Voltage Stabilisation & OptimisationTHE FACTS 

OVERVIEW

• Who are we?

• What is Voltage Power Optimisation?

• What equipment does it work on and how well?

• Historic results

• Voltage Balance

• Types of VO

• Questions…

• 20 years as a power supply engineer and senior manager in NSW

electricity industry (now called Ausgrid)

• 20 years in the energy efficiency industry developing many large

energy saving projects in NSW, Qld, Vic and WA

• More than 10 years on the board of the Australasian Energy

Performance Contractors Association (now Energy Efficiency

Council)

• Implemented many successful energy saving Voltage Optimisation

solutions for Supermarkets, Office buildings and Hotels.

Presented by: DEANE GUDSELL

• Specialist Power Quality and Energy Saving solutions provider and manufacturer.

• Proudly Australian owned and a member of the Ampcontrol Group of companies. Ampcontrol have been providing electrical engineering services since 1968 in Australia, New Zealand and overseas.

• Market leader in Power Factor Correction manufacture and supply for over 30 years

• Introduced the European manufactured Ortea VPO to the range in 2013. Ortea have been supplying VPO and stabilisers world wide for decades.

CAPTECH

CAPTECH REFERENCES

CapTech equipment can be found in all facets of industries such as in supermarkets, Schools & Universities, 

Government & Office Buildings, Power Authorities, National and International Manufacturers.

WHY SHOULD YOU BE INTERESTED?

VOLTAGE OPTIMISATION DELIVERS:

• REDUCED electrical energy (kWh) COSTS

• REDUCED maximum demand/penalty (KVA & KW) COSTS

• STABILISE and BALANCES supply voltage (some do)

• PROTECT plant life expectancy

• PROTECT your processes/production (some do)

1. Supply voltage is 240V (415V) and is steady

2. The voltage on each phase of my supply is always balanced

3. Motors are all designed for 240V (415V) supply voltage

4. Reducing voltage below 240V will burn out my electric motor

5. Power Factor Correction is the same as Voltage Optimisation

6. All electrical equipment will use less energy with reduced voltage

7. All VPO’s deliver the same results

All of the above are wrong or at least mostly wrong

MISCONCEPTIONS

• VO – Voltage Optimisation

• A reduction and balancing in electricity supply voltage that achieves a saving in energy consumption (kWh) and a reduction in maximum demand (KW & KVA).

• Achieved by better matching supply voltage with the design voltage for your electric motors.

VO DEFINITION

• Supply voltage varies over time and with location

• 245 - 247V is the most commonly recorded average supply voltage

• Electricity Supply Voltage standard (AS/NZ60038-2000)

o 230V +10%/-6% (253V-216V phase to neutral)

o 400V +10%/-6% (376-440V phase to phase)

WHY? - SUPPLY VOLTAGE

Neutral

230V

400V

L1 L2

L3

1. Optimisation/reduction of supply voltage will normally reduce energy

consumption of inductive electrical equipment like motors and some

older type lighting

2. Energy consumption reduction varies dependent on

– the average reduction in voltage achieved

– the stability of the reduced voltage

– the phase voltage balance

– type of electrical equipment connected.

3. Motor nameplate voltage rating is most often 220V (380V 3-phase)

VO FACTS

• HVAC systems and Refrigeration are the sweet spot for VO

• Saving varies based on motor design voltage & mechanical

load

• VFD’s reduce the level of saving for motors from VO

• Inverter HVAC – no saving from VO

• Electronic Power supplies like LED lighting and IT equipment

like Gaming Machines – no saving

RULE OF THUMB

OPTI netENERGY SAVING ST@BILISER

VOLTAGE STABILITY

SUPERMARKET – 12.3% WHOLE SITE

12.3% energy saving year to year raw data ‐ Dungog IGA

SUPERMARKET – 13% WHOLE SITE

13% whole site energy saving regression analysis, taking weather variables into accountDungog IGA

M&V using IMPVP

SUPERMARKET – 14.4% WHOLE SITE

14.4% whole site kWh energy saving and 12.2% reduction in Maximum Demand

AQUATIC CENTRE

Results: energy consumption saving – Aquatic centre 17% saving Regression analysis kWh taking into account temperature and relative humidity pre and post installation

M&V using IMPVP

COMMERCIAL OFFICE – 11% SAVING

Results: energy consumption saving – Office Building 11% saving

Before

After

ENERGY SAVINGS OPPORTUNITY

Good energy savings

ENERGY SAVING OPPORTUNITY

Good energy savings

ENERGY SAVING OPPORTUNITY

No saving ….. But no harm by lowering voltage

• Name-plate rating for 3 phase motors is commonly 380V (220V) for 50Hz.

• Sometimes is 400V, 415V, & rarely higher

• NEMA stipulate that a motor should operate normally for

• voltage range +/-10% of the nameplate voltage

• Limit of voltage unbalance should be 1%

MOTORS

• Very rare name-plate 430V …..but they do exist

• 430 VL-L = 248 VL-N

• Not for Voltage Optimisation

MOTORS – know when to fold em!

