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燃油经济性好是变速柴油发电机组的一大优势,而柴油机运行转速与燃油消耗率密切相关。以变速柴油发电机组为研究对象,建立了变速柴油发电机组的数学模型,以燃油消耗率最低为准则,用数学模型寻优和试验数据寻优两种方法开展了变速柴油发电机组的最佳运行转速研究;并进行了变速柴油发电机组油耗试验。试验结果表明:在最佳运行转速曲线上运行的变速柴油发电机组的燃油消耗率小于恒速模式下运行时的燃油消耗率;试验数据寻优得到的最佳运行转速曲线的节油性更好。 相似文献
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1前言海茵茨曼负荷控制器LKG01的应用,能使一台或多台柴油发电机组与电网并联运行.通过控制发电机组的负荷,达到控制电网输出功率和多台发电机组电网输人功率的目的(图1).图!限制电网供电时机组向电网供电的特性装上负荷控制器的并联系统,大致有这样一些优点:a一运行中不会出现故障;b.在负荷有变动时,从电网输出的频率可确保稳定;。可实现低负荷时由电网供电.这一点对整个能源装置来说很重要.因为在这些能源装置处,控制发热是一个很重要的因素;d,并联运行过程中,可控制电站最小供电量.图2所示为机组与电网配有负荷分… 相似文献
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光伏发电系统输出的最大功率随外界环境变化而波动,无法满足负荷的供电需求,针对该问题,建立了基于储能系统的光伏发电系统结构,介绍了光伏发电系统运行原理,分析了系统功率与直流母线电压的关系,设计了无源式储能系统和有源式储能系统对功率进行缓冲以满足控制目标.仿真结果表明,有源式储能系统较无源式储能系统有更好的功率调节作用,通过双向DC-DC变换器的储放能量自动切换控制,使得光伏发电系统输出的功率与负荷需求功率良好匹配,直流电压稳定. 相似文献
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当长期运行于并网状态的微电网转为孤岛运行时,若微电源和储能元件容量不足以保证微电网内所有负荷的正常供电,为最大限度地保证重要负荷供电不中断,需要切除微电网部分负荷。本文提出一种基于储能剩余电量预估的微电网切负荷策略,根据微电网孤岛运行期间微电源发电功率和负荷用电功率的预测值,对储能装置储电量进行预测估计和比较分析,按照微电网实时功率平衡原则和负荷分级体系,优化确定不同级别负荷的投切时刻,以保证微电网内重要负荷的持续供电和其余各级负荷停电时间最短。建立基于该切负荷策略的算例微电网仿真系统,仿真结果表明此策略的正确性和有效性。 相似文献
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《International Journal of Hydrogen Energy》2022,47(91):38495-38505
One of the trends in the development of the electric power industry in the world is the use of renewable resources. In recent years, the development of hydrogen energy has been widely discussed, which, when combined with renewable energy sources, makes it possible to obtain “green” hydrogen. One of the promising solutions for obtaining green hydrogen is the development of wind energy-hydrogen systems. However, one of the limiting factors, in addition to economic aspects, are technical limitations. Sustainable hydrogen production is complicated by the variability of wind energy. In addition, energy systems with a predominant share of wind power units have a low total inertia value. Consequently, such systems become more sensitive to changes in load modes in the grid and become less stable in emergency modes. Together, these facts reduce the reliability of wind energy-hydrogen system. The paper proposes to increase the stability of wind energy-hydrogen system and power system as a whole to apply synthetic inertia for wind power plants. It is shown that by adjusting the parameters of synthetic inertia can provide not only the required inertial response, but also increase the dynamic stability of the power system and as a consequence wind energy-hydrogen system. The influence of the measurement window time and calculation of the frequency change rate, which is important in certain modes, is also investigated. 相似文献
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Investigation of thermoelectric generators connected in different configurations for micro‐grid applications
