Magnetic Bearing Technology:

Achievements in Higher Efficiency

Magnetic Bearing Compressor

• 100% Oil Free eliminates oil system

maintenance costs.

• R134a Refrigerant meets Montreal • R134a Refrigerant meets Montreal

protocol and is not subject to phase-

out.

• Magnetic Bearings eliminate frictional • Magnetic Bearings eliminate frictional

losses.

• One moving part assures long service • One moving part assures long service

life.

• Unmatched Efficiency as low as .30

kw/ton IPLV.kw/ton IPLV.

• Low 2-amp In-Rush Current reduces

installed cost and peak load.

• Lowest Noise - Only 70 dBa.

The Turbocor CompressorSoft-Start

Inverter speed 2 stage centrifugal

compressor

Soft-Start (

VFD and Inlet Guide Vane Operation

• The Compressors speed adjusts

automatically to match the load and automatically to match the load and

current operating conditions so that

optimum efficiency is gained.

• Primary capacity control is done using • Primary capacity control is done using

the onboard VFD and only use the Inlet

Guide Vanes to supplement VFD Guide Vanes to supplement VFD

controls. IGVs prevent surge conditions

at low turndown. IGVs normally

operate at the 110% position.operate at the 110% position.

• The slower the compressors, the

greater the efficiency. As speeds is

reduced, energy consumption is reduced, energy consumption is

reduced by the cube of the speed

The Magnetic Direct-Drive System

Magnetic bearings and sensors keep the shaft properly centered and positioned at all times. The Magnetic bearings and sensors keep the shaft properly centered and positioned at all times. The

rotor shaft is held in position with ten separately controlled electro magnetic cushions which

continually changes in strength to keep the shaft centrally positioned.

The shafts position is monitored with 10 sensor coils whose signal is fed back to a digital controller.

Movements of less than .00002”are sensed and adjustments are made accordingly.

Shaft is monitored and positioned 1,000 / sec.Shaft is monitored and positioned 1,000 / sec.

The Magnetic Bearing System

• Permanently magnetized shaft does not require

electrical power. electrical power.

• 97% energy efficient

• Uses 0.5% of the energy required for conventional

bearings.bearings.

• Eliminate high mechanical friction losses

• Eliminate oil-related heat transfer losses

• Eliminate cost of oil management systems • Eliminate cost of oil management systems

(controls and hardware)

• Increase equipment life through elimination of

wear surfaceswear surfaces

Leveraging Affinity Laws

Energy Used is Proportional to the Cube of the Speed of the Motor

Two pumps at 50% speed use 25% of the power of one pump at 100% speedTwo pumps at 50% speed use 25% of the power of one pump at 100% speed

Energy

100% 100%Speed

100% 100%

40% 7%

Optimizing the System involves leveraging Affinity Laws and Real-Time Tracking and Tuning of

Components to shift Load to where total PLANT ENERGY across all related components is reduced.

This is not simple PID loop feedback, but Dynamic Optimized kW Input

8

This is not simple PID loop feedback, but Dynamic Optimized kW Input

Variable Speed Factors

• Power is proportional to the speed cubed

• To achieve power reduction, the speed of fans, pumps and

compressors should be reduced at lower loads. compressors should be reduced at lower loads.

• Emerging VFD plant controllers optimize the technology.

• Flooded designs with water in tubes can limit flow range due to • Flooded designs with water in tubes can limit flow range due to

velocity and laminar flow issues. DX can be better solution in some

applications, but with efficiency loss.applications, but with efficiency loss.

•Cooling tower selections optimized for lower temp and flow. Can

increase installed cost yet reduce operation costs. increase installed cost yet reduce operation costs.

Why Is a Magnetic Bearing Compressor so Compelling?

Compressor Sizes and Uses

90 tons .375 17 tons

Capacity IPLV Turndown90 tons .375 17 tons

125 tons .359 28 tons125 tons .359 28 tons

150 tons .336 35 tons150 tons .336 35 tons

190 tons .342 55 tons190 tons .342 55 tonsChilled Water Range – 28F to 60F – 134a limited

Condenser Water Range – 50F to 90FCondenser Water Range – 50F to 90F

Ambient Range – 10F to 108-110F

Rule of thumb – 12 degrees minimum between LCHWT and ECTRule of thumb – 12 degrees minimum between LCHWT and ECT

Compact Size - Easy to ServiceCompact Size - Easy to Service

125 HP motor is in the foreground.

150 HP permanent magnet motor 150 HP permanent magnet motor

behind.

Variable-speed, magnetic bearing Variable-speed, magnetic bearing

and cooling controls.

