How to Explain Our- Side-of-the-Meter Topics to Customers Moreкод для вставки
How to Explain OurSide-of-the-Meter Topics to Customers More Effectively Topic #1: Power Factor Correction & Costs Topic #2: Why Utilities Have Interconnect Rules for Solar & Wind Power Topic #3: Dealing With Power Quality вЂњOffendersвЂќ Affecting Other Customers Managing Power Factor (p.f.) вЂў What is it? вЂ“ Ratio of real power to apparent power used in an AC power system вЂў Causes of low power factor вЂ“ Motors, fluorescent lights .anything with coils of wire and many electronic devices. вЂў Why does the utility care? вЂ“ Bad things can happen economically and physically if p.f. is not managed and controlled вЂў Power factor improvement options вЂ“ Generation modification, Capacitors, VAR Compensators Electrical Power вЂў The rate of work that can be accomplished. вЂў There are 3 Types of Electric Power вЂ“ Real Power (Watts, Kilowatts (kW), Megawatts (MW)) вЂ“ Apparent Power (Volt-Amps, Kilovolt-Amps (kVA), Megavolt-Amps (MVA)) вЂ“ Reactive Power (Volt-Amps, Kilovolt-Amps Reactive (kVAR), Megavolt-Amps Reactive (MVAR)) вЂў Apparent Power = Real Power + Reactive Power вЂ“ Kind ofвЂ¦вЂ¦..Using Vectors/Vector Math and Trigonometry. Real Power (kW) What is Power Factor? вЂў Ratio of Real to Apparent Power in a circuit вЂў Given as % or decimal equivalent вЂў Circuit with 90% (0.9) power factor; 100% Power Factor Voltage Current Time No Lag вЂ“ 90% is real (kW) вЂ“ 10% is reactive (kVARs) вЂў Indication of the timing between the volts and amps in an AC system. Power Factor < 100% Voltage Current Time Lag What Causes Low Power Factor? вЂў Inductive LoadsвЂ¦.things with coils of wire inside using magnetic fields to operate. вЂ“ Motors вЂў Motor oversizing; oversized motors have low power factor вЂў Lots of small motors; small motors tend to have low power factor вЂ“ Fluorescent lights вЂў High efficient lighting ballasts can have high or low power factor depending on the quality вЂ“ Solenoid operated equipment вЂў Operations with lots of these devices that operate for long periods can have low power factor. Why Do Power Suppliers Care вЂў Economics вЂ“ Match revenue and costs more closely by customer вЂў Some customers may have power factor penalties and some may not. вЂ“ Reduce power/line losses in the distribution system вЂў Reliability вЂ“ Improve voltage regulation due to reduced line loss/voltage drop What is the potential impact to the company if you donвЂ™t measure all the power each customer uses??????? Why Is This So Confusing? вЂў Power factor causes a disconnect between our billing and equipment sizing jargon. вЂў Most people donвЂ™t like vector math. вЂў Real Power (kW or MW) is used as a billing term вЂ“ Induction meters ($12) can only measure real power вЂ“ Historically needed multiple meters and $$$$$$$$$ to measure apparent power вЂў Apparent Power (kVA or MVA) is used as an equipment sizing term вЂ“ The transformer and components must be sized large enough to handle ALL the power going through itвЂ¦.or it will fail. вЂ“ It makes sense to size the equipment for the total (apparent power) and not just the real or the reactive part that makes it up. Analogies People Use вЂў In an attempt to explain power factor people use all kinds of different analogies Apparent Power (kVA) вЂ“ Pulling Wagon вЂ“ Sailboats вЂ“ Beer & Foam вЂ“ Water Wheel Reactive Power (kVAR) Real Power (kW) But What Is It?????? вЂў Deviation in the timing of the change of direction between the volts and amps in an AC electrical system having coiled wires (motors and fluorescent lights). вЂў The magnetic field produced in a coil of wire (motor windings, fluorescent ballasts) causes the current (amps) to slow down in relation to the pressure (volts) in an AC electrical system. 100% Power Factor Voltage Current Time No Lag Power Factor < 100% Voltage Current Time Lag Power Factor Improvement/Correction вЂў Need to speed the electrons/amps back up in relation to the voltage. вЂў Electron Speeder Uppers (technical term) otherwise known as Power Factor Correction вЂ“ GenerationвЂ¦.Some generators can be вЂњadjustedвЂќ to produce slightly more or less real and reactive power вЂ“ TransmissionвЂ¦.Capacitor banks can be added to the transmission system by the owner. вЂ“ DistributionвЂ¦..Capacitor banks can be added to the distribution system by the owner вЂ“ CustomerвЂ¦вЂ¦Capacitors and/or VAR compensators can be added to the electrical system by the customer. Economics of Power Factor Correction вЂў What charges/penalties do I pay the power supplier for low p.f.? вЂў What does it cost me in equipment and installation cost to correct? вЂў How fast do I break even? вЂў What are the