【作者】 龚飞；

【导师】 林桦；

【作者基本信息】 华中科技大学 ， 电气工程， 2015， 硕士

【摘要】 随着传统能源储量越来越少,人们越来越开始追求能源的高效利用。在船舶工业中,越来越多的货轮开始采用轴带发电技术以提高能源利用率及减少经济成本。轴带发电系统中,轴带电机的选择至关重要。无刷双馈电机由于取消了电刷及滑环,运行可靠性大大提高,因而越来越多的在轴带发电领域受到关注。因此,本文对无刷双馈电机轴带发电系统中的负载侧变换器的控制做了系统研究。针对无刷双馈电机这一新型电机,首先阐明了其工作原理,详细推导了其稳态等效电路,基于稳态等效电路求出了其能量传递关系。接着,在三相静止坐标系及旋转坐标系建立了其动态数学模型,并得出了其矢量等值电路。通过Plecs仿真软件搭建了无刷双馈电机的仿真模型,验证了模型的有效性。建立了负载侧变换器的数学模型,根据控制目标选择了直接电流控制,进行了控制器参数设计。基于独立发电系统的特点,设计了负载侧变换器的启动策略及无功补偿策略。最后在Plecs仿真软件中进行了仿真验证,首先进行了负载侧变换器的单级仿真,接着通过与电机侧变换器级联,机侧变换器采用标量控制,进行了两级级联发电仿真。针对独立发电系统负载电压谐波含量较高这一问题,分析了其产生原因。在此基础上,给出了各种滤波电路,并通过比较选定最优的滤波电路。分析了滤波器引入产生的稳定性问题,采用了无源阻尼法及基于数字控制的无阻尼法来改善稳定性问题。最后通过仿真及实验验证了上述方法的有效性。搭建了无刷双馈电机变速恒频独立发电系统的实验平台,编写了实验程序,选取了负载侧变换器的电感电容参数。在实验平台上进行了变速恒频的发电实验,得到了比较理想的稳态及动态性能,验证了上述控制策略的准确性与可靠性。更多还原

【Abstract】 As the traditional fossil energy reserves are less and less, we are pursuring the efficient use of energy. In the ship industry, more and more ships are beginning to use the shaft power generation technology to improve energy utilization efficiency and reduce economic cost. In shaft power generation systems, it is essential to choose shaft generators. The brushless doubly fed generator(BDFG) is very fit for this kind of generation system due to its cancellation of the brush and slip ring which can improve its reliability and safty, so more and more attention is paid to BDFG. Therefore, in this paper, we do a systematic study on the control strategy of load side converter in the shaft power generation systems using BDFG.As BDFG is a new type of electric machine, firstly we illustrate the working principle of it, and then establish the steady-state equivalent circuit which can help us derive the energy relationship between the control windings and power windings. Then we establish mathematical model of BDFG in the three-phase static coordinate and rotating coordinates, and obtain its vector equivalent circuit. At last, we establish the simulation model of BDFG in Plecs, and simulations verify the validity of the model.Then we give the mathematical model of the load side converter(LSC),and according to the control target, the controller is well designed. We also design the starting strategy and reactive power compensation strategy of LSC which can be used in stand-alone power generation systems. At last, simulation verification is carried out in the Plecs simulation software. We first simulate the LSC in Plecs to verify the control strategy. With the machine side converter(MSC) using scalar control, we also cascade the MSC and LSC in Plecs to model the actual systems.In view of load voltage harmonic content being high in the stand-alone power generation systems, firstly we analyzed its causes. On this basis, we put forward a variety of filter circuits, and choose the best through comparison. But the filter may make a system unstable, we proposed the passive damping method and no damping resistor method based on the digital control to improve the stability. Finally, the validity of the methods is verified by simulation and experiment.Finally, we build an experimental platform of BDFG variable speed constant frequency stand-alone generation system, and program in C language in DSP controllers. Through the experiment, we obtain the ideal steady state and dynamic performance, which verifies the truth of the above theory.更多还原