Harmonic Mitigation in a Grid Connected PV Wind System Using DSTATCOM
 
Harmonic Mitigation in a Grid Connected PV Wind System Using DSTATCOM is a MATLAB/Simulink-based simulation model developed to study renewable energy integration, power-quality improvement, and harmonic compensation in a three-phase distribution network.
 
The system combines solar photovoltaic generation, wind energy conversion, grid supply, nonlinear/lagging loads, and a DSTATCOM at the point of common coupling. The DSTATCOM operates as a shunt-connected compensator and injects the required compensating current to improve source-current waveform quality, support reactive-power compensation, and maintain stable grid operation under changing renewable-generation conditions.
 
The model incorporates synchronous reference frame (dq) control, PI regulators, reference-current generation, PWM-based voltage-source inverter control, and DC-link voltage regulation. The PV and wind sources are subjected to variations in solar irradiation and wind speed to evaluate the dynamic behavior of the hybrid renewable system.
 
Simulation results demonstrate effective current compensation and grid-support capability. FFT analysis of the compensated grid current gives a Total Harmonic Distortion (THD) of 1.36%, with a 50 Hz fundamental component magnitude of 57.84, demonstrating good harmonic performance and compliance with commonly accepted power-quality limits.
 
Specifications
 
Simulation Platform: MATLAB/Simulink
System Type: Three-phase grid-connected hybrid renewable energy system
Renewable Sources: Solar PV and wind energy conversion system
Compensation Device: DSTATCOM
DSTATCOM Topology: Shunt-connected voltage-source inverter
Control Method: Synchronous Reference Frame (SRF/dq) control
Grid Frequency: 50 Hz
Grid Voltage Class: Approximately 400 V
DSTATCOM DC-Link Reference: 1000 V
PI Controller Gain: (K_p = 800)
PI Integral Gain: (K_i = 1200)
Load Type: Nonlinear and lagging three-phase load
PV Input Variation: Variable solar irradiation
Wind Input Variation: Variable wind speed
DSTATCOM Switching: PWM-controlled VSI
Fundamental Frequency for FFT: 50 Hz
Fundamental Magnitude: 57.84
Grid-Current THD: 1.36%
Major Simulation Events:
DSTATCOM enabled at approximately 0.10 s
Wind-speed reduction at approximately 0.20 s
PV irradiation reduction at approximately 0.30 s
 
Working
 
The hybrid system connects the PV source, wind generation system, utility grid, loads, and DSTATCOM through a common AC distribution bus.
 
The PV subsystem converts incident solar energy into electrical power. Changes in solar irradiation directly influence the available PV output. Similarly, the wind-energy subsystem converts mechanical wind energy into electrical power, and its generated output varies according to wind-speed conditions.
 
The utility grid maintains overall supply-demand balance whenever renewable generation is insufficient or varies dynamically.
 
The connected nonlinear and lagging loads draw distorted and reactive currents. Without compensation, these currents can increase current harmonics, reactive-power demand, and losses in the distribution network.
 
To overcome this problem, the DSTATCOM continuously measures three-phase voltages and currents at the point of common coupling. The measured quantities are transformed from the (abc) reference frame into the synchronous (dq) frame.
 
The DC-link voltage is compared with its reference value:
[
e_{dc}=V_{dc}^{*}-V_{dc}
]
The PI controller processes this voltage error and generates the active-current component required to maintain the DC-link voltage:
[
i_d^{*}=K_p e_{dc}+K_i\int e_{dc},dt
]
The reactive-current reference is selected according to the required compensation objective. The resulting (dq)-axis reference currents are transformed back into three-phase reference currents.
The actual source currents are then compared with these reference values. PWM switching signals are generated for the DSTATCOM voltage-source inverter, allowing it to inject compensating currents into the grid.
 
When the DSTATCOM is activated, the compensator supplies the required reactive and harmonic components of load current. Consequently, the grid mainly supplies the fundamental active-current component.
 
During reduction in wind speed or PV irradiation, renewable generation decreases and the utility grid automatically supplies a larger portion of the required power. The DSTATCOM continues regulating current quality during these operating transitions.
 
The resulting compensated grid-current spectrum shows a THD of only 1.36%, confirming effective harmonic mitigation.
 
Use Cases
 
1. Renewable Energy Integration Research
Suitable for studying simultaneous integration of solar PV and wind energy into a three-phase utility network.
2. Harmonic Mitigation Studies
Useful for investigating harmonic currents produced by nonlinear loads and evaluating DSTATCOM-based compensation.
3. Power-Quality Improvement
Can be used to analyze source-current quality, reactive-power compensation, voltage regulation, and distortion reduction.
4. DSTATCOM Control Development
Provides a platform for implementing and comparing SRF, PI, fuzzy logic, neural-network, sliding-mode, or advanced predictive DSTATCOM controllers.
5. PV and Wind Variability Analysis
Useful for evaluating grid behavior during sudden changes in solar irradiation and wind speed.
6. Academic Projects and Research
Applicable to B.E./B.Tech., M.E./M.Tech., Ph.D., and research projects related to power electronics, renewable energy, smart grids, microgrids, and power quality.
7. Controller Performance Evaluation
Enables investigation of DC-link regulation, transient response, current tracking, dynamic power sharing, and harmonic compensation.
8. FFT and THD Analysis
The model can be used to perform frequency-spectrum analysis and determine harmonic distortion before and after compensation.
9. Advanced Research Extension
The existing model can be extended with battery energy storage, EV charging, STATCOM optimization, AI-based control, adaptive control, grid faults, voltage sag/swell compensation, or hardware-in-the-loop validation.