Current Sensor-Less Virtual Synchronous Generator Model Predictive Control Based on Sliding Mode Observer

Yanyan Li,Leilei Guo,Nan Jin,Falong Lu,Weitao Li

doi:10.1109/access.2021.3053587

Yanyan Li, Leilei Guo + Show 3 more

Open Access

https://doi.org/10.1109/access.2021.3053587

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Journal: IEEE Access	Publication Date: Jan 1, 2021
Citations: 29	License type: CC BY 4.0

Affiliation: Zhengzhou University of Light Industry

Abstract

In recent years, virtual synchronous generator (VSG) control algorithm has been widely studied in distributed grid-connected power inverters to deal with active and reactive power adjustment by simulating the operation principle of the actual synchronous generator. Nevertheless, once the current sensor fails, the grid-connected power inverter will lose its stability. To enhance the fault-tolerant operation ability of the grid-connected power inverter, a new inverter side current sensor-less model predictive control method based on sliding mode observer (SMO) is proposed. The stability of the SMO is analyzed by using the Lyapunov stability criterion. The gains of the SMO are then designed by analyzing their influences on the current and voltage observation based on the closed-loop transfer functions. Besides, to show the influences of the capacitance changes on the current observation, a detailed parameter sensitivity analysis is also carried out. Then, by using the estimated inductance current from the SMO, a current sensor-less model predictive control method is finally proposed. The main novelty of the proposed method is that both the output voltage of the inverter and the inverter side inductance are not required in the proposed SMO. So, the accuracy of current sensor-less control is improved. To verify the effectiveness of the proposed method, detailed experimental studies are carried out based on a Typhoon and PE-Expert 4 based experimental platform.

Highlights

When the conventional power electronic conversion interface is connected to the grid, the power system is affected by the power fluctuations and faults due to the lack of inertia and damping [1]
This paper proposes an improved inverter side current sensor-less model predictive control (MPC) method for virtual synchronous generator (VSG) based a novel sliding mode observer (SMO), which observes the inverter side current using the sampled capacitor voltage and grid current
This paper proposes an inverter side current sensor-less control method for VSG, which ensures the stable operation after current sensor fails

Summary

INTRODUCTION

When the conventional power electronic conversion interface is connected to the grid, the power system is affected by the power fluctuations and faults due to the lack of inertia and damping [1]. This paper proposes an improved inverter side current sensor-less MPC method for VSG based a novel sliding mode observer (SMO), which observes the inverter side current using the sampled capacitor voltage and grid current. The novelty of this method is that only the information of the filter capacitance is required. The proposed scheme contains three parts: a) an inverter side current observer, which is used to estimate the current and remove the current sensors, b) an improved MPC using the estimated current, which can be used to ensure the steady operation of the VSG under current sensor failure condition, c) an outer power loop, which is used to simulate an actual SG. INDUCTOR CURRENT OBSERVER DESIGN The proposed observer in paper [31] is designed as dif αβ dt

C if αβ

CAPACITANCE ERROR ANALYSIS

HIL EXPERIMENT VALIDATION

DISCUSSION AND CONCLUSION