The standalone brushless doubly fed induction generator (BDFIG) has demonstrated excellent energy-saving performance in ship shaft power generation applications. As a standalone system, it exhibits unbalanced terminal voltages and poor performance under unbalanced loads. However, the existing control scheme of grid-connected BDFIGs cannot be directly applied to stabilize the amplitude and frequency of terminal voltage when the rotor speed and electrical load vary. This paper presents a new sensorless control scheme for the standalone BDFIG under unbalanced load conditions in the ship shaft power generation system. A second-order generalized integrator-based quadrature signal generator is introduced to realize the rotor speed observer for the standalone BDFIG feeding unbalanced loads. The compensation method of negative-sequence power winding voltage is proposed to eliminate the negative-sequence component of the unbalanced power winding voltage. Comprehensive experiments are carried out on a prototype BDFIG with and without the compensation of negative-sequence power winding voltage. The good performance of the proposed sensorless control scheme is verified by the experimental test results.

中文翻译：

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船轴发电系统中不平衡负载供电的独立无刷双馈感应发电机的无传感器控制


独立无刷双馈感应发电机（BDFIG）在船舶轴发电应用中表现出了优异的节能性能。作为一个独立的系统，它在不平衡负载下表现出不平衡的端电压和较差的性能。然而，当转子速度和电力负载变化时，现有的并网BDDFIG控制方案不能直接应用于稳定端电压的幅值和频率。本文提出了一种新的船轴发电系统不平衡负载条件下独立 BDFIG 的无传感器控制方案。引入基于二阶广义积分器的正交信号发生器来实现独立 BDFIG 馈送不平衡负载的转子速度观测器。为了消除不平衡功率绕组电压的负序分量，提出了功率绕组电压负序补偿方法。在带负序功率绕组电压补偿和不带负序功率绕组电压补偿的BDDFIG样机上进行了综合实验。实验测试结果验证了所提出的无传感器控制方案的良好性能。