ABSTRACT:
The
distribution static synchronous compensator (D-STATCOM) has the characteristics
of nonlinearity, multivariable and strong coupling. Based on the analysis of
the D-STATCOM mathematical model, in order to improve the performance of the
linear active disturbance rejection controller (LADRC), solve the coupling
problem between the d-axis and q-axis current and improve the dynamic tracking
response speed and anti-interference ability. A controller with LADRC that
compensates the error of the total disturbance is proposed, and the stability
of the improved first-order LADRC is proved by the Lyapunov stability theory. Then
the output of the full interference channel is corrected to improve the
anti-interference ability of the system and the interference observation
ability of the linear extended state observer (LESO) to high frequency noise.
Through the analysis of the Bode diagram in the frequency domain, compared with
the traditional LADRC, the improved LADRC proposed in this paper has better
anti-interference performance. Finally, the improved first-order LADRC is used
to replace the traditional D-STATCOM control strategy for current inner loop
control, which effectively reduces the disturbance observation error of LESO.
The experimental results show that the improved LADRC control performance is
better than the proportional integral (PI) controller, and it has better
tracking performance and anti-interference performance.
KEYWORDS:
1.
Distribution
static synchronous compensator (D-STATCOM)
2.
Total
disturbance
3.
Linear active disturbance rejection control
(LADRC)
4.
Linear extended
state observer (LESO)
5.
Anti-interference
performance.
SOFTWARE: MATLAB/SIMULINK
CIRCUIT DIAGRAM:
Figure 1. Overall Control
Structure Of Voltage Type D-Statcom Device.
EXPECTED SIMULATION RESULTS:
Figure 2. Comparison Of
Reactive Current Tracking Curves Under The Control Of Pi And Improved Ladrc
Under Low Voltage Ride-Through.
Figure 3.Comparison Of
Reactive Current Tracking Under Pi And Improved Ladrc Control With Increasing
And Decreasing Load.
Figure 5. Comparison
Of Reactive Power And Active Power Under Pi And Improved Ladrc Control With
Increasing And Decreasing Load.
CONCLUSION:
Aiming at the nonlinear, multivariable and strong coupling characteristics of D-STATCOM, this paper proposes an improved first-order LADRC for the internal current loop of the D-STATCOM system. The key to LADRC performance is whether the extended state observer can accurately estimate the state variables of the system. The innovation of this paper is to propose a linear active disturbance rejection controller that compensates the total disturbance error to improve the control performance of the entire control system. And through the rigorous mathematical derivation of the Lyapunov stability theory, the stability of the improved first-order LADRC is proved, and the asymptotic stability conditions are given. Then correct the output of the total disturbance channel. Finally, the experiment proved the correctness and feasibility of the improved first-order LADRC. In addition, this article only considers the situation of balanced load and symmetrical grid voltage failure. Future work will focus on the study of the D-STATCOM control method of the LADRC under unbalanced load and distorted grid voltage.
REFERENCES:
[2]
S. R. Marjani, V. Talavat, and S. Galvani, ``Optimal allocation of DSTATCOM and
recon_guration in radial distribution network using MOPSOalgorithm in TOPSIS
framework,'' Int. Trans. Electr. Energy Syst., vol. 29, no. 2, p. e2723,
2019.
[3]
S. Rezaeian-Marjani, S. Galvani, V. Talavat, and M. Farhadi-Kangarlu, ``Optimal
allocation of D-STATCOM in distribution networks including correlated renewable
energy sources,'' Int. J. Electr. Power Energy Syst., vol. 122, Nov. 2020,
Art. no. 106178.
[4]
R. O. de Sousa, A. F. Cupertino, L. M. F. Morais, and H. A. Pereira, ``Minimum
voltage control for reliability improvement in modular multilevel cascade
converters-based STATCOM,'' Microelectron. Rel., vol. 110, Jul. 2020,
Art. no. 113693.
[5]
W. Xiao, J. Li, and Y. Wang, ``Study on reactive power compensation strategy
based on STATCOM,'' Power Capacitor Reactive Power Com- pensation, vol.
40, no. 6, pp. 24_29, 2019.
