Dynamic Modelling of Submersible Pump Based Solar Water-Pumping System with Three-Phase Induction Motor Using MATLAB

Faisal Alkarrami, Tariq Iqbal, Kevin Pope, Geoff Rideout
2020 Journal of Power and Energy Engineering  
The main purpose of this paper is to design and model a water-pumping system using a submersible multi-stage centrifugal pump driven by a three-phase induction motor. The system is intended for pumping water to the surface from a deep well using three power supply systems: a general network, a photo-voltaic (PV) system, and a PV system with a battery bank. These systems are used to compare two three-phase induction motors-namely, a motor with a drive and another one without a drive. The systems
more » ... drive. The systems dynamic models are simulated in MATLAB/Simulink and the results compared with the manufacturer's data for validation purposes. The simulation results generally show system dynamics and expected performance over a range of operation. other pumps that can be used include diaphragm pumps and progressing cavity pumps. In general, these pumps have relatively high efficiency, along with minimal capital costs and PV input power needs [3] . Positive displacement pumps are designed to provide a fixed amount of water through the contraction and expansion of a diaphragm. Both centrifugal and positive placement pumps are used for the same purpose, which is to reduce downtime from main events and to continuously move water from point A to point B [1] [2] . In the present work, we investigate a dynamic pump, which is a type of centrifugal pump. We chose the dynamic pump mainly because of its low maintenance needs. However, centrifugal pumps can be problematic in that their efficiency reduces under low levels of solar radiation. To offset the problem, we modify motor speeds depending on the irradiance that is available at any given time. Note that the pump's torque is generally proportional to the rotor speed's square [4] [5] . Especially in rural areas and places that are underserved by national or regional grids, photovoltaic water pumping systems (PVPSs) have been shown to have great promise for providing solar energy [6] [7]. PVPSs are not only cost-effective but also dependable in comparison to grid-or diesel-based pumps [8] . Currently, the most common forms of water pumps being used in rural areas are diesel generators (DGs), but PVPSs offer a more dependable, less noisy and cleaner option [2] [9]. Diesel and electric water pumps spew 45 million tons of CO2 into the environment every year. This is equal to around one-tenth of all the world's annual emissions of greenhouse gases (GHGs). In an attempt to deal with these problems sustainably, the government in India initiated a program using solar-powered pumps to supply water for drinking and agricultural purposes. Solar water pumping has been found to be a viable alternative in water supply systems, particularly in light of rising diesel fuel prices [2] . After installing 0.1 million Solar Photovoltaic Water Pumps (SPVWPs) by 2015, the government now aims to add 1 million more by 2021 [10] [11] . Water pumping systems operated by direct coupled DC and AC solar-run water pumps are being used in many places around the world. The key parameters to determine the viability of these systems are as follows: adequate amounts of solar radiation based on geographical location; daily water needs during maximum usage periods; static level measurements; and piping requirements, as determined by pressure drops, height of tanks, and maximum drawdown [12] . In general, standard solar water pump systems include a motor pump set, a water storage tank, a controller, a photovoltaic (PV) array, some form of mounting structure, a tracking system (automatic or manual), and protection devices. PV modules can be linked in parallel and in series to operate pump-motor sub-systems. These systems need power in order to generate the required water flow and pressure [3] . PV arrays connect with DC links via a DC/DC boost converter as a means to enable maximum power point tracking (MPPT) control, while three-phase voltage source inverters are used to maintain DC-link voltages [5] [7] [13] [14]. F. Alkarrami et al.
doi:10.4236/jpee.2020.82002 fatcat:qw5ikfogj5fslp6ju23sggifzy