FOPID controlled PV based QBC fed gamma Z-source inverter applicable for pump operations in an induction motor drive

ABSTRACT


INTRODUCTION
The induction motor is popular for variable speed applications because it is more cost-efficient.The voltage rating of induction motor does not match with the voltage rating of PV.Hence a boost converter may be used between PV and induction motor.Various controllers with different modes of control have been taken into study and the summarizations of all those research results were compared and the net outcomes were shortlisted here.The hysteresis and PI current controllers, which control the load current, have problems with current ripple and phase lag, respectively.
The above problems are successfully handled by the suggested predictive current control technique [1].Reduced steady state error and improved time domain responsiveness are two advantages of the FLC controlled cascaded fly back converter (CFLB) technology [2].Utilizing the MATLAB-Simulink platform and the new European driving cycle (NEDC) test, the suggested controller's speed tracking capability is evaluated."When compared to fuzzy FOPID controllers based on the genetic algorithm (GA) and particle swarm optimization (PSO), the suggested controller provides the best performance for speed tracking" in [3].The use of n-conventional converters is one possible solution to this problem; however, the complex control circuitry is required.An n-stage cascade converter in addition to a single active switch is an alternative solution [4].A fuel-cell stack is modeled using electrical parameters.After that, the model is combined with a high stepup voltage converter model to create an integrated model that takes the behavior of the fuel-cell stack into account in [5]."The suggested controller's inner loop is established on sliding-mode control, with a sliding surface established for the input inductor current.In an outer loop, a proportional-integral (PI) compensator that acts across the output voltage error adjusts the current reference value of the sliding surface obtained" in [6].The MATLAB state flow toolbox and an NI data collecting system are used in the actual development of FOPID and IOPID controllers.The FOPID controller has improved performance and robust stability against the experiment variables, according to the results of the robustness study in [7].While offering the same voltage boost, it may significantly reduce Z-source capacitor voltage stress and has an internal restriction on inrush current at startup [8].It provides a larger boost capability, a broader input/output voltage range, and softswitching capabilities without the use of extra components [9].A Z-source inverter system implemented in [10].Diode front ends are equipped with a tiny capacitor on the AC side and a unique LC network in the DC-link.
The current study aims to improve the dynamic responsiveness of the LCMI system by using an HC controller.As a result of the proposed LCMI system [11], a high voltage gain and enhanced time responsiveness can be achieved.In this study, we present a novel H10 inverter scheme for 2-level, 3-phase inverter applications.In the proposed architecture, CMV can be constant or zero without additional passive components [12].An inverter built around a Z-source inverter (ZSI) with a grid-connected wind power production system.Based on the analysis of ZSI operation, a system for double closed-loop control is proposed [13].To increase the controller's capabilities, a discrete-time model is implemented using the MPC technique.Using the controller, each phase current can be managed separately, enhancing system flexibility [14].A hybrid model can be utilized as a numerical simulator for multi-source renewable energy systems (MS-RES).The model is simple and low-cost tool for constructing, validating, and assessing the outcomes of control techniques designed for energy transfer optimization in [15].A linked transformer and fewer components are required for the proposed inverters when compared to existing topologies [16].There is a double-frequency power imbalance between the dc input and ac output in single-phase photovoltaic (PV) systems.The passive network must buffer the energy of the double-frequency ripple (DFR).The suggested control method can greatly lower the capacitance required and produce low input voltage DFR without the use of any additional hardware components [17].Adaptive control of ZSI is illustrated in [18].A charging/discharging system that consists of a Cuk converter and a new controller to adjust the voltage of a dc-bus, The Cuk converter ensures system stability and rapid dynamic response for all working circumstances, while the controller ensures constant currents for the battery and dc-bus [19].SM controllers provide higher transient performance than both regular PIDs and fractional-order PIDs (FOPIDs).In order to assess the efficiency of the SM controller, different timedomain criteria were used [20].The inner loop of the suggested method is determined by the input inductor current control.The sliding manifold's reference signal is modified via an outside loop that regulates the output current.The Routh-Hurwitz criteria and the analogous control technique are used to determine the stability of two-loop controllers [21].Protecting three-phase induction motors operating in single-phase mode is the focus of this dissertation using microcontrollers, GSM modules, step-down transformers, and protective relays [22].A method for grid-connected cascaded multilevel 3-phase inverters that uses fuzzy logic.Current controllers and carriers used for traditional modulation have been totally eliminated by this approach [23].Speed controller of 3 IM without PWM technology was used to evaluate the performance of the recommended controller under both constant and changing load conditions [24].The suggested optimal PI and the regular PID are used to manage how the second DC-DC converter is used for battery charging [25].This work aims to identify combination of suitable boost converter and inverter for induction motor fed pumps.This work also tries to improve the dynamic response of PV-QBC-GZSI-IMS.
The methodology flow chart is shown in Figure 1.Research problem is formulated based on literature survey on IM drives.After selecting converter and inverter, design calculations are made.Simulation of closed loop PV-QBC-GZSI-IMS with PI and FOPID are performed to identify better controller in closed loop.Comparison of related literature [10], [11] and proposed work on IMS is given in Table 1.The overview of this complete literature does not deal with PV-QBC-GZSI-IMS.This research suggests combination of QBC & GZSI to control IMS.The above literatures do not report the speed regulation of PV-QBC-GZSI-IMS using CM-FOPID controller.This work proposes CM-FOPID to control QBC-GZSI-IMS.
Our paper focuses on the identification of a non-isolated high gain DC-DC converter that has high voltage gain, a wide range of operation, and reduced input current ripples suitable for induction motor drive.Section 2 gives an overview of quadratic boost converter.Section 3 presents analysis of QBC-GZSI, section 4 gives description of QBC-GZSIS, section 5 provides simulation studies and comprehensive comparison of the simulation with PI and FOPID controllers, section 6 includes conclusion and future scope of work.

