双馈感应发电机与输电线路串联电容补偿之间的次同步控制相互作用（SSCI）是引发双馈风电交流并网系统次同步振荡（SSO）的主要原因。该文通过建立双馈风电交流并网系统的阻抗模型,分析风电机组不同控制参数对系统SSO的影响程度,提出一种可等效电流环控制参数调整且兼顾基频控制性能的附加阻尼控制方法。为提升对振荡模态迁徙的适应性和鲁棒性,进一步将实时测频与模糊控制相结合,形成一种可根据振荡频率自动调整附加阻尼控制参数的SSO自适应抑制策略。最后,基于Matlab/Simulink仿真平台,验证该文所提出的SSO自适应抑制策略的正确性与有效性。

The sub-synchronous control interaction （SSCI） between the doubly-fed induction generator （DFIG） and the series com-pensation capacitor （SSC） of the transmission line is the main reason for the sub-synchronous oscillation （SSO） of the dou-bly-fed wind power AC grid-connected system. By establishing the impedance model of the doubly-fed wind power integration system with SSC, this paper analyzes the influence of different control parameters of the wind turbine on SSO, and proposes an additional damping control method that is equivalent to the adjustment of current loop parameters and take into account the fundamental frequency control perfor-mance. In order to improve the adaptability and robustness to the oscillation mode migration, this paper further combines real-time frequency measurement with fuzzy control to form an adaptive suppression strategy that can automatically adjust additional damping control parameters according to the oscillation frequency. Finally, based on the Matlab/Simulink simulation platform, the correctness and effectiveness of the adaptive suppression strategy proposed in this paper are verified.

水电机组调节系统对水电站的安全稳定运行起着关键的作用，不当的调节参数会弱化系统的阻尼，诱发水电机组功角振荡行为。为保证水电机组稳定运行，提出了一种兼顾功角稳定的模糊滑模控制策略。首先，考虑水力与机电系统暂态特性之间的相互影响，建立了包含弹性水击的水轮机内特性模型和三阶发电机模型的水电机组调节系统模型，并分析不同工况下系统的振荡特性。其次，通过将Δδ及ΔV_t 引入滑模面函数，改善控制器输出对系统阻尼的影响，提升系统功角输出的稳定性。在此基础上，以系统机械功率为参考指标，设计了一种基于指数规律调整的变速趋近律，使收敛速度能够随工况变化及时调整。不同工况下的仿真结果表明，提出的控制律在系统受到功率扰动时，能够有效改善水电机组功角振荡行为，抑制系统低频振荡的发生，提高了系统的稳定性和控制器的鲁棒性。

The hydro-turbine regulating system plays a key role in the safe and stable operation of hydropower plants. Improper regulation parameters can weaken the damping of the system and induce hydropower unit power angle oscillation behavior. In order to ensure the stable operation of hydropower units， this paper proposes a fuzzy sliding mode control strategy based on improved reaching law and sliding manifold. Firstly， considering the mutual influence between the transient characteristics of hydraulic and electromechanical systems， a hydro-turbine regulating system containing the internal characteristics of the hydraulic turbine with elastic water hammer and the third-order generator model is established， and the oscillation characteristics of the system under different operating conditions are analyzed. Secondly， the stability of the system rotor angle is enhanced by introducing Δ δ and Δ V _t into the sliding manifold to improve the influence of the controller output on the system damping. On this basis， taking the mechanical power of the system as the reference index， a variable speed reaching law based on the exponential law adjustment is designed， so that the convergence speed can be adjusted in time with the change of working conditions. Simulation results under different working conditions show that the proposed control law can effectively improve the power-angle oscillation behavior of the hydropower unit and suppress the occurrence of low-frequency oscillation of the system when the system is subject to power disturbance， which enhances the stability of the system and the robustness of the controller.

含小水电微电网受源荷不确定性影响易产生较大的功率波动,离网状态下易导致微电网系统停电、弃电的发生。为了充分考虑含小水电微电网功率、能量的平衡特性,提高含小水电微电网运行的经济性和鲁棒性,提出一种基于功率能量特性的含小水电微电网储能优化配置方法。首先,分析了含小水电微电网的功率能量平衡机理,提出了该微电网的功率能量特性模型;然后,在含小水电微电网功率能量特性模型和源荷不确定性模型的基础上,提出了基于功率能量特性的随机场景分解聚类方法和储能容量配置方法。最后,以某地区离网型含小水电微电网为仿真算例,通过与现有方法进行结果对比和影响因素分析,验证了所提方法的有效性。

Small hydropower-containing microgrids are susceptible to large power fluctuations caused by source-load uncertainty, and off-grid conditions can easily lead to power outages and power abandonment of the microgrid system. To fully consider the power and energy balance characteristics of microgrids containing small hydropower sources and improve their economy and robustness, this study proposes a method for optimizing the configuration of energy storage in microgrids containing small hydropower using the power and energy characteristics. First, the power-energy balance mechanism of a microgrid containing small hydropower is analyzed, and a power-energy characteristic model of the microgrid is proposed based on the power-energy characteristic model of the microgrid containing small hydropower and the source-load uncertainty model. A stochastic scenario decomposition clustering method based on the power-energy characteristic and the energy storage capacity configuration method is also proposed. Finally, the effectiveness of the proposed method is verified by comparing the results with those of existing methods and analyzing the influencing factors using an off-grid microgrid containing small hydropower in a region as a simulation example.

为保障海水淡化系统在发电机组处于低负荷工况下的制水能力，提高全厂的经济性，以某4台水电联产机组为例进行研究，利用EBSILON软件对4台机组进行热力学建模，并验证了模型的准确性；分析符合海水淡化制水条件的汽源，并提出满足低负荷工况下海水淡化制水的3种抽汽方案；基于热力学经典理论，利用热力学模型对3种抽汽方案进行论证分析，并通过对3种抽汽方案的煤耗量和改造成本进行比较分析，得到经济性最优的低负荷供汽方案。研究结果对电厂节能减排、提高电厂运行经济效益具有一定指导意义。

In order to ensure the water production capacity of the seawater desalination system under the low load condition of the generator units, and improve the economy of the whole plant, four dual-purpose power and water plant units were taken as examples. The thermodynamic modeling of the four units was carried out by EBSILON software, and the accuracy of the model was verified. The steam sources meeting the conditions of sea fresh water production were analyzed, and three steam extraction schemes meeting the conditions of low load were put forward. Based on the classical theory of thermodynamics, the thermodynamic model was used to demonstrate and analyze the three steam extraction schemes. Moreover, through the comparative analysis of the coal consumption and transformation cost of the three steam extraction schemes, the optimal low load steam supply scheme was obtained. This study has a certain guiding significance for the power plant energy saving and emission reduction and improvement of the economic efficiency of power plant operation.