EFFECT OF VOLTAGEVARIATION ON MOTORS

Reference – Electric Motors & Voltage – The Cowern Papers

Design voltage

EFFECT OF VOLTAGEVARIATION ON MOTORS

Refrigeration Compressor Motor

Supply voltage

Design voltage 220V

• Out of balance voltages can cause significant energy loss (heat) in three phase motors.

• Balanced voltage on each phase separately can save even more energy & improve asset life

VOLTAGE PHASE BALANCE

Supply Voltage

VO StabiliserOutput

2% Unbalanced voltage

• NEMA states that three motors shall operate successfully at rated load when unbalance voltage does not exceed 1%

• Unbalanced voltages cause phase current unbalance from 6‐10 times the percentage voltage unbalance for a fully loaded motor. 

• Unbalanced voltage of 2.3% can cause up to 300C temperature rise in the motor.

VOLTAGE UNBALANCE

CharacteristicAverage Voltage 230 230 230Unbalanced Voltage 0.3% 2.3% 5.4%Unbalanced Current 0.4% 17.7% 40%Increased Temerature Rise 0 30 C 40 C

Performance

Reference – Unbalanced Voltages and Electric Motors: Causes and Consequences, elongo.com

• Winding insulation life is approximately halved for every 100C increase in winding temperature.

• Motor losses increase 25% with a 4% unbalance voltage 

Reference – Unbalanced Voltages and Electric Motors: Causes and Consequences, elongo.com

VOLTAGE UNBALANCE

SAVINGS VARY BY EQUIPMENT TYPE

0%

5%

10%

15%

20%

25%

Inverter &VRV HVAC

T5 & LEDelectronicballastlighting

Laptop &Desktop PC& Flat screen

VSD drivenmotors

Pool Pump Fan motor HVACpackaged

Refrigerator(domestic)

Commercialrefrigeration

CFL lighting Halogenlighting

T8 MagneticBallastlighting

HID lighting(magneticballast)

Energy Savingexpected from a 10% voltage reduction

low

high

SAVING CALCULATION

Voltage reduction and type and mix of electrical equipment is critical to estimating the potential energy and demand savings

Load type% of total 

loadkWh 

usage/year

Benchmark ‐ Saving per 10% volt reduction

Saving per actual volt reduction

Energy Savings predicted kWh/yr

Refrigeration no VSD 10% 195,412           15% 15.7% 30,660         Refrigeration ‐ with VSD 0% ‐                    4% 4.2% ‐               Lighting ‐ Mag Ballast 0% ‐                    18% 18.8% ‐               Lighting ‐ Electronic Ballast 10% 195,412           0% 0.0% ‐               IT and office equipment 10% 195,412           0% 0.0% ‐               Cooking (electric) other 5% 97,706             0% 0.0% ‐               Pumps fans and general motor 0% ‐                    12% 12.6% ‐               HVAC ‐ no inverters or VSD's 55% 1,074,767        12% 12.6% 134,904       HVAC ‐ with VSD's 10% 195,412           4% 4.2% 8,176           Total 100% 1,954,122       8.9% 173,739      

ENTER Total annual kWh 1,954,122  Voltage reduction possible 10.46%Target output voltage 220.0          Average Voltage 245.7          

CONNECTING VO & PFC

PFCL

Transformer

Main Switchboard

Circuit Breaker

11kV

LV

CT

IT

LV

220VVO

247V ?

VO

Mechanical Services

TYPES OF VO

Type of VO Outcomes

Step‐down VO • Least energy saved• Output fluctuates with input volt changes• None or minimal phase voltage balancing

Automatic VO • Slow adjustments • More accurate output than Step‐down VO but not 

a stable output voltage• Minimal phase voltage balancing• More energy saved than step down VO

Automatic VO Stabiliser

• Fast adjustments <20mS• Highly accurate and stable output voltage <0.5%• Accurate phase voltage balancing <1.0%• Most energy saved

1. Build Quality2. Proven reliability in hot and humid environments

3. Track record4. Stability of output voltage based on speed of operation, input range

and accuracy (Fastest and most accurate output the better)5. Independent phase voltage control (balance)

6. Technical support - Depth, capability and geographic coverage of supplier in Australia

7. Business strength and longevity of both manufacturer andsupplier in Australia.

VO SUPPLIERSELECTION CRITERIA

VOLTAGE OPTIMISERSOptinet series by CapTech

• Fast 18 millisecond automatic response time• Independent phase voltage control• Highly accurate output voltage +/- 0.5%• Surge Protection • Bypass switch• Input/output display• Voltage output can be set from 210-255V L-N

• Optional +/-30% voltage range for stable output (Supply input 161V-300V)

• Warranty 15 years on magnetics, 3years on other• Tens of thousands of units installed worldwide (Europe, UK, Africa, SE Asia, Middle East

and Australia)

OPTI netENERGY SAVING ST@BILISER

Supply Output

253V‐220V L‐NStable

220V +/‐0.5%

Voltage Optimiser& Stabiliser referencesSome Ortea VO Australian and International reference sites:

• Save Electrical Energy

• Reduce Electricity Demand/Penalties

• Protect expensive equipment

• Doesn’t work for everything

• Different results by equipment type

• Saving can be predicted.

VOLTAGE OPTIMISATION& STABILISATION

For more informationDeane Gudsell – deane.gudsell@captech.com.au ph: 0412 687848