The shipboard power system (SPS) is expected to be configured as a hybrid microgrid (MG) to realize redundant bus design and high penetration of renewables (REs). Point-of-load (POL) inverters in SPSs play a critical role to feed for sensitive ac load. To realize voltage-oriented control objective under load disturbance due to load uncertainty or nonlinearity, this paper proposes an ellipse-optimized composite back-stepping control strategy for a POL inverter. Firstly, the backstepping algorithm is harnessed to derive the pseudo-inductor-current-loop reference and decoupled switching functions in d-q frame, which can rigorously guarantee the global large-signal stability of the system. A Kalman filter is designed to estimate the load current and feedforward it to the backstepping controller for load disturbance rejection, saving three current sensors. The controller gains are quantitatively selected to achieve the optimal system damping and maximized dynamic response, which can be intuitively interpreted via an ellipse-based strategy from a geometrical point of view. Rigorous stability proof and robustness analysis of the system is also provided. Finally, simulation and experimental results verify the effectiveness of the proposed control scheme.

中文翻译：

---

舰船电力系统负载扰动下负载点逆变器的椭圆优化复合反步控制策略

船上电力系统（SPS）有望配置为混合微电网（MG），以实现冗余总线设计和可再生能源（RE）的高渗透率。SPS中的负载点（POL）逆变器在为敏感的交流负载供电方面起着至关重要的作用。为了实现由于负载不确定性或非线性引起的负载扰动下的电压定向控制目标，本文提出了一种基于椭圆优化的POL逆变器复合反步控制策略。首先，利用反推算法推导伪电感电流环参考和去耦开关函数。dq框架，可以严格保证系统的全球大信号稳定性。卡尔曼滤波器设计用于估算负载电流，并将其前馈至反步控制器以抑制负载干扰，从而节省了三个电流传感器。定量选择控制器增益以获得最佳的系统阻尼和最大的动态响应，这可以通过基于椭圆的策略从几何角度直观地解释。还提供了系统的严格稳定性证明和鲁棒性分析。最后，仿真和实验结果验证了所提控制方案的有效性。