# Modeling and Stability Analysis of Hybrid PV/Diesel/ESS in Ship Power System

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## Abstract

**:**

## 1. Introduction

- high energy density and long working lifecycle;
- fast response to smooth the frequency fluctuations;
- high efficiency with a lower loss;
- flexible for an application as a decentralized power supply unit;
- wide operating temperature range, and so on.

## 2. Hybrid Ship Power System Configuration and Components

#### 2.1. Hybrid Ship Power System Structure

#### 2.2. Models of System Components

#### 2.2.1. PV Generation System

#### (1) Solar Irradiation Simulation

#### (2) PV Model

_{2}emissions [23], so a detailed PV model with maximum power point tracing control method is developed in the paper. The PV generation consists of 2000 PV panels with the rated power of 290 kW, a boost converter and a bidirectional converter. The structure of the PV model is described in Figure 3.

#### 2.2.2. Diesel Generator

#### 2.2.3. Flywheel Energy Storage System

^{2}); $\omega $ is the angular speed of flywheel (rad/s).

#### 2.2.4. Converter

_{ref}, which is set to 410 V.

#### 2.2.5. Loads

## 3. Control Strategy for the Hybrid Ship Power System

#### 3.1. Maximum Power Point Tracking Algorithm

#### 3.2. P-Q Decoupled Control Strategy

_{d}) is set to be zero herein. Moreover, an LC filter is applied to the grid-connected converter for better smoothing. Table 2 presents the control parameters for the grid-connected inverter.

#### 3.3. Constant Torque Angle Control Method

_{ref}), the output power for the PV system can be smoothed to a specific value (250 kW).

_{d}is made to be zero and the torque of PMSM is only determined by quadrature-axis current I

_{q}. Thus, the torque for flywheel speeding up or slowing down can be controlled individually through adjusting PMSM quadrature-axis current I

_{q}. The whole control block is made up of an inner current loop and outer active power loop for determining the amount of the output power from the FESS, and the control parameters for the FESS are shown in Table 3.

## 4. Simulation Analysis

- First Case: Stability analysis considering PV connection and ship load fluctuations;
- Second Case: Stability analysis considering ship rolling;
- Third Case: Stability analysis considering the sudden changes of solar irradiation.

^{2}. The second stage (Second Case) is to study the impact of ship rolling on the PV generation system during 40 to 60 s. The last stage (Third Case) is to study hybrid system transient response when solar irradiation varies suddenly, which starts from 60 to 85 s.

^{2}. It is inevitable that the output power produced by the PV generation system will go through a sharp fluctuation, which will result in instability of the ship power system without FESS.

## 5. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## Symbols and Abbreviations

PV | Photovoltaic |

ESS | energy storage system |

FESS | Flywheel energy storage system |

SPWM | Sinusoidal pulse width modulation |

MARPOL | Marine Agreement Regarding Oil Pollution of Liability |

PMSM | Permanent Magnet Synchronous Motor |

SOC | State of charge |

MPPT | Maximum power point tracking |

DQ | Direct-axis and Quadrature-axis |

PQ | Active power and reactive power |

PWM | pulse width modulation |

DC | direct current |

I_{pv}, V_{pv} | PV array output current and voltage |

T | Duty cycle |

V_{ref} | excitation voltage reference per-unit value |

I_{f}, Ef | excitation current and voltage |

W | diesel generator speed per-unit value |

W_{ref} | diesel generator speed reference |

FL | the engine fuel intake |

Tm | the engine output shaft torque per-unit value |

J | the moment of inertia of flywheel rotor |

ω | the angular speed of flywheel or system angular frequency |

u_{sd}, u_{sq} | direct-axis and quadrature-axis voltage of stator winding |

i_{sd}, i_{sq} | direct-axis and quadrature-axis current of stator winding |

ψ_{sd}, ψ_{sq} | direct-axis and quadrature-axis flux linkage of stator winding |

