550 likes | 766 Views
HVAC & WATER Application note. Imola – June, 19 2013 - 01. HVAC & WATER. HVAC Heating , Ventilation and Air- Conditioning (HVAC) is all about efficiency : Room temperatures need to be maintained at optimum levels to achieve the best occupant confort.
E N D
HVAC & WATER Application note Imola – June, 19 2013 - 01
HVAC & WATER • HVAC • Heating, Ventilation and Air-Conditioning (HVAC) isallaboutefficiency: • Room temperaturesneed to be maintainedat optimum levels to achieve the best occupant confort. • Itisessential to considerhow hit targets in reducingcosts and carbon dioxide (CO2) levels.
HVAC & WATER • WATER - PUMP • An operatingpumpwillnormallyconsume more powerthan the hydrauliccircuitrequires and itisusuallypositioned in unconfortable site: • Itisessential to considerhowachieve targets in reducingpowerconsumption, costs and CO2levels. • Maintenance time and costsneed to be reduced in order to avoid long plantstandstill.
HVAC & WATER - Why VFD flow control? HVAC & WATER systems are designed to operate under the most extreme conditions and, HVAC typically, in the“worst case” situations that the system will encounter Most of the time they have excess capacity
HVAC & WATER - Why VFD flow control? • Problems of traditional flow control • Lowsystemefficiency • Difficult in regulation • Electromechanical stress • Noise due to mechanicalresonance • High startingcurrent • Big supplycablesection or cablenumber • Maintenancecost and time
HVAC & WATER - Why VFD flow control? Reducing the capacity of the systems when full capacity is not required provides significant energy savings without sacrificing system performance VFD Flow control
Secondary Hot/ChilledWater Pumps Cooling Tower Fans Supply Fan Condensor Water Pump Primary cold/Chilled Water Pumps Return Fan HVAC & WATER
Pump Curve OperatingPoint System Curve HVAC & WATER - Characteristic
Pressure drop HVAC & WATER - Traditional throttling flow control New Power required WASTED Power P Power Flow x Pressure Power to load
Secondary Chill Water Pump Differential Pressure Air Air Air Air Sensor Chiller Duct Duct Duct Duct Cooling Cooling Cooling Cooling Coil Coil Coil Coil Primary Chilled Water Pump Secondary Chilled Water Pump Drive HVAC & WATER - VFD flow control VFD avoids the pressure drop by controlling the speed of the pump
P HVAC & WATER - VFD flow control «Throttle control» Power required «VFD c.» Power required
HVAC & WATER - VFD flow control Proportional Integral Derivative function (PID) The sum of these three actions is used to adjust the process via a control element such as the position of a control valve or the power supply of a heating element. PID controllers attempts to correct the error between a measured process variable and a desired set-point by calculation and then outputting a corrective action that can adjust the process accordingly.
HVAC & WATER - VFD flow control The target value or Set-point has to be set by user. This could be the desired pressure, flow, temperature, vacuum, etc. E.g.: this reference is the measure of how much fluid is required to be sent to the wastewater pipeline. VSD Motor & Pump Set point Controller Pump outlet Motorfreq. Actuating Signal Controlled Variable Set point System Σ Comparator 0-10VDC or 4-20mA signal Detector Feedback value Feedback value Transducer
HVAC & WATER - VFD flow control • The standard «ready-to-install» IP54 SINUS PENTA solutionisparticularlysuited to HVAC & WATER applications: • High degree of protectionagainstdust and water sprays • Ability to mount without additional enclosures and ventilation • PID functions for automatic control • Built-in EMC filter • Onboard communications allows control and monitoring
HVAC & WATER - VFD flow control • The standard «ready-to-install» IP54 SINUS PENTA solutionisparticularlysuited to HVAC & WATER applications: • Extensive I/O with internal comparator functions • Fire Mode function for extended operation in critical periods • Speed Search function to start on a rotating load • Real Time Clock (RTC) function to adjust confort to demands that change over the week • Multipump function • Robustness and reliability
HVAC - SINUS PENTA advantages • AIR HANDLER • Reduce energycosts and CO2emissionsVariable torque loadcharacteristics use lessenergyasspeedisreduced • Reduce supplydemandDrives reduce motorstartingcurrent up to 10 times • Reduce noise in buildingsAirflownoisedecreases by eliminatingstarts/stops and optimising flow rates • Reduce shock and vibrationDrive avoidsrunningatspeednearsystemresonantfrequency and providescontrolledacceleration • Increased life of motorbeltsDrivesprovidelow torque startsreducing stress on belts, pulleys and keys
