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“An Effective Poor Man’s “SMART” Distribution Volt/var Management System” Monday April 27 - 3:00 p.m. Tom Jauch Life Senior Member, IEEE Application Consultant - Beckwith Electric Co. Largo, FL.
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“An Effective Poor Man’s “SMART” Distribution Volt/var Management System”Monday April 27 - 3:00 p.m. Tom Jauch Life Senior Member, IEEE Application Consultant - Beckwith Electric Co. Largo, FL
“An Effective Poor Man’s “SMART” Distribution Volt/var Management System”orReaping the Benefits of Controlled Voltage Profiles(Volt / var / kW Management)Monday April 27 - 3:00 p.m. Tom Jauch Life Senior Member, IEEE Application Consultant - Beckwith Electric Co. Largo, FL
Volt / Var / kW Management Objectives • Reduce losses (kW & kvar)(even kW thru an inductance creates vars) • Increase Power Delivery Capacity • (Deliver kvars locally) • Minimize Voltage Variations(With X/R=4, kvar causes 4x Vdrop of kW) • Reduce maintenance costs • (Less tapchanges – field setting changes) • Reduce/defer capital spending • Reduce operating costs • CONSERVATION VOLTAGE CONTROL (CVC)
Volt / Var / kW Management Strategies & Methods • VOLTAGE CONTROLControl regulates bus voltages high enough so no customer ever has “low” voltage • POWER FACTOR CONTROLa) Use fixed cap banks to avoid lagging P.F. • b) Switch cap banks to maintain high P.F. • CONSERVATION VOLTAGE CONTROL (CVC)Dynamically control (minimize) distribution customer voltage levels for energy conservation
CONSERVATION VOLTAGE CONTROL (CVC) (Minimizing loads by minimizing voltages) Dynamically control (minimize) distribution customer voltage levels within 114v to 126v range Recent 3 YR Study Results: (without customer complaints!) www.rwbeck.com/neea Typical substation (average) – 1% VR reduced ENERGY (kWhr) by 0.86% 1% VR reduced KVAR load by 4% ------------------------------------------------------------------------------------
CONSERVATION VOLTAGE CONTROL (CVC) (Minimizing loads by minimizing voltages) Dynamically control (minimize) distribution customer voltage levels within 114v to 126v range Recent 3 YR Study Results: (without customer complaints!) www.rwbeck.com/neea Typical substation (average) – 1% VR reduced ENERGY (kWhr) by 0.86% 1% VR reduced KVAR load by 4% ------------------------------------------------------------------------------------ Typical substation results: Total possible energy savings = 1 - 3% Total kW demand reduction = 2 - 4% Total kvar demand reduction = 4 - 10%
Conservation Voltage Control (CVC) Results in: Immediate benefits in Gen, T & D systems Immediate reduction in generation emissions Immediate increase in generation reserves Immediate relief in customer’s bills Volt/var Management equipment is readily available
Volt/var MGMT EQUIPMENT * LTC Transformers* LTC Substation & Line Regulators* Substation Capacitor Banks* Distribution Line Capacitor Banks
Typical Voltage Control Operation Block Raise Setting Block Lower Setting
DISTRIBUTION VOLTAGE CONTROL LTC Transformer & Regulator Locations
LTC Area of Responsibility V VD=3v VD=5v VD=7v VD=2v
BUS Voltage Control Feeder Voltage Profile VD=3v BUS VD=5v VD=2v 126v VD=7v 125v 124v 122v 118v VD=7v Min Volts First customer Mid-line customer Last customer 117v Assumptions: Acceptable customer voltage = 114v to 126V Allowable minimum primary voltage = 117V
BUS Voltage Control Common Setting Practice BUS 126v VD=7v 125v 124v Regulated Voltage Range – Full Load 122v 118v 117v First customer Mid-line customer Last customer Min Volts 125v setpoint +/-1v
BUS Voltage Control Common Setting Practice BUS 126v VD=7v 125v 124v Regulated Voltage Range @ no load Regulated Voltage Range – Full Load 122v 118v 117v First customer Mid-line customer Last customer Min Volts 125v setpoint +/-1v
DistributionFeeders BUS V COMPENSATION VOLTAGE V Set 0 200 ma (CT) 0 I Conservation Voltage Control LTC Control Feature – LDC-Z LDC - Z (General Compensation) • Application: Distribution bus regulation (or CVC) • Concept: Increase bus voltage • as the load level increases • No individual line information • Uses current magnitude ONLY
BUS Conservation Voltage Control Control Setting BUS VD=7v 126v 125v 124v 122v Regulated Voltage Range @ no load 118v No load 117v First customer Mid-line customer Last customer 118v setpoint +/-1v: LDCZ=7v (No Load) + (MAX Voltage drop)
BUS Conservation Voltage Control Control Setting BUS VD=7v 126v 125v 124v Regulated Voltage Range – Full Load 122v Regulated Voltage Range @ no load 118v No load 117v First customer Mid-line customer Last customer 118v setpoint +/-1v: LDCZ=7v (No Load) + (MAX Voltage drop)
BUS Conservation Voltage Control Feeder Voltage Profile 50% Load BUS 126v VD=7v 125v 124v 50% load 122v 118v 120.5v First customer Mid-line customer Last customer 117v Conservation Setting 118.5v setpoint +/-1v : LDC-Z = 7v Common setting 125v setpoint +/-1v 3.5V Reduction = 3%
BUS Conservation Voltage Control Feeder Voltage Profile 50% Load BUS 126v VD=7v 125v 124v 50% load 122v 118v 120.5v First customer Mid-line customer Last customer 117v Conservation Setting 118v setpoint +/-1v : LDC-Z = 7v Common setting 125v setpoint +/-1v 3.5V Reduction = 3%
BUS Conservation Voltage Control Feeder Voltage Profile 50% Load BUS 126v VD=7v 125v 124v 50% load 122v 118v 120.5v First customer Mid-line customer Last customer 117v 3.5V Reduction = 3%
Di Feeder Voltage Profile With Regulator VD=3v Reduce with regs BUS New limiting condition 126v VD=7v 125v 124v Regulated Voltage Range @ FULL load VD=5v VD=2v 122v Full load 50% load 118v 117v First customer Mid-line customer Last customer 118v setpoint +/-1v LDCZ=5v
Var Control Pole top capacitor banks (SWITCHED)
Var Control GEN Basic Premise • Poletop capacitor banks are for offsetting distribution system VAr requirements • which REDUCES CURRENT • which also • reduces losses (I2R) • reduces voltage variation • reduces consequential VArs (I2X) • increases equipment capacities
Var Control THE IMPORTANCE OF PROPER CAPACITOR BANK SWITCHING !! System Effects of VArs
Var Control Important Considerations • Effects of var loads on Voltages! • Feeders: • *Feeder X/R Ratio (3 - 5) * Load Power Factor • * NUMBER OF REGULATOR TAPCHANGES ! • -------------------------------------------------------------------------------- • Substation Bus: • *Transformer X/R Ratio (25-50) * Load Power Factor • * NUMBER OF LTC TAPCHANGES !
Var Control Innovative Volt/var Management Technique Installed capacitors For unity PF
Var Control Innovative Volt/var Management Technique Control input Largest cap bank
Var Control Innovative Volt/var Management Technique Control input Largest cap bank Var Bias
Var Control Innovative Volt/var Management Technique Control input Transformer impedance
“An Effective Poor Man’s “SMART” Distribution Volt/var Management System”QUESTIONS ? COMMENTS ? Tom Jauch Life Senior Member, IEEE Application Consultant - Beckwith Electric Co. Largo, FL