L_{d}, L_{q} | direct-axis and quadrature-axis inductance of stator winding |

ω_{r} | angular speed of rotor |

R_{s} | resistance of stator |

ψ_{f} | flux linkage of rotor |

n_{p} | pairs of pole |

T_{e} | the electromagnetic torque of rotor |

I_{a}, I_{b}, I_{c} | phase current |

V_{abc} | phase to ground voltage |

V_{mppt} | the maximum power point tracking voltage |

θ | system voltage phase angle or rotor position of PMSM |

L | inductance of grid-connected inverter |

X_{d}, X_{q} | direct-axis and quadrature-axis reactance of PMSM |

ψ | Magnetic strength of PMSM |

## References and Notes

- The International Convention for the Prevention of Pollution from Ships. Available online: http://www.imo.org/en/About/Conventions/ListOfConventions/Pages/International-Convention-for-the-Prevention-of-Pollution-from-Ships-%28MARPOL%29.aspx (accessed on 18 January 2016).
- Mitra, P.; Venayagamoorthy, G.K. An adaptive control strategy for DSTATCOM applications in an electric ship power system. IEEE Trans. Power Electron.
**2010**, 25, 95–104. [Google Scholar] [CrossRef] - Hong, Y.; Pham, S.N.; Yoo, T.; Chae, K.; Baek, K.; Kim, Y.S. Efficient maximum power point tracking for a distributed PV system under rapidly changing environmental conditions. IEEE Trans. Power Electron.
**2015**, 30, 4209–4218. [Google Scholar] [CrossRef] - Sundareswaran, K.; Sankar, P.; Nayak, P.S.R.; Simon, S.P.; Palani, S. Enhanced energy output from a PV system under partial shaded conditions through artificial bee colony. IEEE Trans. Sustain. Energy
**2015**, 6, 198–209. [Google Scholar] [CrossRef] - Hajighorbani, S.; Radzi, M.A.M.; Kadir, M.Z.A.A.; Shafie, S. Dual search maximum power point (DSMPP) algorithm based on mathematical analysis under shaded conditions. Energies
**2015**, 8, 12116–12146. [Google Scholar] [CrossRef] - Haroun, R.; El Aroudi, A.; Cid-Pastor, A.; Garcia, G.; Olalla, C.; Martinez-Salamero, L. Impedance matching in photovoltaic systems using cascaded boost converters and sliding-mode control. IEEE Trans. Power Electron.
**2015**, 30, 3185–3199. [Google Scholar] [CrossRef] - Hill, C.A.; Such, M.C.; Chen, D.; Gonzalez, J.; Grady, W.M. Battery energy storage for enabling integration of distributed solar power generation. IEEE Trans. Smart Grid
**2012**, 3, 850–857. [Google Scholar] [CrossRef] - Zhang, T.; Yue, D.; O’Grady, M.J.; O’Hare, G.M.P. Transient oscillations analysis and modified control strategy for seamless mode transfer in micro-grids: A wind-PV-ES hybrid system case study. Energies
**2015**, 8, 13758–13777. [Google Scholar] [CrossRef] - Xu, Y.; Zhang, W.; Hug, G.; Kar, S.; Li, Z. Cooperative control of distributed energy storage systems in a micro grid. IEEE Trans. Smart Grid
**2015**, 6, 238–248. [Google Scholar] [CrossRef] - Wu, D.; Tang, F.; Dragicevic, T.; Vasquez, J.C.; Guerrero, J.M. A control architecture to coordinate renewable energy sources and energy storage systems in islanded microgrids. IEEE Trans. Smart Grid
**2015**, 6, 1156–1166. [Google Scholar] [CrossRef] - Akinyele, D.O.; Rayudu, R.K. Review of energy storage technologies for sustainable power networks. Sustain. Energy Technol. Assess.
**2014**, 8, 74–91. [Google Scholar] [CrossRef] - Ramli, M.M.M.; Hiendro, A.; Twaha, S. Economic analysis of PV/diesel hybrid system with flywheel energy storage. Renew. Energy
**2015**, 78, 398–405. [Google Scholar] [CrossRef] - Howlader, A.M.; Urasaki, N.; Yona, A.; Senjyu, T.; Saber, A.Y. A review of output power smoothing methods for wind energy conversion systems. Renew. Sustain. Energy Rev.
**2013**, 26, 135–146. [Google Scholar] [CrossRef] - Sebastián, R.; Peña Alzola, R. Flywheel energy storage systems: Review and simulation for an isolated wind power system. Renew. Sustain. Energy Rev.
**2012**, 16, 6803–6813. [Google Scholar] [CrossRef] - Boukettaya, G.; Krichen, L. A dynamic power management strategy of a grid connected hybrid generation system using wind, photovoltaic and Flywheel Energy Storage System in residential applications. Energy
**2014**, 71, 148–159. [Google Scholar] [CrossRef] - Abdel-Khalik, A.S.; Elserougi, A.A.; Massoud, A.M.; Ahmed, S. Fault current contribution of medium voltage inverter and doubly-fed induction-machine-based flywheel energy storage system. IEEE Trans. Sustain. Energy
**2012**, 4, 58–67. [Google Scholar] [CrossRef] - Hedlund, M.; Lundin, J.; de Santiago, J.; Abrahamsson, J.; Bernhoff, H. Flywheel energy storage for automotive applications. Energies
**2015**, 8, 10636–10663. [Google Scholar] [CrossRef] - Ren, G.; Ma, G.; Cong, N. Review of electrical energy storage system for vehicular applications. Renew. Sustain. Energy Rev.
**2015**, 41, 225–236. [Google Scholar] [CrossRef] - Lan, H.; Wen, S.; Hong, Y.-Y.; Yu, D.C.; Zhang, L. Optimal sizing of hybrid PV/diesel/battery in ship power system. Appl. Energy
**2015**, 158, 26–34. [Google Scholar] [CrossRef] - Shih, N.C.; Weng, B.J.; Lee, J.Y.; Hsiao, Y.C. Development of a 20 kW generic hybrid fuel cell power system for small ships and underwater vehicles. Int. J. Hydrogen Energy
**2014**, 39, 13894–13901. [Google Scholar] [CrossRef] - Lee, K.J.; Shin, D.S.; Lee, J.P.; Yoo, D.W.; Choi, H.K.; Kim, H.J. Hybrid photovoltaic/diesel green ship operating in standalone and grid-connected mode in South Korea—Experimental investigation. In Proceedings of 2012 IEEE Vehicle Power and Propulsion Conference (VPPC), Seoul Olympic Parktel, Seoul, Korea, 9–12 October 2012.
- Study on the Application of Photovoltaic Technology in the Oil Tanker Ship, Grant No. GK110900004, Execution period: January 2013–December 2015.
- Yan, R.; Saha, T.K.; Modi, N.; Masood, N.-A.; Mosadeghy, M. The combined effects of high penetration of wind and PV on power system frequency response. Appl. Energy
**2015**, 145, 320–330. [Google Scholar] [CrossRef] - Tankari, M.A.; Camara, M.B.; Dakyo, B.; and Lefebvre, G. Use of ultracapacitors and batteries for efficient energy management in wind-diesel hybrid system. IEEE Trans. Sustain. Energy
**2013**, 4, 414–424. [Google Scholar] [CrossRef] - Mukoyama, S.; Matsuoka, T.; Hatakeyama, H.; Kasahara, H.; Furukawa, M.; Nagashima, K.; Ogata, M.; Yamashita, T.; Hasegawa, H.; Yoshizawa, K.; et al. Test of REBCO HTS magnet of magnetic bearing for flywheel storage system in solar power system. IEEE Trans. Appl. Supercond.
**2015**, 25, 7–10. [Google Scholar] [CrossRef] - Valencia, P.A.O.; Ramos-Paja, C.A. Sliding-mode controller for maximum power point tracking in grid-connected photovoltaic systems. Energies
**2015**, 8, 12363–12387. [Google Scholar] [CrossRef] - Singaravel, M.M.R.; Daniel, S.A. MPPT with Single DC–DC converter and inverter for grid-connected hybrid wind-driven PMSG–PV system. IEEE Trans. Ind. Electron.
**2015**, 62, 4849–4857. [Google Scholar] [CrossRef] - Solar and PV data. Available online: http://solargis.info/doc/solar-and-pv-data (accessed on 28 May 2015).

