7/27/2019 Application Note-Peak Shaving Mode AGC 3

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AGC 3.x with ASW 3.5x.x Application NoteSetting up Peak Shaving Operation

27 April, 2010

ENABLING THE SYSTEM FOR PEAK SHAVINGPeak shaving utilizes a combination of Load Dependent Start/Stop functionality in the AGC Gen Set controls plus theDay and Night settings of the AGC MAINs. The functionality uses the concept of spinning reserve or how much loadis on the system versus how much power is available from the generator set running. Additional generator sets arestarted in order to maintain the spinning reserve setpoint.

1.) PEAK SHAVING POWER FLOW DETECTION 2 METHODSa. Utilize a transducer (TAS-331 DG) and connect to AGC Gen Set control or AGC MAINs Multi-Input

102.i. The transducer range is programmed into the AGC Gen Set control by setting Multi-Input #

102 as a 4 to 20 mAdc input (menu 10980).ii. The transducer range is programmed into AGC MAINs Transducer Ranges; menus # 7003 &

# 7004.b. Utilize an AGC MAINs with CTs and PTs connected.

i. When an AGC MAINS is used the Transducer Range needs to be 0 (# 7003, # 7004).ii. The AGC MAINS Day and Night setpoints (menus 7001 and 7002) become the transducer

range or how what the kW production the MAINs is. It also defines what the Peak Shavingsetpoint will be after the plant kW becomes greater than the values in menus 7001 or 7002.

iii. As load is added to the system, the AGC MAINs will control the Peak Shave kW level to thesetpoint entered into # 7001 and #7002.

2.) PLANT HOURS of OPERATIONa. The AGC MAINs has the feature to define DAY and NIGH hours.

i. Two different menus, # 7011 and # 7012 are used to define the daytime hoursii. Two different menus, # 7013 and # 7014 are used to define the night time hours.

b. Most generation plants have only one Peak Shaving setpoint.i. The AGC MAINs Day & Night setpoints (# 7001 & # 7002) are set equal.

3.) START 1 st GEN SETPOINTa. The AGC Gen Set and AGC MAINs calculate the difference between the AGC MAINs Day or Night

settings (menus # 7001 or # 7002) minus the AGC Gen Set Load Dependent Start setpoint (# 8001)to know when to start a gen set.

i. DAY setting = (value in #7001) minus Load Dependent Start ( # 8001)ii. NIGHT setting = (value in # 7002) minus Load Dependent Start (# 8001)

4.) STOP LAST GEN SETPOINTa. The AGC Gen Set and AGC MAINs controls calculate the difference between the AGC MAINs Day or

Night settings (menus # 7001 or # 7002) minus the AGC Gen Set Load Dependent Stop setpoint (#8011) control to know when to stop the gen set.

i. DAY setting = (value in #7001) minus Load Dependent Stop ( # 8011)ii. NIGHT setting = (value in # 7002) minus Load Dependent Stop (# 8011)

5.) STARTING AND STOPPING ADDITIONAL GEN SETSa. The system will use the Load Dependent Start (# 8001) and Load Dependent Stop (# 8011) setpoints

in the AGC Gen Set controls ONLY to determine when to start and stop additional units.b. For stopping of the last gen set, the AGCGen Set Stop Generator setting (# 7031) is used.

6.) MINIMUM LOAD CARRIED BY GEN SET with PRIORITY 1a. The minimum load or the lowest power production Priority 1 gen set will carry or deload to equals the

AGC Gen Set control Minimum Load setpoint(#8005).b. When the AGC controls are In AUTO Mode, the generator set GBs open only when the control is

instructed to stop and perform a deload operation.

7.) EXAMPLEa. AGC MAINs system is used

7/27/2019 Application Note-Peak Shaving Mode AGC 3

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AGC 3.x with ASW 3.5x.x Application NoteSetting up Peak Shaving Operation

27 April, 2010b. AGC MAINS Setpoints

i. Day & Night (# 7001 & 7002) = 400 kWii. Transducer Range (# 7003, # 7004) = 0

c. AGC Gen Set Setpointsi. Load Dependent Start (# 8001) = 175 kWii. Load Dependent Stop (# 8011) = 175 kWiii. Minimum Load ( # 8005) = 25 kW

d. AGC Mains will be the sole system providing power when less than 400 kW is on the bus.e. When load has been added to the system resulting in equal to or less than 175 kW spinning reserve

from the AGC MAINs, the gen set with priority #1 will start to provide power.f. Priority #1 gen set will carry additional load until there is equal to or less than 175 kW left available to

provide by this gen set.g. At this juncture, gen set with priority # 2 will start and take over.h. This process of adding generators or spinning reserve capacity will repeat itself following these

calculations.i. When load is decreased to more than 175 kW of unused power available (spinning reserve) the gen

set with the lowest priority will shutdown per the processes programmed within the AGC (De-Load,Open GB, Cooldown,, Extended Stop, etc.)

j. This gen set shutdown/shed process will continue until there is more than 175 kW of unused power

available (spinning reserve) of gen set with priority #1.k. Gen Set with priority #1 will shutdown when the spinning reserve is more than the AGC MAINs

Day/Night setpoint (# 7001/# 7002) plus the AGC Gen Set control Minimum Load setpont (# 8005).