June, 2013 Brief Introduction AC Drive to control motor speed General Electric Power - To control AC motor speed and torque by varying motor input frequency from a certain level of frequency (60/50Hz) - To vary frequency, AC drive converts AC power to DC, inverts DC to AC and controls motor speed by supplying power to a motor AC / 60Hz AC / Command Hz General-Purpose Motor 2.AC Drive Structure 1. AC Drive (or Inverter / Variable Frequency Drive) 4 / 10 Converter Smoothing Circuit Control Circuit ConvertingAC to DC Inverting DC to AC with varied frequency Smoothing DC Inverter AC Drive1/22 Brief IntroductionMotor Speed (N, rpm) =120 x Frequency (f) Number of Pole (Motor)(P) Generally, a motor constantly runs at 1,800rpm with general electric power (60Hz) supplied from a power company. Using AC drive which controls power frequency, users can operate a motor at variable speed. For example, if a drive sets frequency at 1Hz, a motor runs at 30rpm.(If 2Hz and 30Hz, 60rpm and 900rpm, respectively) = 30 x Frequency (f) Remark) 1. The number of general motors pole is 4 2. Slip isnt considered 3. Principle of Controlling Speed 2/22 Advantages of Using AC Drive Advantages of Using AC Drive Even if power supply isunstable, it controls motorat constant speed. It leads energy saving by consumingonly sufficientamount of electricity to controlmotor speed as required. Easy to use and control The growth of productivityas applied to factory automation By using AC drive, Users can control standard 3-phase motors at their command. Product Quality Improvement Energy Saving Productivity Increase Protecting Outside Environment Easy to Use During operation, it minimizes effects to outside by increasing electric power stage by stage.(While starting high capacity motors directly, outside power supply or devices would be damaged.3/22 Energy Saving Effect Theoretically, if it runs at maximum frequency 55Hz, 23% of total energy consumption can be saved. (if 50Hz, 42%). The result of actual operation describes that it runs at 55Hz and 50Hz, 20% and 37% energy would be saved due to drive efficiency and other effects. (Source: Korea Electro technology Research Institute) Energy Saving Effect DAMPER control AC Drive control Energy Saving 0 Y1 Y2 Y3 Pressure Flow (Air Volume)X1X2 (100%) 4/22 VSDs `could save more than 56bn` in ten nations Wider use of variable speed drives (VSDs) by industry could save ten of the worlds leading economies a combined total of more than 56bn over the next five years, according to a new analysis by Siemens Financial Services (SFS). The study shows that the savings in the US could exceed 16.7bn, in China 8.6bn, Russia 7.2bn, Germany 6.4bn, India 5.4bn and the UK 3.1bn. The other countries included in the survey (and shown in the graph above) are Spain, France, Turkey and Poland. SFS claims that its figures are cautious and conservative, being based on average VSD energy savings of 25% and electricity prices and consumption data from 2010, for example. Although it is estimated that 5070% of industrial processes could benefit from using motors controlled by VSDs which typically cut energy consumption 2070% the current penetration rate of VSDs as a proportion of installed motors is just 1020%.The potential savings are substantial because more than 95% of the lifetime costs of running an industrial motor come from the cost of the electricity it consumes.Source : World news: November 2012 Drive & Controls Energy Saving Effect 5/22 E/L Door Performance / Function High (Vertical Load) Medium (Normal Load) Low (Simple Load) Capacity ~ 3.7kW5.5 ~ 22kW30 ~ 450 kW450kW~ Simple Conveyor Packaging (Food etc) Socks-Knitting Machine Flat-Knitting Machine Circular-Knitting Machine Spin-Dryer Industrial Washing Machine Centrifuge Conveyor / Carrier Bogie Wood Milling Machine Applications Machine Tool Parking Equipment (Tower) E/L (High Speed) Printing Press Metalworking Machine Hoist (Winding) Parking Equipment (Puzzle) Ejector Stir / Extruding Machine Crane (Winding) Process Control Line (Paper Manufacturing, Steel etc) Fan / Pump / Blower Compressor Vehicle Manufacturing Line Crane & HoistWater Treatment Steel & PaperBuilding Packaging & Conveyor Energy Saving Load over 50% of Total Market 6/22 Lotte Mart High efficient drives have been installed to utilities and automation equipment in nationwide branches since 2008 and so far 23,213MWh has been saved which is the amount of annual electricity consumption for 7,700 housings. Utilities and automation equipment - Applying drives to air conditioning fans in all branches in 2008 - Applying drives to pumps in allbranches in 2010 Before Installation After Installation 15,435MWh 9,261MWh Annual Electricity ConsumptionAnnual Effect * 6,174MWh saved (40% saving) * A payback period : 2.6 years Energy Saving Cases 7/22 With ESCO funds, GM Korea had expected 3 years for pay-back and has already collected allInvestments now. Additionally, GM