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The existing literature primarily focuses on the utilization of CDC methodology with PI and SM controllers. The adoption of these approaches poses a potential operational failure risk in the proposed configuration, particularly when dealing with abrupt load changes in power-sharing scenarios. Furthermore, the tuning of conventional PI and SM controllers is challenging due to their non-knowledge-based nature. Moreover, the settling time required to reach a constant value is lengthier compared to controllers grounded in artificial intelligence. The suggested SBS-PCI configuration comprises two VSIs connected in parallel, sharing a common load integrated into a microgrid, which combines SPV and BESS, as given in figure 1, The parallel connection of SPV with a DC-to-DC boost converter (BC) and BESS with a DC-to-DC _ buck-boost converter (BBC) is connected across the inverter input terminals. Additionally, the battery is designed to maintain power management. Various loads are chosen for testing the performance of this configuration. The SPV and BESS enhance the PCI's DC link via BC and BBC, ensuring constant voltage

Figure 1 The existing literature primarily focuses on the utilization of CDC methodology with PI and SM controllers. The adoption of these approaches poses a potential operational failure risk in the proposed configuration, particularly when dealing with abrupt load changes in power-sharing scenarios. Furthermore, the tuning of conventional PI and SM controllers is challenging due to their non-knowledge-based nature. Moreover, the settling time required to reach a constant value is lengthier compared to controllers grounded in artificial intelligence. The suggested SBS-PCI configuration comprises two VSIs connected in parallel, sharing a common load integrated into a microgrid, which combines SPV and BESS, as given in figure 1, The parallel connection of SPV with a DC-to-DC boost converter (BC) and BESS with a DC-to-DC _ buck-boost converter (BBC) is connected across the inverter input terminals. Additionally, the battery is designed to maintain power management. Various loads are chosen for testing the performance of this configuration. The SPV and BESS enhance the PCI's DC link via BC and BBC, ensuring constant voltage

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Table I. SPV and Bess Specifications
Table I. SPV and Bess Specifications
The BESS is comprised of a battery and a BBC, accountable for regulating the Vac, as depicted in figure 3. The state of charge (SoC) is determined by eg. (7). The battery operates in dual phases: charging and discharging, depending on solar power generation. Its functionality is dictated by energy constraints, specifically the SoC limits outlined in eq. (8).
The BESS is comprised of a battery and a BBC, accountable for regulating the Vac, as depicted in figure 3. The state of charge (SoC) is determined by eg. (7). The battery operates in dual phases: charging and discharging, depending on solar power generation. Its functionality is dictated by energy constraints, specifically the SoC limits outlined in eq. (8).
2.2.2 Battery Modeling Y Py me L : Where, ?V™X and ~ ?Y ™ax are the values of maximum output voltage and current PV panel.
2.2.2 Battery Modeling Y Py me L : Where, ?V™X and ~ ?Y ™ax are the values of maximum output voltage and current PV panel.
3.1.1 Selection of droop coefficients Where m and n are the inverter droop coefficients for frequency and voltage, respectively; P* and Q* are the nominal real and reactive powers; the rated voltage is denoted by E*, and the nominal angular frequency is w*. Figure 4 displays the block diagram of DCT and figure 5 shows the graphical representation of droop characteristics respectively. Where, A@®max and AV max are decided based on the maximum d t d r affect the po coefficients droop contro. eviations a hem would roop contro eactive power when there are fluctuations in frequency and voltage due to load changes in the micro grid. An enhanced lowed in the load. The droop coefficients wil wer sharing among inverters, where larger droop ead to better power sharing. However, increasing ead to instability in the system. This conventiona method fails to achieve precise sharing of real and method is suggested to address this issue.
3.1.1 Selection of droop coefficients Where m and n are the inverter droop coefficients for frequency and voltage, respectively; P* and Q* are the nominal real and reactive powers; the rated voltage is denoted by E*, and the nominal angular frequency is w*. Figure 4 displays the block diagram of DCT and figure 5 shows the graphical representation of droop characteristics respectively. Where, A@®max and AV max are decided based on the maximum d t d r affect the po coefficients droop contro. eviations a hem would roop contro eactive power when there are fluctuations in frequency and voltage due to load changes in the micro grid. An enhanced lowed in the load. The droop coefficients wil wer sharing among inverters, where larger droop ead to better power sharing. However, increasing ead to instability in the system. This conventiona method fails to achieve precise sharing of real and method is suggested to address this issue.
