Description:SUMMARY

[0009] The following presents a simplified summary of the disclosure in order to provide a basic understanding of the reader. This summary is not an extensive overview of the disclosure and it does not identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later.

[0010] Exemplary embodiments of the present disclosure are directed towards, a device for Control of Solar Powered Induction Motor Water Pumping System for Flow Control.

[0011] In accordance with an aspect of the present invention, the prototype model contains a three-phase induction motor, interleaved boost converter, voltage source inverter, and DSPIC microcontroller.

[0012] Generally, in one illustrative embodiment, the present invention is directed towards, MPPT (Maximum Power Point Tracking) controller algorithm is designed based on the incremental conductance method for producing reference voltage in a flexible step size.

[0013] Yet another exemplary object of the present disclosure is directed towards the configuration the of two-phase interleaved boost converter

[0014] An exemplary aspect of the present subject matter is directed towards the design of a A PI (Proportional-Integral) closed-loop controller, which is designed on a DSPIC microcontroller to regulate the speed of the induction motor

[0015] An exemplary aspect of the present subject matter is directed towards the PI controller parameters are tuned by the PSO algorithm.

Brief Description of the Drawings

[0016] In the following, numerous specific details are set forth to provide a thorough description of various embodiments. Certain embodiments may be practised without these specific details or with some variations in detail. In some instances, certain features are described in less detail so as not to obscure other aspects. The level of details associated with each of the elements or features should not be construed to qualify the novelty or importance of one feature over the others.

[0017] FIG. 1 is a The basic model of a water pumping system, in accordance with some embodiments of the present disclosure.

[0018] FIG. 2 is the Two phases interleave boost converter, to an exemplary embodiment of the present disclosure.

[0019] FIG. 3 is Flow chart of incremental conductance method, according to an exemplary embodiment of the present disclosure.

[0020] FIG. 4. Flow chart of firing pulse generation, according to an exemplary embodiment of the present disclosure.

[0021] Figure 5. Flow chart of PSO algorithm, according to an exemplary embodiment of the present disclosure.

[0022] Figure 6 Simulation diagram of closed loop induction motor, according to an exemplary embodiment of the present disclosure.

[0023] Figure 7 Hardware setup of induction motor water pumping, according to an exemplary embodiment of the present disclosure.

Detailed Description of Example Embodiments

[0024] It is to be understood that the present disclosure is not limited in its application to the details of construction and the arrangement of components outlined in the following description or illustrated in the drawings. The present disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

[0025] The use of "including", "comprising" or "having" and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The terms "a" and "an" herein do not denote a limitation of quantity, but rather denote the p resence of at least one of the referenced item. Further, the use of terms "first", "second", and "third", and the like, herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.

[0026] The induction motor is used frequently in solar water pumping systems because of its advantages such as being inexpensive, self-starting, low maintenance, and rugged. FOC (Field Oriented Control) allows the decoupling of the torque and the flux by an appropriate motion of the flux (rotor) in the reference frame of rotating. More ever, the FOC may achieve some decoupling because of the motor parameters of variable variations. The IOL (Input-Output Linearization) control provides improved performances in comparison with the basic FOC and battles parameter difference. The goal of IOL is to reach a linearization of the induction motor model employing Lie derivatives. The linearization provides full system stability and decoupling, which allows the regulation of the torque and the flux independently in the static reference frame.

[0027] The invention in its several embodiments can still include The DC-DC boost converter is used to boost the output voltage from the input voltage. But it has some drawbacks such as large current and voltage ripples, a semiconductor device having maximum stress, etc. which minimizes the efficiency and stability of the system. Multi-phasing or interleaving techniques are the solutions to answer the problems. The parallel converters elements are connected in the interleaving model. The series or parallel connection of elements is connected in this model. The performance of interleaved boost converter provides less ripple in input current and output current and output voltage. Increase efficiency, a transient response, minimum switching loss, and the filter components are smaller size. The complete system operation is improved by increasing the greater number of stages.

[0028] According to a non-limiting exemplary embodiment of the present disclosure, FIG. 1 depicts the represents the basic model of a water pumping system. The solar array feeds the DC bus through interleave boost converter. The centrifugal pump and induction motor are powered by the 3-phase inverter VSI (Voltage Source Inverter). The interleaved boost converter is utilized to produce the maximum power from the solar panel. The voltage source inverter is used to regulate the speed of the induction motor.

[0029] Further, The designed parameters and specifications of the model are represented in table-1
Table-1: The specifications of the model
parameters value

Solar array Open circuit voltage (Voc) 44.67V
Maximum power current_(Imax) 8.65A
Maximum power voltage
(Vmax) 36.42V
Maximum power (Pmax) 315W
Short circuit current (Isc) 9.15A

Induction motor drive Power 0.75 KW
Voltage 415 V
Frequency 50 HZ
Ampere 1.7 A(star)
Speed 1390 rpm
Efficiency 79.8
Power factor 0.77

