比(γP)和(γη)均增加;随着B增加,η_(max)、和ηP_(max)均减小,γη不变;随着ρ增大,P_(max)、γP和γη先增大后减小,η_(max)和ηP_(max)增大;比热模型对循环性能不产生定性的影响仅产生定量影响,非理想气体比热模型条件下得到的P_(max)、η_(max)、ηP_(max)、γP和γη最小.本文所得结论对实际热机的设计有一定的参考意义.

一种新型三相双频PWM整流器

为了能够抑制开关纹波,同时提高整流器的转换效率,此处提出了一种新型三相双频脉宽调制(PWM)整流器拓扑结构和控制方法。三相双频PWM整流器由功率整流单元和辅助单元组成。功率整流单元以低开关频率将有功功率从电网传输到负载,从而减少开关器件的损耗,提高转换效率。辅助单元以高开关频率运行,其作用是消除功率整流单元产生的电流纹波,改善电能质量。该整流器采用前馈方式消除开关纹波,因此可以避免参考电流的提取和控制带宽的限制。介绍了三相双频PWM整流器的拓扑结构和纹波消除原理,并给出了相应的控制策略。最后,在10kW实验样机上验证了三相双频PWM整流器的性能。

论地方性法规的空间效力

地方性法规的空间效力是指地方性法规在什么空间范围内具有法律效力。地方性法规的空间效力可以分为“整体效力”“局部效力”“特定效力”和“区外效力”四种形式,其中“区外效力”是地方性法规的空间效力最鲜明的效力特征。我国现行宪法、立法法和有关法律并没有确立地方性法规的一般性空间效力,只是对“局部效力”和“特定效力”在制度上加以明确,对于地方性法规在“本行政区域”之外是否具有法律效力没有作出禁止性规定。从经济特区法规、自治条例和单行条例的立法程序来看,都不能作出否定地方性法规所具有的“区外效力”的结论。地方性法规的“区外效力”在横向和纵向两个方面进行效力延伸,横向空间效力是指地方性法规在其他行政区域的法律效力,纵向空间效力是指地方性法规能否约束中央层面的执法和司法审判机构。根据中国法的“域外适用”理论和政策要求,在确保地方性法规的合宪性、合法性前提下,地方性法规的“区外效力”应当得到制度的肯定和支持。

“双碳”目标下火电厂CO_(2)计量技术研究现状与展望

中国电力行业CO_(2)排放量是CO_(2)排放的主要来源,其中火电厂CO_(2)排放量在电力行业中占比最大。在“双碳”目标下,CO_(2)计量技术可以实现对火电厂中CO_(2)排放量的直观判断,为火电厂CO_(2)减排提供重要支撑,促进火电厂参与碳交易,带动区域经济发展。结合国内外政策,讨论了目前通用CO_(2)计量方法的实施进展,总结归纳了以碳核算为主、碳监测为辅的火电厂CO_(2)计量方法存在的问题,并对火电厂CO_(2)计量技术应用的重难点进行了分析。最后,对火电厂CO_(2)计量技术的发展及应用进行了展望。

一种可拓展双输入高增益DC/DC变换器

针对光伏发电系统中光伏电池板集成汇流的需求,提出了一种可拓展双输入高增益DC/DC变换器。该变换器采用了一种新型拓扑结构,可在实现输入输出电压高增益变换的同时降低了开关器件的电压应力。此外,所提变换器还具有可拓展性,可以根据不同的光伏电池板数量和输出电压要求对端口进行扩展,从而降低系统的复杂性和成本。首先详细介绍了所提变换器的拓扑结构,并推导出变换器在不同工作模态下的运行原理。然后,对该变换器的增益特性、开关器件的电压和电流应力、关键器件的参数选择和损耗计算等方面进行了深入的理论分析。最后,搭建了一台输出功率为1 kW的实验样机,并进行了实验测试。实验结果验证了所提变换器理论分析的正确性和可行性。

双耦合SP-S补偿紧凑型抗偏移WPT系统

在无线电能传输(wireless power transfer,WPT)系统中,偏移是不可避免的,偏移会引起系统参数的变化从而影响系统的传输性能。基于S-S和P-S补偿拓扑,提出一种具有抗偏移特性的双耦合SP-S补偿的紧凑型WPT系统。该系统采用两个同轴布置、相互解耦的圆角方形线圈作为能量的发射线圈,其与单一方形接收线圈均有耦合,提升了X方向和Y方向的抗偏移容忍度。通过谐振参数配置使接收线圈在偏移的过程中,一个线圈回路的输出增加,另一个线圈回路输出减少,从而使系统输出随接收线圈位置偏移波动平缓。提出方形解耦线圈结构参数的设计方法,并分析发射端并联补偿电容对输出抗偏移性能的影响。最后,搭建实验平台验证该方法的有效性与系统的抗偏移能力。