QUADRATIC BOOST CONVERTER -AN OVERVIEW
A quadratic boost converter is a DC-DC boost converter with a second phase that boosts DC voltage.A quadratic boost converter output voltage is always larger than the input voltage.The output voltage may be calculated using the (1).
MOSFETs (Q) serve as switches, while inductors (L), diodes (D), capacitors (C), and resistors (R) serve as loads in the quadratic boost converter (QBC) circuit depicted in Figure 2. The circuit will operate based on the assumption.If the switch is in ideal the capacitors C1 & C2 are considered to be large value and the voltage on the capacitors VC1 and VC2 is approximately stable throughout the switching process.
The (2) is used to calculate the gate current in the MOSFET, where PG is the power at the gate, VGS is the voltage at the input (VG) multiplied by the duty cycle %.(D). Where

DESCRIPTION OF PROPOSED METHOD
Output of PV is used to charge the battery.Constant voltage from battery is stepped-up using QBC.The output of QBC is inverted and applied to 5HP-IM.Control unit of GZSI-IM is used to apply pulses to QBC & GZSI.Block structure of closed loop PV-QBC-GZSI-IMS using CM-PI and CM-FOPID-controller is delineated in Figure 5. Speed of 3 phase induction motor is sensed then it is compared with the reference speed to obtain speed error (SE).The SE is applied to speed PI/FOPID-1.The output of PI/FOPID-1 is compared with actual current and error is applied to PI/FOPID-2.The output updates the duty cycle of the QBC.

FOPID Controller
Academics and industry have both been interested in FOPID controllers in recent years.In fact, they are more versatile than ordinary PID controllers (since they have five parameters to choose from), because they have five parameters to choose from.This may, however, make tuning the controller more difficult.

Design considerations
The following assumptions were made to design QBC-GZSI-IMS is given in Table 2. From   =   (1−) 2 , D works out to 0.65.TON works out to 0.13 ms and TOFF works out to 0.07 ms.L=

SIMULATION RESULTS
Closed loop simulation of CM-PI and CM-FOPID controlled PV based QBC fed GZSI with induction motor in the MATLAB/Simulink is performed.The results are compared in terms of time domain parameters of speed in QBC-GZSI-IM.A better controller for QBC-ZSI-IM system is identified based on simulation results.Speed and torque response are obtained for a step change in input voltage using current-mode PI and FOPID controllers.

Closed loop CM-PI control PV based QBC fed GZSI with induction motor
The circuit diagram of Closed-loop-CM-PI control PV-QBC-GZSI-IMS is delineated in Figure 6.Speed signal is sensed then it is compared with reference speed.The SE is given to PI-1.Output of PI-1 is compared with current signal and CE is applied to PI-2.The output of PI-2 is used to update duty ratio of MOSFET in QBC.Triggering pulses of inverter, line voltage of motor, speed, torque and mechanical power are measured using scopes.Input-voltage of closed-loop-CM-PI control PV-QBC-GZSI-IMS is represented in Figure 7 and its value is 74 V.A source disturbance of 20% is applied at t = 3.2 secs.

Closed loop CM-FOPID control PV based QBC fed GZSI with induction motor
The time response of PV-QBC-GZSI-IMS with CM-PI is sluggish.Hence it is proposed to control PV-QBC-GZSI-IMS using CM-FOPID controller.The circuit diagram of Closed-loop-CM-FOPID control PV-QBC-GZSI-IMS is delineated in Figure 8. Scopes are connected to display switching pulses, output of QBC, speed of IMS and torque of IMS.
Comparison curves for motor speed of Closed-loop-PV-QBC-GZSI-IMS is with CM-PI and CM-FOPID is delineated in Figure 9.The speed of PV-QBC-GZSI-IMS settles after few oscillations.Torqueresponse of Closed-loop-CM-PI and CM-FOPID control PV-QBC-GZSI-IMS is delineated in Figure 10.The torque of IMS settles without any oscillations.The motor speed with CM-FOPID is found to be less than that of CM-PI controlled PV-QBC-GZSI-IMS.The torque with CM-PI is higher than that of CM-FOPID controlled PV-QBC-GZSI-IMS.