[0030] According to a non-limiting exemplary embodiment of the present disclosure, FIG.2 depicts the The interleaved boost converter can be designed for n phases. Here two-phase boost converter is designed with the following parameters.
(a) Duty Cycle (D):
The input voltage and output voltage of n phases are and Vo then the calculation of the duty cycle is equal to the calculation of a normal boost converter.
V_o=V_in/((1-D)) (1)
The variation of the duty cycle from 0 to 100%, it is a ratio or percentage. In this paper, the duty cycle is varied by incremental conduction algorithm.
(b) Input Current ( I_in):
I_in=P_in/V_in (2)
Where = input current (A), Vin = input voltage (V) and
Pin = input power (W)
(c) Current Ripple of Inductor (∆I_L) :
The magnitude of the current ripple of the inductor for interleave boost converter and normal boost converter is equal.
∆I_L = (V_in.D)/(f.L) (3)
Where L=inductance (H), f=switching frequency (HZ), =input voltage, and D=duty ratio.
(d) Selection of Inductor and Capacitor:
The following equations are used to calculate the values of the inductor and capacitor.
C= (V_o.D)/(∆V_o.R.f) (4)
L= (V_in.D)/(f.∆I_L ) (5)
Where Vin =input voltage(V),
R=resistance (ohms), Vo =output voltage(V), D= duty cycle, f=frequency (Hz), = ripple voltage of capacitor, =ripple current of inductor.
(e) Selection Of Power Electronic Devices:
In this work, the switching devices are ideal MOSFET and the phase shifting angle for the two phases is 180 degrees for the two phases interleave boost converter.

[0031] Further, two control techniques are implemented to control the proposed system properly. An incremental conductance algorithm-based MPPT controller is proposed to boost the solar power and a PI controller is implemented to regulate the speed of the DC motor.

[0032] In an embodiment, Fig 3 Flow chart of incremental conductance method. For controlling the speed of the motor through the DSPIC microcontroller it requires the feedback signal and that signal is measured through a flow sensor in terms of flow rate with respect to the speed of the motor. For controlling the speed of the motor in terms of voltage or frequency through firing pulses of the three-phase MOSFET inverter and the firing pulses are generated based on the below flowchart.

[0033] In a similar embodiment, The flow sensor signal is converted into a digital signal and uses this signal as a control signal. Based on the controlling signal and reference signal written the program in the microcontroller generates the firing pulses based on the cosine scheme and that generated firing pulses send through PWM pins of DSPIC.

[0034] In accordance with a non-limiting exemplary embodiment of the present subject matter, the PI controller is used to minimize the error signal and for doing that one needs to optimize the controller parameters. Here PSO algorithm is used to optimize the controller parameters and optimization processes were done in MATLAB/Simulink environmental. In this model, initially run the motor in an open loop and note down the response for different conditions. Based on the response find out the motor parameters like armature resistance, reactance and etc. then run the motor in a closed loop in Simulink and optimize the controller parameters based on the optimization algorithm. This paper calculated the Kp and Ki values for minimum error by using the PSO algorithm.

[0035] In accordance with a non-limiting exemplary embodiment of the present subject matter,fig the The mathematical equation of the PI controller is
U(t)=k_p e(t)+k_i ∫▒〖e(t)〗 (6)
Where, e(t)=r(t)-u(t)
Apply Laplace transform the above equation
U(s)=k_p e(s)+k_i/s e(s)
(U(s))/(e(s))=k_p+k_i/s
(U(s))/(e(s))=(k_p s+k_i)/s (7)
Where; k_pis proportional gain constant, is integral gain constant.

[0036] In accordance with a non-limiting exemplary embodiment of the present subject matter, Figure 5. depicts Flow chart of PSO algorithm. In the PSO algorithm, initially set the parameters like weights, and constants and initialize the position and velocity. Update the velocity and position and find each fitness value and update the local best and global best.

[0037] In an embodiment of the present subject matter, the simulation model of the induction motor running in the closed loop condition is shown in below Fig-6. Here the solar panel generates power under different irradiation and the output of the panel is supplied to the dc bus through the interleaved boost converter. The boost converter is designed through MOSFETs, inductors, and capacitors. The input to the boost is variable and the output is constant due to the MPPT control algorithm. The boost converter response is given as an input to the 3-phase inverter and the inverter is designed by using MOSFETS. The inverter output is an input of 3 phase induction motor.

[0038] In an embodiment, the hardware setup and implementation of induction motor water flow control is shown in Fig-7. Here, the solar panel is designed by 6 solar modules connected in parallel and each solar module is connected by 12 solar cells. The interleaved boost converter is implemented and it converts the variable voltage into a constant voltage of 200V. The 3-phase inverter is implemented with MOSFETS and inverter output to the 3-phase induction motor of 0.75KW.

[0039] In an embodiment, simulation of the water pumping model has proceeded in Simulink/MATLAB atmosphere under various conditions. To observe the various operating conditions of interleaved boost converter for the irradiance is a change from minimum insolation level (200W/m2) to maximum insolation level (1000W/m2). Initially, the induction motor operates in an open loop under different speed and voltage conditions and after that, the same motor runs in closed loop condition with a controller. The simulation is designed with the prototype model.

[0040] Further, in an embodiment, induction motor feed by a solar system was represented in this paper. Initially, designed an incremental conductance method for the MPPT controller and along with designed and tested a two-phase interleaved boost converter. The closed-loop control uses a PI controller and those parameters are tuned by the PSO algorithm. The closed loop system was designed with a DSPIC microcontroller and the speed of the motor is measured in terms of flow rate. The analysis and result show that the incremental conductance-based MPPT algorithm takes the value of incremental voltage to give better performances. On the other side, the boost converter gives regulated output based on MPPT. Finally, the PI controller regulates the speed of the motor with good accuracy and fast dynamic.
, Claims:We claim

1. Design Of Control For Solar Powered Induction Motor Water Pumping System For Flow Control , comprising:
three-phase induction motor,
interleaved boost converter,
voltage source inverter, and DSPIC microcontroller;

2. Wherin the device as claimed in claim 1, A PI (Proportional-Integral) closed-loop controller is designed on a DSPIC microcontroller to regulate the speed of the induction motor and
3. Wherin the device as claimed in claim 1, , the PI controller parameters are tuned by the PSO algorithm.