High Capacity – Smaller Size

Oil-Free Eliminates Piping Complexity

No need for elaborate piping

designs compared with oil designs compared with oil

management systems.

• No traps and risers

• Lower installed costs• Lower installed costs

• Eliminates leak sources

Enables centrifugal chiller

with remote condenser to be with remote condenser to be

placed at greater distance.

Lowest Cost of Service

• Annually check electronics

for tight connectionsfor tight connections

• No oil service or oil

disposal - EVER.disposal - EVER.

•Replace capacitors every •Replace capacitors every

ten years

Lowest Noise and Vibration Levels

• “Best in Class” low sound levels. No

moving mechanical part touches any part of moving mechanical part touches any part of

the housing or frame to transmit acoustic

energy.energy.

• Tested at 70 dBa at 1 meter with no sound

attenuation. Other compressors, by

comparison, are approximately 80 dBa and comparison, are approximately 80 dBa and

higher.

• Vibration is essentially non-existent.• Vibration is essentially non-existent.

• The chiller with 5 compressors operating

at full speed only produces 75 DB of sound

at 10 feet., about the sound level of your at 10 feet., about the sound level of your

television.

What Happens with a Power Outage?

• In the case of a power outage, the compressor is fully protected.

• Within 0.5 of a micro-second, the motor becomes a generator which then • Within 0.5 of a micro-second, the motor becomes a generator which then

feeds power to the various controls and bearing actuators during a

controlled coast-down. The onboard capacitors have adequate power to fully controlled coast-down. The onboard capacitors have adequate power to fully

support the bearing system during the switch. Capacitors are replaced every

ten years.

•After the compressor comes to a complete stop, the rotor de-levitates

normally onto touchdown bearings. Carbon or roller touchdown bearings are normally onto touchdown bearings. Carbon or roller touchdown bearings are

also used as a back up bearing system to act as a cradle for the rotor during

the off-mode.

• The system then determines if normal power is restored, if YES, the shaft

levitates. If there is a call for cooling, the rotor will then begin to rotate. The levitates. If there is a call for cooling, the rotor will then begin to rotate. The

entire cycle from loss of power to normal operation takes about 1-3 minutes.

Automatic Bearing Compensation

This compressor continued to operate

even though this hole saw slug was even though this hole saw slug was

embedded in the 1st stage impeller.

The compressor is not designed to pump

hole saw slugs, however when faced with

this problem, the auto-balance feature this problem, the auto-balance feature

was robust enough to handle the

challenge. The compressor continued to

challenge. The compressor continued to operate at 35,000 rpm with this imbalance.this imbalance.

Turbocor Monitoring Software

Turbocor Monitoring Software

The Dramatic Effects of OilThe Dramatic Effects of OilASHRAE 601-TRP - Oil contamination can be caused by several factors, including gasket failure, ASHRAE 601-TRP - Oil contamination can be caused by several factors, including gasket failure,

but the most common cause of oil migration in comfort chillers is the continued use of a chiller at

low loads during the beginning or end of the cooling season. How much does excess oil in the

evaporator degrade performance? Table 1 gives typical ranges.

Oil in Evaporator Performance Loss

1-2% 2-4% loss

evaporator degrade performance? Table 1 gives typical ranges.

Percent Oil

1-2% 2-4% loss3-4% 5-8% loss5-6% 9-11% loss5-6% 9-11% loss7-8% 13-15% loss

ASHRAE study reached the same conclusion: “Flow boiling results have been obtained for newer

enhanced boiling tubes with R-134a. This enhanced tube shows a decrease in heat transfer with the

addition of even a small amount of oil throughout various heat loadings. Even at 1 percent (by weight) addition of even a small amount of oil throughout various heat loadings. Even at 1 percent (by weight)

oil, the heat transfer coefficient is reduced by 25 percent from its no oil baseline. At higher oil content, a

30 percent reduction has been typically measured.”