Figure 7. Block diagram for EDCT From eq. (17), For acquiring @ = *, the d@ must be equal to m(P*-P-a). Thus, d@ is modified so that in the steady state, da= m(P*-Pcat). To achieve this, 6@ is reformed as:
Figure 7. Block diagram for EDCT From eq. (17), For acquiring @ = *, the d@ must be equal to m(P*-P-a). Thus, d@ is modified so that in the steady state, da= m(P*-Pcat). To achieve this, 6@ is reformed as:
introduced. Figure 6 illustrates this situation for two inverters arranged in a back-to-back configuration, with the droop curves connected. Here, points 'a' and 'a" represent the state before the load variation, maintaining the rated operating frequency w*. As the load changes from P; to P;’, the operating points shift from 'b' to 'b", indicating a reduced operating frequency. To ensure a consistent frequency and accurate active power, it is crucial to uniformly elevate the droop characteristics between the inverters until they intersect at points 'c' and 'c". This process is called the FRS and it is used to bring the frequency back to its specified nominal value, w*, by integrating the 5@ term into eq. (13) for adjustment. Figure. 6 Droop curves adjustments for real power sharing among the inverters
introduced. Figure 6 illustrates this situation for two inverters arranged in a back-to-back configuration, with the droop curves connected. Here, points 'a' and 'a" represent the state before the load variation, maintaining the rated operating frequency w*. As the load changes from P; to P;’, the operating points shift from 'b' to 'b", indicating a reduced operating frequency. To ensure a consistent frequency and accurate active power, it is crucial to uniformly elevate the droop characteristics between the inverters until they intersect at points 'c' and 'c". This process is called the FRS and it is used to bring the frequency back to its specified nominal value, w*, by integrating the 5@ term into eq. (13) for adjustment. Figure. 6 Droop curves adjustments for real power sharing among the inverters
Table II. Ratings of the Developed System 3.3 Fuzzy Controller
Table II. Ratings of the Developed System 3.3 Fuzzy Controller
current before filter, and i“, i’1qare the inverter reference output currents before the filter. DCT, as it is not changing. However, variations arise when there is a difference in line impedances of two inverters or the addition of local loads. In the proposed configuration, the impedances of the two inverters are assumed to be equal, and no local loads are present. Consequently, reactive power sharing is exclusively conducted through the DCT method. Accurate frequency restoration without errors necessitates the uniform distribution of d@ among all VSIs. To achieve this, the FRS must be simultaneously integrated into two inverters. The vertical displacement value of each VSI, denoted as do, is determined by the integral of Aw, as illustrated in figure 7. Reactive power distribution among the inverters is achieved via
current before filter, and i“, i’1qare the inverter reference output currents before the filter. DCT, as it is not changing. However, variations arise when there is a difference in line impedances of two inverters or the addition of local loads. In the proposed configuration, the impedances of the two inverters are assumed to be equal, and no local loads are present. Consequently, reactive power sharing is exclusively conducted through the DCT method. Accurate frequency restoration without errors necessitates the uniform distribution of d@ among all VSIs. To achieve this, the FRS must be simultaneously integrated into two inverters. The vertical displacement value of each VSI, denoted as do, is determined by the integral of Aw, as illustrated in figure 7. Reactive power distribution among the inverters is achieved via
Table III. MSF for DC Link Voltage :4, RESULTS AND DISCUSSION Figure 12. Msf of Output The proposed SBS-PCI was developed in MATLAB Simulink environment. To analyze the performance of the suggested method, two case studies are considered with two different loads and it is illustrated in table IV. The inverter! and inverter2 output voltage/current, voltage and current at the load terminals and active/reactive power sharing were analyzed. In addition, the THD was obtained for the proposed system, and further, it is compared with the PI controller, as illustrated in table V.
Table III. MSF for DC Link Voltage :4, RESULTS AND DISCUSSION Figure 12. Msf of Output The proposed SBS-PCI was developed in MATLAB Simulink environment. To analyze the performance of the suggested method, two case studies are considered with two different loads and it is illustrated in table IV. The inverter! and inverter2 output voltage/current, voltage and current at the load terminals and active/reactive power sharing were analyzed. In addition, the THD was obtained for the proposed system, and further, it is compared with the PI controller, as illustrated in table V.
correlations. The inference engine employs the rule base and Msf to ascertain suitable actions. Ultimately, the defuzzifier converts fuzzy variables into precise outputs. The outline of the FLCs process is illustrated in figure 9. Fuzzification is the first layer, and its outputs are fuzzy MSF, which are determined by eg. (2/).
correlations. The inference engine employs the rule base and Msf to ascertain suitable actions. Ultimately, the defuzzifier converts fuzzy variables into precise outputs. The outline of the FLCs process is illustrated in figure 9. Fuzzification is the first layer, and its outputs are fuzzy MSF, which are determined by eg. (2/).
Here, MAi TBI resembles the memberships received as the output from the 1“ layer. The triangular membership is shown in figure 10 and it is is expressed by eg. (22).
Here, MAi TBI resembles the memberships received as the output from the 1“ layer. The triangular membership is shown in figure 10 and it is is expressed by eg. (22).
