-SAMARTH PAWARDR. TADUESZ CZASZEJKO

DIRECT ELECTRIC HEATING OF DOMESTIC WATER

INTRODUCTIONAIM

Heat Water by passing electric current directly through it.

Limit CurrentPrevent Electrolysis of Water

INTRODUCTION

POWER SUPPLY UNITAC source / Rectified DC

sourceCONTROLLER UNIT

HEATThermocouple

CURRENTHall Effect sensor

ELECTRODESParallel plateR=ρ*length/surface area

POWER SUPPLY

CONTROLLER

COLD

HOT

POWER SUPPLY

Low Peak to RMS ratio.Firing Angle control of thyristor.H-Bridge switching , emulating alternating

current.Low losses.

CONTROLLER SOLUTIONCONTROL PARAMETERS

Reference Current(Ir)Reference Temperature(Tr)

WATER MODEL PARAMETERSLength, Width (gap between electrodes), Height,

Resistance, Flow Rate and Initial Temperature.

Tr PI(t) PI(i)PLANT1: POWER SUPPLY

PLANT2: ELECTRODES

-1

-1

Et Ir Ei α I T

PSIM SIMULATIONS – (flow rate)

FLOW RATE = 9L/m, R=5 Ohms, Initial Temperature = 0 FLOW RATE = 7.8L/m, R=5 Ohms, Initial Temperature = 0

FLOW RATE = 6.6L/m, R=5 Ohms, Initial Temperature = 0 FLOW RATE = 0.5L/m, R=5 Ohms, Initial Temperature = 0

PSIM SIMULATIONSFLOW RATE = 9L/m, R=4 Ohms, Initial Temperature = 0 FLOW RATE = 9L/m, R=1 Ohms, Initial Temperature = 0

FLOW RATE = 9L/m, R=5 Ohms, Initial Temperature = 10 FLOW RATE = 9L/m, R=5 Ohms, Initial Temperature = 20

EXPERIMENTAL SET UP

Isolation Step Down TransformerDiode BridgeCapacitor-470uFResistor-112 Ohms Load bank setting.Dead time control

MINIMUM DEAD TIME OF 4US CLOSER TO MAXIMUM DEAD TIME

MINIMUM DEAD TIME , SHOWS RECTIFIED VOLTAGE SWITCHING VOLTAGES ACROSS THE ELECTRODES

CONCLUSIONSUniversal water heater – higher supply

voltages, support wide range of resistivity’s.

CONCLUSIONSUse of Simulation Model

Better ElectrodesDifferent components

Alternate MethodsBuck/Boost Convertor topologiesDevelopment of better inductors

Experimental Set Up can be used with electrodes with isolation.

ACKNOWLEDGMENTDr. Tadeusz CzaszejkoMr. Ian Reynolds, Mr Ray Chapman and Mr

Ray CooperSpecial thanks to David PetzerThank You Supervisors