Oil causes 50% of downtime and cost

The Dramatic Effects of OilThe Dramatic Effects of OilPercent Oil

ASHRAE study shows

average percentages of oil

Percent Oil

average percentages of oil

present in chillers

Percent OilEfficiency loss in heat

exchangers account for Percent Oilexchangers account for

substantial operation costs

The Dramatic Effects of Oil

In the ten chillers tested in

the ASHRAE study, the the ASHRAE study, the

average overcharge of oil in

the system was 12.88%, this

equated to an average

Eff

icie

ncy

loss

-%

equated to an average

energy loss of about 21%

Eff

icie

ncy

loss

E

ffic

ien

cy lo

ss

Percent of oilPercent of oil

The Big Deal About Oil - Before

kW/Ton at AHRI relief conditions.650

.600

kW/Ton at AHRI relief conditions

CS Screw.550

.500 CS Centrifugal

CS Screw

VFD Oil.450

.400

CS Centrifugal VFD OilCentrifugal

.350

.300 $$$ LoadProfile.300

.250

.20020% 30% 40% 50% 60% 70% 80% 90% 100%

Arctic Centrifugal

$$$ Profile

.20020% 30% 40% 50% 60% 70% 80% 90% 100%

The Big Deal About Oil - After

.650kW/Ton at AHRI relief conditions

CS Screw.600

.550CS Centrifugal

CS Screw

Curves Include.500

.450VFD Oil Centrifugal

Curves IncludeAvg. Effect of Oil

.400

.350$$$

$$$

$$$

.300

.250 Arctic Centrifugal

$$$$$$

LoadProfile

.250

.20020% 30% 40% 50% 60% 70% 80% 90% 100%

Arctic Centrifugal

High Cost of Chiller Maintenance

Procedure Daily Weekly Quarterly Yearly

Record operating conditions (log) X

Check oil levels X

Check refrigerant levels X

Check oil return system X

Check operation of motor starter X

Check sump heater and thermostat operation X

Inspect and adjust safety controls X

Leak check and repair leaks X

Lubricate motor XLubricate motor X

Check and tighten all electrical connections X

Megohm motor windings XMegohm motor windings X

Perform oil analysis on compressor lube oil X

Replace oil filter and oil return filter/dryers XReplace oil filter and oil return filter/dryers X

Replace or clean starter air filters X

High Cost of Oil - BearingsHigh Cost of Oil - Bearings

Stop Operation & provide backup chiller (rental)

Open the compressor and hermetic motor for inspectionOpen the compressor and hermetic motor for inspection

In addition to normal annual maintenance, inspection occurs every 40,000 hrs of In addition to normal annual maintenance, inspection occurs every 40,000 hrs of

operation or every 5 years, whichever occurs first. 5 times during a 30 year

service life. Screw chillers not optional!

Shutdown, disassemble motor,

replace bearings, replace seals.replace bearings, replace seals.

Cost approximately $25,000 each

time 5 times over 30 year service time 5 times over 30 year service

life $125,000 over life of equipment.

Burnout & oil induced acid eliminated.

Magnetic Bearing Chillers vs Screws

ARI 550/590-1998 Conditions

Leading ScrewWATER COOLED

Magnetic Bearing CompressorWATER COOLED

Load ECWF/C

LCHWF/C

SSTF/C

SCTF/C

COP kW/Ton SSTF/C

SCTF/C

COP kW/Ton

100% 85/29.5 44/6.7 42/5.6 98/36.7 5.33 0.64 42/5.6 98/36.7 5.56 0.63100% 85/29.5 44/6.7 42/5.6 98/36.7 5.33 0.64 42/5.6 98/36.7 5.56 0.63

75% 75/23.9 44/6.7 42.3/5.8 89.6/32 5. 73 0.6 42.3/5.8 85/29.5 7.31 0.48

50% 65/18.3 44/6.7 42.5/5.9 89.6/32 5.49 0.64 42.5/5.9 72.2/2.2 11.38 0.3050% 65/18.3 44/6.7 42.5/5.9 89.6/32 5.49 0.64 42.5/5.9 72.2/2.2 11.38 0.30

