Variable Speed Pump Performance Characteristics for Domestic Application

Aisyah Jilani,Akhtar Razali,S.A Abdul Karim,N Sa'Ad,N Zainuddin,M.H Yusof

doi:10.1051/matecconf/201822502005

Abstract

Generally, water pumps work at a fixed speed. Structural resonance in fixed speed can cause vibration. The reason that most single speed pumps utilize an excessive amount of electricity is that they are overused and oversized. Therefore, this research is embarked to study the characteristic of a pressure-controlled variable speed pump, develop the variable speed pressure controlled pump and analyse the pump performance. A technique is proposed to change the constant speed pump to variable speed pump by adding Variable Frequency Drive (VFD) and microcontroller. A simple test rig is designed and fabricated represented of water distribution for domestic use. The method was then experimentally validated to verify the pump performance and energy used. Data for water flow rate, water pressure, power output and pump speed were analysed. Since the speed can be lowered until 29.27% which according to the water volume demands, therefore the power consumption was found decreased and the lowest power is 0.014 kW. Maximum water discharge capability is 32.38 lpm. It is found that, a variable speed water pump able to save energy up to 97% and led to electricity bill saving and increase the life span of pipes and joints through less hydraulic pressure built-up.

Highlights

Fluid handling systems, for example fan and pump systems are culpable for a significant factor of total electrical energy use [1]
Energy consumption changed according to affinity laws which the torque is proportional to the square of speed, and power is proportional to the cube of speed
Variable speed pump system can be achieved by adding Variable Frequency Drive (VFD) which can be used for controlling the speed of Electrical Generator or Electrical Machines [6]

Summary

Introduction

For example fan and pump systems are culpable for a significant factor of total electrical energy use [1]. Energy consumption changed according to affinity laws which the torque is proportional to the square of speed, and power is proportional to the cube of speed. This variation helps to cut down the high energy losses compared to fixed-speed controllers or throttling devices for a relatively little reduction in speed [4]. Variable speed pump system can be achieved by adding Variable Frequency Drive (VFD) which can be used for controlling the speed of Electrical Generator or Electrical Machines [6]. R.Patel designed a VFD for industrial pump used that reduced 25% of power consumption with 10% reduction of operating speed and saves the energy cost [9]

Equipments and method

Results and discussion

Conclusion