other benefits I may receive? вЂ“ Power Supplier вЂў Better voltage regulation and reliability вЂў Lower line losses that can save money вЂ“ Customer вЂў Better voltage вЂў Cooler motors that run longer вЂў Cooler lighting systems that last longer How to Explain Our-Side-of-theMeter Topics to Customers More Effectively Topic #1: Power Factor Correction & Costs Topic #2: Why Utilities Have Interconnect Rules for Solar & Wind Power Why We Have Interconnection Rules & Procedures (Helping consumers understand) The highway system for vehicles 1. The вЂњelectric highwayвЂќ system (grid) 2. Rural Electricity Resource Council Wilmington, Ohio Any system with more than one user, needs rules. Traffic laws for the highway Interconnection rules for the grid This protects the system for everyone. вЂњRules of the RoadвЂќ (transmission vs. distribution) Some paths are large to handle large volume of cars. Others are small to handle a lesser flow. Same with grid and flow of electricity. вЂњRules of the RoadвЂќ Traffic needs to flow one way on some paths, and the opposite way on other paths. Electric Transmission & Distribution Large Lines and Smaller Lines Power plants: the "heart" of the system. вЂњRules of the RoadвЂќ To вЂњconnectвЂќ there are required ways to enter and exit. For highway: Must also use safe methods to вЂњconnectвЂќ. For grid: Inverter Wind Disconnect Wind Service Energy Panel Meter How to Explain OurSide-of-the-Meter Topics to Customers More Effectively Topic #1: Power Factor Correction & Costs Topic #2: Why Utilities Have Interconnect Rules for Solar & Wind Power Topic #3: Dealing With Power Quality вЂњOffendersвЂќ Affecting Other Customers Sometimes customers need help understanding power suppliers donвЂ™t and canвЂ™t provide perfect power Caught in the Middle вЂў What happens when one customer causes electrical problems for another customer? вЂў The power supplier is caught in the middle. вЂў Power quality disturbances can be very short in timeвЂ¦.but cause all kinds of operational problems with electronic equipment. Is this a вЂњgrounded serviceвЂќ Neighbor As Source вЂў The utility distribution system can simply provide a path for a problem at one location to move and show up at another location. вЂў Common power quality problems originating at a neighboring customer location include: вЂ“ Phase Voltage Unbalance вЂ“ Voltage sags from startup of large inductive loads вЂ“ Waveform distortion including harmonics and line notching. вЂ“ Excessive neutral to earth voltage from high neutral current flow/faults returning to the utility system from improperly grounded equipment. SERVICE 1 FAULT CURRENT NEIGHBORING SERVICE SERVICE 2 FAULT CURRENT FAULTY WATER PUMP Short Term Voltage Fluctuations (Sags, Swells & Flicker) вЂў Sag Voltage Sag (+) Less than 1 minute Voltage вЂ“ Voltage falls between 10 and 90% of nominal вЂў Swell вЂў If itвЂ™s long enough, you notice lights dimming or getting brighter. вЂў Sags are much more common than swells (-) Time Voltage Swell (+) Less than 1 minute Voltage вЂ“ Voltage rises to between 110% and 180% of nominal (-) Time Swell Trip Example вЂў A gas processor is complaining to the power supplier about frequent tripping of a compressor motor. вЂ“ The facility had recently undergone an equipment upgrade where electronic control and protection equipment replaced traditional protection equipment. вЂў The compressor might trip off 3 or 4 times a day or go several days without a trip. вЂ“ Monitoring at the power supply point showed numerous short term swell events on the electrical system caused by a neighboring customer starting a large motor. вЂ“ When contacted for assistance, the electronic control equipment representative indicated the trip adjustments should not be modified because the motor would not be protected вЂњas wellвЂќ. Power Quality Monitoring The Solution вЂў Voltage varies outside of ANSI C84.1 (normal) levels for fractions of a secondвЂ¦.not seconds or minutes. вЂ“ Current power supplier standards really donвЂ™t address this well. вЂў Adjust the trip settings on the new electronic controls from their extremely sensitive factory settings to more reasonable settings seen in the вЂњreal worldвЂќ. вЂ“ The factory trip setting was + 5% for any length of time longer than 6 cycles (0.1 second). вЂ“ Motor standards allow + 10% continuously. вЂў Changing the settings to + 10% for 5 seconds (max) allowed the equipment to ride through the вЂњeventsвЂќ caused by the neighbor that were considered вЂњunusualвЂќ but within the realm of вЂњnormalвЂќ operation. Transients (Spikes) вЂў Distribution System вЂў Breakers вЂў Capacitors & Transformers Impulsive Transient (+) Voltage вЂ“ Lightning вЂ“ Switching