一种用于反无人机设备的三频段功率放大器

在现有双频匹配理论的基础上,设计了一种可同时工作在1.5/2.4/5.8 GHz三个频段的射频功率放大器。为满足对抗无人机的实际应用需求,首先匹配2.4 GHz和5.8 GHz两个频率,然后匹配1.5 GHz,并设计相应的三频段输入输出匹配网络,完成了三频段功率放大器整体电路的设计。ADS仿真结果表明,当输入功率为28 dBm时,在三个频段设计的射频功率放大器的输出功率分别为39.88 dBm、40.94 dBm和39.25 dBm,效率分别达到了46.52%、60.54%和39.40%。该功率放大器可应用在基于信号抑制或信号欺骗的反制无人机设备中,提升放大器效率与设备集成度。

考虑电压-无功调节的台区互联装置规划方法

伴随分布式能源广泛接入低压配电网,其对配电网运行灵活性和消纳能力的要求不断提高。利用低压柔性互联装置将独立运行的低压配电台区分区互联,避免传统电压调节和无功补偿装置频繁动作。考虑到柔性互联装置造价昂贵,协同传统电压-无功调节装置,文中提出低压柔性互联装置的选址定容规划方法。首先,分析低压柔性互联装置拓扑和运行方式,建立其潮流模型。其次,建立低压柔性互联装置优化配置的双层规划模型,上层规划以年综合费用最小为目标,下层规划考虑电压-无功协调控制时间序列模型,以运行成本和电压偏差最小为目标,基于粒子群优化算法和混合整数二阶锥规划算法交替求解,得出配电系统最优柔性互联方案和最优运行方式。最后,在IEEE 33节点系统上进行实例分析,验证该双层规划算法的有效性。结果表明,所提方法能有效减少柔性互联装置的过度布置,同时减少由分布式能源频繁波动造成的运行成本。将模型凸化并线性化的方法明显提高了求解效率。

基于需求功率预测的电动拖拉机能量管理策略

针对电动拖拉机在犁耕工况下电机需求电流波动比较大的特点,为了改善动力电池的输出电流过高或过低及电动拖拉机犁耕持续作业时间短的现象,利用超级电容高功率密度的特点,设计了一种锂电池+超级电容结构的双电源电动拖拉机,并建立了Amesim/Simulink联合仿真模型。以模型预测控制作为双电源系统的能量管理方法,基于长短期记忆神经网络建立电动拖拉机犁耕工况下的需求功率预测模型,使用动态规划算法求解最佳的锂电池输出电流。仿真结果表明:相比于模糊控制策略,基于模型预测控制策略有效降低了锂电池大电流放电的频率且峰值电流降低了40%,有效提高了锂电池的使用寿命;超级电容的SOC保持在比较高的范围内,且电动拖拉机在犁耕工况下的单位里程能量消耗降低了2.17%,实现了双电源电流分配最优,提高了电动拖拉机的动力性和经济性。

磁控溅射法制备的硫化镉缓冲层的铜锌锡硫薄膜太阳电池性能

利用磁控溅射法制备硫化镉薄膜,研究硫化镉薄膜作为缓冲层的铜锌锡硫薄膜太阳电池性能.进一步地,采用双功率溅射的方法,减轻溅射过程对吸收层的损伤,增加了铜锌锡硫薄膜太阳电池的开路电压和填充因子,提高了光电转换效率,最终获得了光电转换效率为7.0%的铜锌锡硫薄膜太阳电池.

基于功率控制环扰动的DC-DC变换器能量信息一体化研究

针对实现DC-DC变换器之间的信息交互较为复杂的问题,提出了一种基于功率控制环扰动实现其能量信息一体化的方法。通过在DC-DC变换器的传统功率控制环中叠加二进制频移键控(binary frequency shift keying,2FSK)信号作为扰动,将数据信息叠加到传统脉冲宽度调制(pulse-width modulation,PWM)信号中,使得该PWM信号同时包含数据信息,实现能量信息一体化。首先,给出基于2FSK的功率/数据双载波调制以及实时的滑动离散傅里叶变换(sliding discrete Fourier transform,SDFT)解调方案。然后,通过对Buck变换器的能量信息一体化模型进行小信号建模与分析可知,降低输入阻抗可提升通信的信噪比。最后搭建一个由两个Buck变换器并联的实验装置进行验证。实验结果表明在稳态和负载突变的工况下均可实现3 kb/s的稳定通信,验证了所提方法的可行性。该方法使得DC-DC变换器能同时进行功率变换和数据传输,提升数字化和智能化水平。