MPPT Control | PI | SPWM | |||
---|---|---|---|---|---|

Open-circuit voltage | Short-circuit current | Sampling interval | P | I | Frequency |

450 V | 847 A | 0.001 s | 3 | 0.01 | 10 kHz |

LC Filter | Current Control | Voltage Control | SPWM | |||
---|---|---|---|---|---|---|

Inductance | Capacitance | P | I | P | I | Frequency |

0.5 mH | 500 uF | 50 | 0.001 | 120 | 0.001 | 12 kHz |

PMSM | Current Control | Active Power Control | ||||
---|---|---|---|---|---|---|

Rated Voltage | Rated Frequency | Moment of Inertia J | P | I | P | I |

200 V | 250 Hz | 58.824 kg*m^{2} | 1500 | 0.0001 | 100 | 0.001 |

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**MDPI and ACS Style**

Lan, H.; Bai, Y.; Wen, S.; Yu, D.C.; Hong, Y.-Y.; Dai, J.; Cheng, P.
Modeling and Stability Analysis of Hybrid PV/Diesel/ESS in Ship Power System. *Inventions* **2016**, *1*, 5.
https://doi.org/10.3390/inventions1010005

**AMA Style**

Lan H, Bai Y, Wen S, Yu DC, Hong Y-Y, Dai J, Cheng P.
Modeling and Stability Analysis of Hybrid PV/Diesel/ESS in Ship Power System. *Inventions*. 2016; 1(1):5.
https://doi.org/10.3390/inventions1010005

**Chicago/Turabian Style**

Lan, Hai, Yifei Bai, Shuli Wen, David C. Yu, Ying-Yi Hong, Jinfeng Dai, and Peng Cheng.
2016. "Modeling and Stability Analysis of Hybrid PV/Diesel/ESS in Ship Power System" *Inventions* 1, no. 1: 5.
https://doi.org/10.3390/inventions1010005