installed drive system for waste heat recovery/incinerator and high efficient illumination business. Utility equipment - Cooling water pump and air conditioning - 49 sets installed Before Installation After Installation * 3,049MWh saved (36% saving) * A payback period : 3 years 8,354MWh 5,305MWh Annual Electricity ConsumptionAnnual Effect Energy Saving Cases 8/22 Namhae Chemical installed MV drives in turbo blowers (fluid machinery) at sulfuric acid factory in 2009 and compound fertilizer factory in 2010 and has saved 12GWh in total. Turbo blowers (fluid machinery) - 1st : Sulfuric acid factory (3,100kW 6.6kV 1EA) - 2nd : Compound fertilizer factory(700kW 4160V 6EA) Before Installation After Installation * 11,813MWh saved (37% saving) * A payback period : 2.2 years 31,631MWh 19,818MWh Annual Electricity ConsumptionAnnual Effect Namhae Chemical (Medium Voltage) Energy Saving Cases 9/22 3,858MWh has been saved by installing MV Drive to air circulating system in the incineration plant. Air system in incineration plant - Fan(1,200kW 3300V 1ea) Before Installation After Installation * 3,858MWh saved (34% saving) * A payback period : 2.7 years Pre heater Pre heater IDF FDF 17% OPEN STACK /H 77,121S/H Inciner-ator Boiler /H 11,257MWh 7,399MWh Annual Electricity ConsumptionAnnual Effect Nowon incineration plant (Medium voltage Energy Saving Cases 10/22 1,240MWh has been saved by installing MV Drive to copper desulfurization facility. Copper desulfurization facility - Fan(500kW 6600V 1ea) Before Installation After Installation * 1,240MWh saved (46% saving) * A payback period : 2.7 years 2,693MWh 1,453MWh Annual Electricity ConsumptionAnnual Effect LS Nikko Copper (Medium Voltage) Energy Saving Cases 11/22 Energy Saving Case Paper Manufacturing H Paper Manufacturing, Cheonan Chungnam, Korea Fan Pump and Transfer Pump - Pump which supplies pulp to header box and needs to maintain constant pressure and flow regardless of input and product type -Pulper Chest Hestfor grassland process 18.5kW 5ea,22kW 3ea, 30kW 1ea, 37kW 1ea, 45kW 1ea, 110kW 2ea Annual Saving : - 1,254,638kWh(38.7% saving) Payback period - Total Investment Saving Cost Concept 2.0 years LS INV PT VALVE 100% OPEN 60% OPEN under By-Pass operation 12/22 Energy Saving Cases Glass Manufacturing H glass company, Incheon, Korea The first case of investing MV drive via ESCOcontract Application - Cooling Blower : a blower to cool a fired glass during manufacturing safety glass for vehicles

- 6.6kV 750kW2 ea Annual Saving : - 3,250,000kWh A Payback Period = Total Investment Saving Cost A MV drive installation photo 2.8 years 13/22 Energy Saving Cases Glass Manufacturing D company,Gunpo Gyeonggi-do, Korea Application/Capacity/Quantity - Dust Collecting Fan(11kW) :To collect dust and mist occurrence duringmolding process and control pressure accordingto working spots increase/decrease - Blower(15kW) : To control air volume to workers in a manufacturing line according to seasons - Others : MCB(45kW), Waste Heat Blower(22kW)2ea in total 1.3 year Manual Damper Dust Collecting Fan INV Molding Worktable Dust Collector Stack Annual Electricity Consumption - Before installation : 630,720kWh After installation : 269,370kWh Annual Saving : - 361,350kWh(57.3% saving) A Payback Period 14/22 Energy Saving Cases Car Manufacturing D Motors, Bupyeong, Korea Booth Exhaust Fan at Painting Factory Application/Capacity/Quantity -132kW- 2ea , 160kW- 2ea, 220kW- 5ea 2.3 years AHU INV INV Filter Booth Line Filter Booth Line After Installation AHU Annual Electricity Consumption - Before installation : 8,962,000kWh - After installation : 4,901,000kWh Annual Saving : - 4,231,000kWh/(47.2% saving) A Payback Period= Total Investment Saving Cost 15/22 Energy Saving Cases SA Variable Air Volume Control Buildings L Department Store, Bucheon, Korea Achieved energy saving by installing AC drives toprevious CAV(Constant Air Volume) conditioning system in case of needing to adjust air volume by times/seasons Application/Capacity/Quantity : 55kW and so forth 54ea in total SF RF INV 0 ~ 10V FROM DDC 0 ~ 10V FROM DDC RA HC CC N.O N.C INV N.C DDC CONTROLLER AHU AHU AO TEMPER-ATURE SENSOR AO 2.1 years Annual Electricity Consumption - Before installation : 3,905,208kWh - After installation : 1,409,986kWh Annual Saving : - 2,495,222kWh (63.9% saving) A Payback Period 16/22 Energy Saving Cases Annual Saving : - 464,280kWh(38.4% saving) A Payback Period Not only achieved energy saving but also solved aproblem to control optimal DO during On-Off controlling Environment Sewage Treatment Plant, Guri, Korea

