同步发电机整流系统的运行实践表明，该类系统存在着运行稳定性问题。本文对此问题进行了深入的理论研究和试验研究。 本文将带整流负载的同步发电机ｄ、q轴变量的低频分量（含非周期分量）和高频分量分别加以处理。在忽略转子回路对高频电流的电阻和忽略阻尼绕组对低频分量的作用的条件下，分别建立了适用于三相和十二相同步发电机整流系统稳态和似稳态分析的电路模型。在此基础上，得出了单机整流带反电势负载系统和多机整流并联系统小扰动条件下的线性化模型。 对于十二相同步发电机整流系统，本文分别分析了接１ＰＲ和不接１ＰＲ时的运行过程和运行特性，导出了交、直流电压、电流的变换关系，从而为该类系统的运行参量计算及运行稳定性分析提供了可能性。 在上述工作的基础上，深入研究了三相和十二相同步发电机单机整流带反电势负载和多机整流并联系统在小扰动下的运行稳定性问题。得出了稳定判据;提出了运行稳定性的计算方法；阐明了该类系统运行稳定性问题的机理；分析了发电机电抗、线路阻抗、负载参数等诸多因素对单机和多机系统运行稳定性的影响。分析表明，同步发电机整流系统在小扰动下之所以运行不稳定，根本上是由发电机和系统的电磁过程而不是由系统的机电过程引起的。 本文分析了利用励磁闭环控制抑制系统低频振荡的机理，并提出了励磁闭环控制系统的设计方法。分别分析并比较了采用电压微分和电流微分作为抑制信号时的控制效果。提出了多机整流并联系统采用励磁闭环控制抑制振荡时，控制器设计的分离原理。 本文提出了同步发电机整流系统运行稳定性的试验方法，并对多种发电机整流系统在多种运行情况下的稳定性，进行了试验研究。试验结果与理论分析和计算结果相吻合。
The operation of synchronous generator-rectifier-load systems may be unstable under certain conditions. A detailed stability investigation of such systems is made in this paper.The d-and q-axis variables of a rectifier-loaded synchronous generator are resolved into low-frequency components (including periodic components) and high-frequency components. With the fact taken into account that the resistances of the rotor circuits to high-frequency currents and the effects of the damper windings on low-frequency components are negligible, the equivalent circuit models of the rectifier-loaded 3-phase and 12-phase synchronous generators are separately developed for steady-state and quasi-steady-state analysis. Furthermore, the corresponding linearized models are presented for the generator-rectifier-back emf load system and the generator-rectifier parallel system under small disturbances.The operation process and the characteristics of the 12-phase synchronous generator-retifier system with or without IPRs are analized, respectively. The AC-DC voltage and current relations of the system are deduced for performance calculations and stability analysis.The operational stability of the 3-phase and 12-phase synchronous generator-rectifier-load systems is studied in detail for the multimachine-rectifier parallel system as well as the single machine-rectifier-back emf load system. The criterion of stability of the sytem is obtained and the stability calculation method is proposed. The effects of the generator reactances, the line resistances, the load parameters, etc. on the system*s stability are examined. A physical interpretation is given to the instability of the system. The analysis makes it clear that the instability of the system under small disturbances is essentially caused by the electromagnetic process in the generator and system and not by the electromechanical process in the system. It is shown that the closed-loop excitation control can be adopted to suppress the low-frequency current oscillations in the system. The design method of the excitation control unit is presented. The principle of separation is proposed as the guiding rule in designing the generators* excitation unite of the multimachine-rectifier parallel system to make its operation stable.A lot of tests are made on various systems and under different operating conditions. The test results are in close agreement with the results obtained by analysis and calculations.