HVAC - SINUS PENTA advantages • WATER CONDENSER CHILLER • Reduce energyconsumptionProvideimprovedefficiency and reduce energyrequirements • Reduce CO2emissionsDue to the energysavings • ProvidecontinuousoperationRestart a spinning motoraftermomentarypowerloss
HVAC - SINUS PENTA advantages • COOLING TOWER FAN • Energy savings and reduce energycostsMotor use lessenergyasspeedisreduced • Reduce CO2emissionsDue to the reduce energyconsumption • Reduce maintenancerequirements and reduce operatingcostsRobustconstructions and energyefficient
WATER - SINUS PENTA advantages • PUMP • Reduce energycosts and CO2emissionsVariable torque loadcharacteristics use lessenergyasspeedisreduced • Reduce demandchargesDrives reduce motorstartingcurrent up to 10 times • Control of pressure of flow using PIDThe drive can optimize the pressure flow, and itslinearityvariations, with a single pressure transducer • Wide powerrange for differentpumpsizes • Network communicationsSupportall major protocols • Prevention of water hammer, pipe stress, valve, pumpseals and cavitationExtends the life of the entiresystem
WATER - MULTIPUMP application overview Controls a multi-pumppumpingsystem (up to 5 pumps) Onepumpis the speed-controlled master and the otherpumps are variablespeed or fixedspeedslaves Multi-Master mode Connection using I/O or Modbus Automaticbalancing of operating hours of allpump sets Elimination of water hammer
WATER - MULTIPUMP: Fixed Speed Slaves (FSS) The Master pump operates to ensure the system fine-tuning. The slave pumps are started up/stopped based on the criteria below: • Percentage of the working power required for the master pump (allowing optimum performance of the plant). • Maximum allowable adjusting error. • Maximum difference among the working time of each available pump. The power ratio of the connected pumps must meet one of the following requirements: • All pumps must have the same power ratings. • The connected pumps can have different power ratings, provided that each pump with the greatest power rating is matched with lower-rated pumps that, if combined, have power ratings equal to or higher than the former pump. • The power rating of the master pump must be higher than/equal to the power rating of the lower-rated pump.
Soft-Starter ASAB Soft-Starter ASAB Soft-Starter ASAB Soft-Starter ASAB WATER - MULTIPUMP: Fixed Speed Slaves (FSS) PENTA MULTIPUMP SOFTWARE Basic diagram for a fixed-speed plant including 4 slave devices and 1 MP Penta drive controlling the system in analog mode.
WATER - MULTIPUMP: Variable Speed Slaves (VSS) The slave pumps and the master pump are started/stopped based on the following criteria: • Percentage of the working power required for the master pump (allowing optimum performance of the plant). • Maximum allowable adjusting error. • Maximum difference among the working time of each available pump. All the connected pumps must have the same power ratings.
MULTIMASTER FUNCTION PENTA MULTIPUMP SOFTWARE PENTA DRIVE PENTA DRIVE Modbus MASTER Modbus SLAVE MODBUS RTU WATER - MULTIPUMP: Variable Speed Slaves (VSS) PENTA DRIVE The diagram above shows a configuration for a variable-speed multipump system, serial communications and Multimaster function.
Outside Air Damper Supply Fan Cooling Heating Coil Coil Pressure Sensor Return Air Damper Return Fan Relief Air Damper Supply Fan Drive HVAC & WATER: Variable Air Volume (VAV) Supply Fan Conditioned Space
HVAC & WATER: Supply Fan - Temperature Conditioned Space T T Supply Fan Supply Fan Drive
Outside Supply Air Damper Fan Conditioned Space Reverse this fan Close this dampe r Return Air Damper Smoke Sensor Return Fan Relief Air Damper Supply Fan Drive HVAC & WATER: Supply Fan - Smoke Extraction
HVAC & WATER: Stairwell Pressurization Fan Tp Fire mode function Fan Drive
CO Vent. Sensor Fan Vent. Fan Drive HVAC & WATER: Parking Garage Ventilation Fan Smoke Sensor
HVAC & WATER: Fume Hood Fan Fan Fume Hood Fan Drive
HVAC & WATER: Cooling Tower Fan Cooling Tower Cells Chiller Temperature Condenser Sensor Water Pump Cooling Tower Fan Drive
HVAC & WATER: Condenser Water Pump Flow Sensor Chiller Cooling Tower Strainer Condenser Water Pump Drive