Aeration Tank Surface Aerators- Surface Aerators : to supply optimal DOinside aeration tanks for purification - Electricity saving and improvement oftreated water by installing AC drives tocontrol the number of aerators revolution 55kW(Motor 11kW 4 ea) AC drive 4-sided Actual Measurement Data - Before Installation : 34.5kW(11kWx4ea) - After Installation : 17.5kW(11kWx4ea) 3.7 years MMM MMM MMM MMM MMM MMM MMM MMM Initial Settlingtank INVx1 INVx1 Normal Operation INVx1 INVx1 Initial Settlingtank AD Drive Middle speed Low Speed Operation 17/22 Energy Saving Cases Metal Processing L Cable, Korea Magnet Wire Manufacturing Wire DrawingMachine - To transfer power between wire drawing machine and motor for take up operation in magnet wire manufacturing equipment,which speed control is necessary - Previously hydraulic converter used 3.7kW 76ea in total Annual Saving : - 1,139,443kWh(81.3% saving) A Payback Period Diagram 1.6 year WireDrawing HydraulicConverter Speed ControlHandle WireDrawing Shaft Replacing LG INV 18/22 Energy Saving Cases Case Performing energy saving through HVAC system with CA (constant air) AC Drive Case Performing energy saving through coolant circulation pump with AC Drive Project PeriodAug 09 ~ Nov 09Project PeriodMar 09 ~ Jul 09 Improvement Before Operated HVAC system with constant air control type Energy loss and temperature differenceoccurred due to excessive heat supply Improvement Before Pressure difference occurred due toexcessive lift head(of fluid) of coolant supplying pump Throttle loss occurred by unnecessarily supplied pressureAfter Automatically maintains moderate temperature and realized energy saving by 68% compared to previous power consumption through variable speedcontrol system by PID of temperature controlling valve After Realized 60% energy saving throughPID setup by cutting-off inputof pressure difference side and analyzinglift head(of fluid) calculation system withinstalling pressure transmitter ondischarge side of pump Effect 614TOE/year saved 0.7years for pay-back Effect 77TOE/year saved 0.5years for pay-back HVACPump 19/22 Energy Saving Cases Case Performing energy saving through injection machine hydraulic pump with AC Drive Case Performing energy saving through dust collector(RTO) with AC Drive Project PeriodAug 09 ~ Nov 09Project PeriodSep 09 ~ Dec 09 Improvement Before Loss by drain occurred from unnecessaryflow rate other than necessary flow rateof injection machine hydraulic pumpfor each process Drain loss difference occurred by eachmold for production model Improvement Before Equipment for minimizing releasementof hazardous material by eliminating collected dust and paint which leads to throttle loss from collecting suction rate by automatic damper After Realized average 35% energy savingcompared to previous energy consumptionby supplying optimal flow rate through auto speed control system between amp for proportional control of hydraulic pump and AC Drive After Maximized energy saving by settingautomatic operation with AC Drive ofPID control signal of automatic damper Realized energy saving by 45%compared to previous system Effect 246TOE/year saved 1.6years for pay-back Effect 246TOE/year saved, 0.6years for pay-back Injection MachineDust Collector 20/22 Energy Saving Cases CaseWater treatmentCaseCooling tower Project PeriodJun 07 ~ Nov 07Project PeriodAug 07 ~ Nov 07 Improvement Before Unable to control excessive starting current and RPM due to adapting switch start system for sludge pump andcentrifugal separator Improvement Before Excessive consumption of startingcurrent by adapting switch start system and on/off control system according tobuilding temperature After Realized energy saving through setting upequipment which enables to control starting current and RPM depending onsludge amount by installing AC Drive After Realized energy saving throughcontrolling PID and starting current according to building temperature withinstalling AC Drive Effect 123TOE/year saved 1.5years for pay-back Effect 77TOE/year saved, 1.6years for pay-back Water TreatmentCooling Tower 21/22 Energy Saving Cases CaseExhaust fan applicationCaseInduction Fan (IDF FAN) application Project PeriodJul 08 ~ Dec 08Project PeriodApr 09 ~ Aug 09 Improvement Before Desulfurization exhaust fan with ratedcapacity of 400kW consumesapproximately 340kW by guide vanecontrol Excessive vibration occurs due to lack ofgas flow rate compared to rated capacity of fan Improvement Before Induction fan is operated consecutivelyregardless of incinerator in-pile pressure which causes excessive electricityconsumption Extreme in-pile pressure change due to damper control of induction fan Induction fan runs with maximum speedand lifetime depression occurs in rotary system such as bearing and impeller Rise in maintenance cost and fall in operating ratio Fall-off in equipment and workingenvironment from excessive field noise After Realized energy saving and improvedequipment environment by installing MVD After Realized energy saving, preventslifetime depression and improvedequipment environment through linked operation depending on in-pile pressureby installing MVD Effect 259TOE/year saved 2.7years for pay-back Effect 849TOE/year saved 2.38years for pay-back Iron/Steel PlantPower Generation Plant 22/22