Comparison of time domain parameters of CM-PI and CM-FOPID control PV-QBC-GZSI-IMS
Table 3 outlines the time domain parameters for speed of 1300 RPM using CM-PI and CM-FOPID controller.By using CM-FOPID controller, rise-time is dwindled from 3.28 sec to 3.27 sec, peak-time is dwindled from 3.46 sec to 3.38 sec, settling-time is dwindled from 3.68 sec to 3.56 sec, steady-state-error is dwindled from 3.98 RPM to 2.85 RPM.Table 4 outlines the time domain parameters for torque with reference speed of 1300 RPM using CM-PI and CM-FOPID controller.By using CM-FOPID controller, rise-time is dwindled from 3.39 sec to 3.37 sec, peak-time is dwindled from 3.48 sec to 3.45 sec, settling-time is dwindled from 3.89 sec to 3.76 sec, steady-state-error is dwindled from 0.76 to 0.65 N-m.
Table 5 outlines the time domain parameters for speed of 1350 RPM using CM-PI and CM-FOPID controller.By using CM-FOPID controller, rise-time is dwindled from 3.27 sec to 3.26 sec, peak-time is  6 outlines the time domain parameters for torque with reference speed of 1350 RPM using CM-PI and CM-FOPID controller.By using CM-FOPID controller, rise-time is dwindled from 3.38 sec to 3.36 sec, peak-time is dwindled from 3.45 sec to 3.40 sec, settling-time is dwindled from 3.83 sec to 3.71 sec, Steady-state-error is dwindled from 0.70 to 0.61 N-m.
Table 7 outlines the time domain parameters for speed of 1400 RPM using CM-PI and CM-FOPID controller.By using CM-FOPID controller, rise-time is dwindled from 3.25 sec to 3.24 sec, peak-time is dwindled from 3.38 sec to 3.29 sec, settling-time is dwindled from 3.57 sec to 3.45 sec, steady-state-error is dwindled from 3.62 RPM to 2.76 RPM.Table 8 outlines the time domain parameters for torque with reference speed of 1400 RPM using CM-PI and CM-FOPID controller.By using CM-FOPID controller, rise-time is dwindled from 3.35 Sec to 3.33 sec, peak-time is dwindled from 3.39 sec to 3.37 sec, settling-time is dwindled from 3.75 sec to 3.69 sec and steady-state-error is dwindled from 0.68 to 0.52 N-m.
By using CM-FOPID (motor speed), rise-time, peak-time and steady-state-error are reduced.By using CM-FOPID (motor torque), rise-time, peak-time and steady-state-error are also reduced.Hence, the outcome indicates that the closed loop PV-QBC-GZSI-IMS with CM-FOPID is superior to closed loop PV-QBC-GZSI-IMS with CM-PI controller.

CONCLUSION
This paper has analyzed closed loop QBC-GZSIS.It is suitable for induction motor drive that integrates PV-system.Further, the reduced response time makes it appropriate to use it for systems with higher band-width.Combination of QBC&GZSI is proposed for control of IM.Speed regulation of closed loop-PV-QBC-GZSI-IMS for pumps with CM-PI and CM-FOPID controller are simulated with MATLAB/Simulink platform.The simulation-outcomes of Speed and torque time domain comparison in closed-loop-PV-QBC-GZSI-IMS with-CM-PI and CM-FOPID controllers are presented.By using CM-FOPID (motor speed), risetime, peak-time and steady-state-error are reduced.By using FOPIDC, settling-time of speed is reduced to 3.45 sec, steady-state-error in speed is reduced to 2.76 RPM.By using CM-FOPID, rise-time, peak-time and steadystate-error are also reduced.Hence, the outcome illustrates that the closed loop CM-FOPID controlled PV-QBC-GZSI-IMS is superior to closed loop CM-PI controller.PV-QBC-GZSI-IMS has high voltage gain and reduced ripple.Fast time response is achieved by using CMC for PV-QBC-GZSI-IMS.The drawback of PV-QBC-GZSI-IMS is that it uses large number of passive elements for QBC and GZSI.The characteristics of QBC-GZSI fed induction motor matches with the characteristics of pump.Combination of QBC-GZSI is identified as a suitable converter inverter system for induction motor drive.FOPID controlled PV-QBC-GZSI-IMS is found to have improved response compared to PI controlled PV-QBC-GZSI-IMS.The present work improves the time response of PV-QBC-GZSI-IMS using the current mode -FOPID controller.By using QBC and GZSI, we can also reduce the PV rating of the panel.
Performance of closed-loop PV-QBC-GZSI-IMS with CM-PI and CM-FOPID controller is investigated here.Closed-loop PV-QBC-GZSI-IMS with CM-PR and hysteresis controller can be done in future.Efficiency of PV-QBC-GZSI-IMS can be improved by replacing normal diodes and MOSFETs with silicon carbide devices.

Table 3 .
Comparison time domain parameters of motor speed 1300 rpm

Table 4 .
Comparison time domain parameters of motor torque for 1300 rpm

Table 5 .
Comparison time domain parameters of motor speed 1350 rpm

Table 6 .
Comparison time domain parameters of motor torque at 1350 rpm