Operations вЂ“ Fault Clearing/Breaker Operations вЂў Customer System вЂ“ Lightning вЂ“ Arcing Devices вЂ“ Starting & Stopping Motors вЂ“ Breaker Operations вЂ“ Capacitor Switching (-) Time (seconds) Transient Example вЂў A small machine shop is complaining to the power supplier about spikes measured at the meter coming from the distribution system. вЂў A VFD manufacturer has replaced the same 250 Hp drive three times in the last year and has finally said вЂњno more drives under warrantyвЂќ. вЂ“ Each failure is a problem with the electronics on the circuit boards exhibiting classic signs of overheating from вЂњspikesвЂќ according to the drive manufacturer. вЂў Monitoring by the drive company shows an occasional 3,000 volt transient that occurs from very few to thousands of times a day coming in at the service. The Problem/Solution вЂў A welding shop Вј mile down the road has an automatic welding process they occasionally run. вЂ“ When the welding machine strikes an arc, a high voltage transient is created that propagates along the distribution system. вЂ“ They also have a grounding problem. вЂў The Solution: вЂ“ The shop experiencing the problem added Transient Voltage Surge Suppression at the service and the problem with the drives disappeared. Waveform Distortion вЂў A steady state deviation from an ideal sine wave of power frequency principally characterized by the spectral content of the deviation. вЂў There are several types of waveform distortion: вЂ“ Harmonic Distortion вЂ“ Line Notching вЂ“ Noise вЂ“ Frequency Fluctuations вЂў The most вЂњdiscussedвЂќ of these in the recent past is Harmonic Distortion. 1990вЂ™s Harmonic Enforcement Example вЂў A power supplier is getting multiple complaints from residential customers in rural areas near oil company installations of submersible pumps operated by VFDвЂ™s вЂ“ Electronic equipment exhibits multiple operation problems and resets/reboots frequently. вЂ“ Equipment manufacturers says the equipment is working fine when brought in and checked at the shop. вЂ“ Checks by the utility show large amounts of harmonic distortion exceeding IEEE 519 standards levels on the utility system. вЂ“ Customers are also complaining about frequent static on the rural phone system to the extent the phone is un-usable. The Solution вЂў The power supplier manager writes a letter to the oil companies (5 largest revenue customers) and politely asks them to add filters to their VFD installations to eliminate the harmonics on the system. вЂ“ The oil companies supply diesel generators and diesel to the neighboring customers in an attempt to get everyone off their back. вЂ“ The FCC eventually steps in and tells the utility manager вЂњshut them off to clean up the phone systemвЂќ. вЂ“ A judge sides with the FCC when the utility manager hesitates. вЂ“ The oil companies install the necessary filters on their drives after a couple of years of everyone being frustrated. 2000вЂ™s Enforcement Example вЂў Harmonics produced by VFDвЂ™s in a chemical plant in NM are causing occasional shutdowns of automatic oilers on a natural gas compression station down the road. вЂў The utility measures THD in excess of IEEE 519 standards and immediately tells plant management they cannot operate their VFDвЂ™s until they can comply. вЂў The chemical plant loses several hundred thousand dollars in revenue during the shutdown waiting for filters to be installed on the drives so they can commence operation. 2010вЂ™s Enforcement Example вЂў A major oil companies variable frequency drives are causing a harmonics problem for a neighbor....a large natural gas pipeline. вЂ“ The automatic oiling devices on the pipeline compressor trip off and shut down the pipeline compressor adversely impacting pressure on the pipeline. вЂў The oil company has been a consistent source of harmonic distortion in the past that is causing problems for the power suppliers AMR system. вЂ“ The power supplier must schedule shutdowns of the customerвЂ™s equipment before the AMR system will read the meters on that distribution line. The Solution вЂў The power supplier manager has been told by state officials shutting the offending company off until compliance is gained would not be acceptable. вЂў The power supplier manager places a large switch at the offending customers service that monitors harmonics produced by the customer and disconnects the service вЂњtemporarilyвЂќ to protect the neighboring customers equipment. вЂў The closest service center is 40 miles away and a вЂњreconnect feeвЂќ is charged each time the power supplier must reconnect the switch to restore power. вЂў The switch opens 12 times in the first weekвЂ¦..the customer decides to fix the problem.