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This research work investigates the power‐current (P‐I) and voltage‐current (V‐I) characteristics of the thermoelectric modules (TEMs) in series‐parallel configurations under homogeneous and heterogeneous temperature difference (ΔT) condition. To study its performance, 5 different series‐parallel combinations were formed using 16 TEMs. The comparisons among the different configurations have been done to determine the optimal series‐parallel configuration. The total load power extracted from 16 individually connected TEMs was 18.2 W, which was placed as a reference load power. The optimal series‐parallel combination for maximizing the load power is square series‐parallel configuration, whose maximum load power is 95.5%, compared to the reference load power. Moreover, in square series‐parallel configuration, the total internal resistance value that remains constant is equal to the internal resistance of a single TEM, and the total open‐circuit voltage increases gradually on adding any number of TEMs. Thus, it produces higher load voltage and higher load current simultaneously, which is recommended to power DC micro‐grid applications. Furthermore, the series, parallel, and square series‐parallel configurations are connected as star to obtain 3 separate DC output to power the same application. The performance of TEMs under various configurations is analyzed, and the obtain results are verified experimentally. 相似文献
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双质量飞轮性能参数优化设计方法 总被引:1,自引:0,他引:1
双质量飞轮用于降低汽车传动系统怠速工况和常速行驶工况下的扭转振动.在怠速工况下发动机、双质量飞轮与传动系统组成的多质量扭振模型的基础上,建立了双质量飞轮第1、2阶设计模型,并推导出双质量飞轮转动惯量、怠速级扭转刚度与系统固有频率的关系,结合减振原理,建立了其转动惯量分配和怠速级扭转刚度的设计方法;根据双质量飞轮的工作原理,推导出行驶级扭转刚度与发动机最大转矩、怠速级扭转刚度的关系,并以避免低速区和常速区动力传动系统发生主谐次扭转振动为目标,建立了多级扭转刚度的设计与优化方法.发动机的扭振试验验证了设计模型和设计方法的正确性,怠速工况下第1阶固有频率降至7.9,Hz,行驶工况下双质量飞轮对发动机速度波动衰减了80%左右. 相似文献
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鉴于抽水蓄能机组水泵工况停机断电控制策略的制定受水、机、电等因素影响,以黑麋峰电站为例,分析了机组不同水头下水泵工况停机过程中,不同导叶开度断电条件下过渡过程的特性、停机过程机组振动/摆度和压力脉动等关键测点的稳定性参数变化,并对比了水泵工况停机过程与开机过程抽水调相转抽水工况下稳定性参数的差异,结合机组GCB特性确定水泵工况停机过程断电的最佳负荷和导叶开度,优化水泵工况停机策略,实现过渡过程、稳定性与GCB电气寿命指标最优。优化后的水泵工况停机策略能够保证机组安全运行,且停机断电负荷满足相关行业标准。 相似文献
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为了适应电网发展的需求,具备一定地形地质条件的常规水电站可考虑通过增装蓄能机组扩建成混合式抽水蓄能电站。针对共用引水系统的常规机组和蓄能机组实际运行特点,基于特征线法和瞬变流理论,建立了水力过渡过程计算模型,并结合工程实例模拟了混合式抽水蓄能电站可能发生的多种过渡过程工况,确定了合理的蓄能机组的关闭规律,复核了已建调压室的稳定性。结果表明,通过对新增蓄能机组导叶启闭规律的独立调控,一定程度上可维持混合式抽水蓄能电站输水发电系统的安全稳定,避免增设调节保证设施;蓄能机组导叶关闭时间延长,在降低自身蜗壳末端最大压力的同时,可抑制常规机组甩负荷后的蜗壳末端压力及最大转速上升;对于既有调保措施威胁最大的相继增负荷工况,引用流量较大的常规机组优先增负荷比引用流量较小的蓄能机组优先增负荷引起的调压室最低涌浪值更高,更有利于调压室的稳定运行。 相似文献
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The overall efficiency of an induction motor drive system, powered by a PV array, drops significantly when the insolation condition varies away from its nominal level. This problem can be overcame using a control method in which the frequency of the inverter's PWM control signal is adjusted according to the insolation and temperature conditions. The motor speed, and therefore, the power delivered to the load, are adjusted by controlling the inverter's frequency. This eliminates the mismatch between the maximum power that is available from the source and the power that is required by the load. Simulation results presented in this paper show that using the proposed control system allows the induction motor drive system to maintain its optimum efficiency and deliver consistently more power to the load when insolation and temperature vary from the nominal level. This method also offers an improvement in the system stability 相似文献