25% 65/18.3 44/6.7 42.8/6. 89.6/32 4.11 0.845 42.8/6 70/21.1 10.86 0.32

IPLV COP kW/Ton 5.4 .65 9.55 0.36

Conclusion – The magnetic bearing compressor is 45% more efficient

than the leading screw compressor

Magnetic Bearing Chillers vs Screws

ARI 550/590-1998 Conditions

Leading ScrewAIR COOLED

Magnetic Bearing CompressorAIR COOLED

Load AirF/C

LCHWF/C

SSTF/C

SCTF/C

COP kW/Ton SSTF/C

SCTF/C

COP kW/Ton

100% 95/35 44/6.7 35.5/2 122/50 3.19 1.10 35.5/2 122/50 3.08 1.13

75% 80/26.7 44/6.7 36.5/2.5 104/40 4.20 0. 83 36.5/2.5 104/40 4.44 0.79

50% 65/18.3 44/6.7 37.5/3 86/30 5.26 0.69 37.5/3 82.5/28 7.23 0. 48

25% 55/12.8 44/6.7 38/3.5 86/30 3.98 0.88 38/3.5 66.2/19 9.77 0.35

IPLV COP kW/Ton 4.6 0.76 6.32 0. 55

Conclusion – The magnetic bearing compressor is 29% more efficient

than the leading screw compressor

A/C Efficiencies Now Finally Approaching W/C

2.5

3.0

95°F Ambient temps

1.5

2.0Typical Air-Cooled

Screw Chiller

85°F

75°F

65°F

.80

.90

1.0

Arctic Cool

Chiller

at ambient temps

Air-Cooled

.60

.70

.80

85°F

80°F

75°F

TypicalScrew

Water-Cooled

95°F 85°F75°F

at ambient temps

.40

.50

.60 75°F70°F

65°F

60°F

ChillerWater-Cooled

condenser temps

65°F

For fans at Gillette Stadium, Boston

Percent of Load

20% 30% 40% 50% 60% 70% 80% 90% 100%.30

For fans at Gillette Stadium, Boston

One of five 400 ton chillers

Standard Stacked Design

• Oil-Free design eliminates frictional

losses and high cost. losses and high cost.

• Lowest IPLV in the industry.

• Variable-speed Drive.• Variable-speed Drive.

• Flooded evaporator/condenser for

thermal buffer and close approach.thermal buffer and close approach.

• Cleanable condensers/evaporators.

• NEMA 1 Panels Standard.• NEMA 1 Panels Standard.

• Danfoss Controls Standard

• Marine Water Boxes Optional.• Marine Water Boxes Optional.

Optional Low Profile Design

Standard designs include

stacked, offset and low stacked, offset and low

profile.

Optional Economizers Optional Economizers

boost capacity and

efficiency

Split systems are Split systems are

available.

Multiple Circuits Multiple Circuits

available.

Condenser-less and Condenser-less and

Condensing Units

available.

Water Cooled Chillers

• Up to eight compressors • Up to eight compressors

per chiller

• Provides the ability to use • Provides the ability to use

the entire heat transfer

surface even when using

few compressors, thereby few compressors, thereby

ensuring close approach

temperatures.temperatures.

•Water cooled products

from 50 to 1,500 tons.

Highest Efficiency and ReliabilityHighest Efficiency and Reliability

Combined Duty System – Off the GridCombined Duty System – Off the Grid

�

HOT WATER SUPPLY

� CHILLED WATER SUPPLYCHILLED WATER RETURN

TURBINE INLETAIR COOLER EXHAUST

CONTROL

ABSORPTIONCHILLER

Base-Loadedfor kW Balance

CONTROLVALVE

POWERGENERATOR

TURBINE

for kW Balance

MAGNETIC PART-LOAD CHILLERGENERATOR

Energy efficient benefits include sizing and balancing the

absorption chiller to the base load to assure steady-state absorption chiller to the base load to assure steady-state

output, and using the variable-speed magnetic chiller to meet

varying load demands above and below base load, and to

provide system redundancy for the absorption and power provide system redundancy for the absorption and power

system.

Air Cooled Chillers

• Dedicated Circuit per • Dedicated Circuit per

compressor up to 400

tons or 4 circuits.

• Assures that

refrigerant is properly

managed during staging managed during staging

and load variations.

•Eliminates the known •Eliminates the known

issues of refrigerant

migration with single

circuited centrifugal circuited centrifugal

compressors.

Modular Chillers

• Modules with Scroll, Screw or

Turbocor Compressors. Any size.Turbocor Compressors. Any size.

• Air cooled, water cooled, free-

cooling and VFD pumping systems cooling and VFD pumping systems

are available.

Heat Recovery Chillers

APPLICATIONS

• Sites with constant chilled and hot water demand.• Sites with constant chilled and hot water demand.• Hospitals, Hotels, Nursing Homes, Universities• Process Heating and Cooling Loads

HEAT RECOVERY USES

• Building Heating Loops• Domestic Hot Water• Domestic Hot Water• Process Hot Water• VAV Reheat• VAV Reheat• Swimming Pool Heating• Laundry Facilities

Lowest Total Cost of OwnershipLowest Total Cost of Ownership

• Lowest Energy Consumption – low as .30 IPLV• Lowest Energy Consumption – low as .30 IPLV

• Don’t rely on just NPLV but do full energy analysis

• Lowest Noise Levels – 70 dB compressor• Lowest Noise Levels – 70 dB compressor

• NO Oil Maintenance Costs

• NO Degradation of Tubing U-Value, Min 8%• NO Degradation of Tubing U-Value, Min 8%

• NO Compressor Rebuild Cycles - High MTBF

• Advanced Genuine Danfoss Controls• Advanced Genuine Danfoss Controls

• Qualifies for Deepest Rebates, LEED Points.

• Fuel Cell Project – DC to DC lowest cost

•Reverse flow generator powers compressors.

Why Chose Magnetic Bearing?

ASHRAE Expo Canadian ASHRAE Expo

Energy Innovation

Award

Canadian

Energy Award

Award

Frost & Sullivan