Research Article | Volume 12, Issue 2 | Pages 329-337 | e-ISSN: 2347-470Xx HEEL EITIGQUiVViicd JUULTICN Ut Electrical and Electronics Research (IJEER)
Research Article | Volume 12, Issue 2 | Pages 329-337 | e-ISSN: 2347-470Xx HEEL EITIGQUiVViicd JUULTICN Ut Electrical and Electronics Research (IJEER)
Case 1: In this analysis, Load | is taken into consideration to evaluate the proposed technique. The output voltage/current waveforms of Inverter | and Inverter 2 are presented in figure 13(a) and 13(b), respectively. The load voltage/current waveforms are displayed in figure 13(c). Additionally, figure 13(d) provides total active and reactive powers at the load. Finally, figure 13(e) demonstrates that the suggested method achieves equal sharing of real and reactive powers between the inverters. This is accomplished through an enhanced droop control technique with FLC implementation. However, the solar power changes by varying the solar irradiation; accordingly, the battery will charge and discharge to maintain the constant power at load, as shown in figure 13(f). This figure clearly shows that the suggested FLC controller maintains the DCL voltage is constant with low settling time even under transient conditions such as variations in solar irradiation as compared to the PIC and SMC.
Case 1: In this analysis, Load | is taken into consideration to evaluate the proposed technique. The output voltage/current waveforms of Inverter | and Inverter 2 are presented in figure 13(a) and 13(b), respectively. The load voltage/current waveforms are displayed in figure 13(c). Additionally, figure 13(d) provides total active and reactive powers at the load. Finally, figure 13(e) demonstrates that the suggested method achieves equal sharing of real and reactive powers between the inverters. This is accomplished through an enhanced droop control technique with FLC implementation. However, the solar power changes by varying the solar irradiation; accordingly, the battery will charge and discharge to maintain the constant power at load, as shown in figure 13(f). This figure clearly shows that the suggested FLC controller maintains the DCL voltage is constant with low settling time even under transient conditions such as variations in solar irradiation as compared to the PIC and SMC.
Figure 13. (a) V/I waveforms of inverter 1 (b) V/I of inverter 2 (c) Voltage and current waveforms at load (d) Total active and reactive power waveforms (e) Active and reactive power sharing waveforms (e) Solar power, battery power with variable irradiation and constant DCL voltage and load power of 8 kW
Figure 13. (a) V/I waveforms of inverter 1 (b) V/I of inverter 2 (c) Voltage and current waveforms at load (d) Total active and reactive power waveforms (e) Active and reactive power sharing waveforms (e) Solar power, battery power with variable irradiation and constant DCL voltage and load power of 8 kW
Figure 14. (a) Load V & I waveforms, (b) Total active and reactive power waveforms (c) Active and Reactive power sharing waveforms (d) Solar power, battery power, voltage at DC link and load power with variable irradiation and constant temperature Case 2: The superior performance of the developed method is demonstrated by considering the combination of Load | and Load 2. Figure 14(a) displays the output voltage/current waveforms. This figure shows that the load current increases from 20A to 30A as the load changes from 5kW to 15kW.
Figure 14. (a) Load V & I waveforms, (b) Total active and reactive power waveforms (c) Active and Reactive power sharing waveforms (d) Solar power, battery power, voltage at DC link and load power with variable irradiation and constant temperature Case 2: The superior performance of the developed method is demonstrated by considering the combination of Load | and Load 2. Figure 14(a) displays the output voltage/current waveforms. This figure shows that the load current increases from 20A to 30A as the load changes from 5kW to 15kW.
Figure 14(b) gives total active and reactive power available at the load. The proposed controller effectively ensures equal control of active and reactive powers among the inverters using the proposed technique, even when there is a load change at t=0.5 sec. This is evident in figure 14(c). However, with variable solar irradiation, the solar power undergoes changes, leading to corresponding charging and discharging of the battery to sustain a consistent power supply to the load, as depicted in figure 14(d). This figure distinctly illustrates that the suggested FLC effectively maintains a consistent DCL voltage even in the presence of variations in solar irradiation. Furthermore, the proposed system frequency is maintained as constant, as shown in figure 15. The harmonic distortion for two cases was obtained and exhibited in figure 16. This study focused on the operation and control of a solar battery integrated Parallel Connected Inverter (SBS-PCI). An EDCT technique along with the FLC was proposed to address the uniform distribution of power during load change over the conventional droop control technique, and it was compared with
Figure 14(b) gives total active and reactive power available at the load. The proposed controller effectively ensures equal control of active and reactive powers among the inverters using the proposed technique, even when there is a load change at t=0.5 sec. This is evident in figure 14(c). However, with variable solar irradiation, the solar power undergoes changes, leading to corresponding charging and discharging of the battery to sustain a consistent power supply to the load, as depicted in figure 14(d). This figure distinctly illustrates that the suggested FLC effectively maintains a consistent DCL voltage even in the presence of variations in solar irradiation. Furthermore, the proposed system frequency is maintained as constant, as shown in figure 15. The harmonic distortion for two cases was obtained and exhibited in figure 16. This study focused on the operation and control of a solar battery integrated Parallel Connected Inverter (SBS-PCI). An EDCT technique along with the FLC was proposed to address the uniform distribution of power during load change over the conventional droop control technique, and it was compared with
Related topics:
total harmonic distortion (THD)Power SharingSPV System DesignParallel InvertersFuzzy Logic Controller (FLC)
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