Real-Time Model Predictive Control for Shipboard Power Management Using the IPA-SQP Approach

Abstract

Shipboard integrated power systems, the key enablers of ship electrification, call for effective power management control (PMC) to achieve optimal and reliable operation in dynamic environments under hardware limitations and operational constraints. The design of PMC can be treated naturally in a model predictive control (MPC) framework, where a cost function is minimized over a prediction horizon subject to constraints. The real-time implementation of MPC-based PMC, however, is challenging due to computational complexity of the numerical optimization. In this paper, an MPC-based PMC for a shipboard power system is developed and its real-time implementation is investigated. To meet the requirements for real-time computation, an integrated perturbation analysis and sequential quadratic programming (IPA-SQP) algorithm is applied to solve a constrained MPC optimization problem. Several operational scenarios are considered to evaluate the performance of the proposed PMC solution. Simulations and experiments show that real-time optimization, constraint enforcement, and fast load following can be achieved with the IPA-SQP algorithm. Different performance attributes and their tradeoffs can be coordinated through proper tuning of the design parameters.Index Terms-Integrated perturbation analysis and sequential quadratic programming (IPA-SQP), integrated power system (IPS), model predictive control (MPC), power management control (PMC), real-time optimization.

Simulation Model and State Analysis of Ship Transmission Line

“…When the arc extension rate elongspd is changed, r=0.1 is taken and when the parameters are set τ 0 =0.1ms, l 0 =0.1m, cosβ is changed between 0.01-1. Formula (2) shows that elongspd is changed between 3.465/ms-1.75m/ms, and 10 sets of sample data are obtained. The fault current transient peak I max and its increment ΔI max are compared.…”

“…Because the line has an unavoidable defect in its own material, manufacturing technology, and laying process, it is affected by the environmental factors such as power supply pressure, oil mist, water vapour and temperature on the line insulation layer or line junction, resulting in the gradual aging of the insulating layer and the appearance of the local arc. As the environment of the ship is relatively humid and there is more oil pollution, it is easier to generate the eliminating arc, causing current leakage, partial discharge and other phenomena [2]. According to research, early failures usually occur near the peak of the voltage waveform and stop at the first zero crossing point of the current waveform [3].…”

Battery Power Smoothing Control in a Marine Electric Power Plant Using Nonlinear Model Predictive Control

“…At every step, the free variables are optimized with respect to the cost function and constraints, and only the variables for the first step are applied to the system. Multiple suggestions using MPC in marine power plants already exist, such as [1], [21], [22], [23].…”

Smart Shipboard Power System Operation and Management

“…With regard to a shipboard PMS design and control, extensive research works have been initiated recently and many researchers around the world have elaborated on the issues involved [8][9][10][11][12][13][14][15][16][17][18][19][20]. For example, in [8] the economic operation of a vessel equipped with PVs and ESSs is studied for different power supply architectures, and analytic formulas are reported for calculating the system marginal cost, taking into account the energy and power balances for a given time period.…”

“…The same optimal power generation scheduling for a shipboard power system with and without energy storage options is presented in [9] and the system behavior is investigated under each working scenario, accordingly. In [10,11], a model predictive control (MPC)-based PMS for an onboard power system that includes multiple power sources and loads, such as the ship propulsion system and high power pulsed-type electrical load, is proposed and formulated as a real-time optimization problem where minimum cost of operation is considered as the objective. Similar real-time optimal dispatch of an AES enabled by integrated power systems is proposed in [11] and formulated as a simplified two-level optimization problem for improved computational efficiency.…”