background image

DMC490 Microgrid Controller Software Configuration Guide 

28 

State Of Charge 

Incentive 

($/kWh2) 

This incentive promotes more charging and higher values of 

SOC.  Both 

State Of Charge Penalty

 and 

State Of Charge 

Incentive

 settings are provided to allow you more freedom to 

configure the system based on your operational knowledge.   
The cost is in dollars; for other currencies simply enter that 

value and be consistent in all fields involving the currency. 

0 to 1,000 

$/kWh2 

0 $/kWh2 

State Of Charge 

Minimum 

Penalty 

($/kWh2) 

The setting is the penalty when storage is allowed to violate its 

minimum level (that is, soft constraint is set for 

Constraint 

Mode

. The greater the violation from 

State Of Charge 

Minimum

, the greater the penalty cost in the objective 

function. 
The cost is in dollars; for other currencies simply enter that 

value and be consistent in all fields involving the currency. 

0 to 1,000 

$/kWh2 

0 $/kWh2 

Hysteresis 

The DMC490 MGC supports input up-time, down-time, and 

cycle-per-day hysteresis. When Hysteresis is On, a set of 

appropriate parameters is in place to prevent excessive 

switching and cycling. Support for hysteresis is required for 

storage input to overcome high-frequency on/off cycling of 

the electrolyzer because it lowers performance and decreases 

the life of the device. The hysteresis mostly targets the 

electrolyzer (hydrogen-based storage), but it is available for all 

storage devices. 

On 
Off 

On 

Charging 

Minimum Up 

Time (minutes) 

When the 

Hysteresis

 field is set to On, this is the minimum 

running time of the electrolyzer, in minutes.  If the electrolyzer 

is turned on, it runs for at least this length of time. When 

storage input is offline and the optimal dispatch result 

indicates storage input usage above the minimum storage 

input (

Minimum Charging Power

) for equal to or longer than 

the 

Charging Minimum Up Time

, then the storage input is 

started with the calculated setpoint. 

0 to 720 

minutes 

0 minutes 

Charging 

Minimum Down 

Time (minutes) 

When the 

Hysteresis

 field is set to On, this is the minimum off 

time of the electrolyzer, in minutes.  When the electrolyzer is 

on and receives an off command, it turns off and stays off for 

at least this length of time. 

0 to 720 

minutes 

0 minutes 

Summary of Contents for DMC490

Page 1: ...GE Grid Solutions DMC490TM Microgrid Controller Software Configuration Guide SWM0091 Version 1 00 Revision 3 GE Information ...

Page 2: ...mark Notices GE and are trademarks and service marks of General Electric Company Trademarks of General Electric Company Cisco is a registered trademark of Cisco Corporation Hyperterminal is a registered trademark of Hilgraeve Incorporated IEC is a registered trademark of Commission Electrotechnique Internationale IEEE and POSIX are registered trademarks of the Institute of Electrical and Electroni...

Page 3: ... Guide SWM0066 V5 2 D400 V5 20 online Help includes D400 configuration tool online Help How to Use this Guide For most operational features refer to the documents listed above For information specific to the Microgrid Controller MGC feature see the details provided in this manual SWM0091 The DMC490 employs sophisticated applications that contain many advanced features and capabilities To successfu...

Page 4: ...to the user May also include angle brackets around the placeholder if the placeholder is already in italic text For example c product product def References to a setting or field value shown The software related procedures in this guide are based on using a computer running Windows XP Some steps and dialog boxes may vary slightly if you are using another version of Windows Safety words and definit...

Page 5: ...pport Web site go to http sc ge com SASTechSupport Contact Technical Support The GE Grid Solutions Technical Support is open 24 hours a day seven days a week for you to talk directly to a GE representative In the U S and Canada call toll free 1 800 547 8629 International customers please call 1 905 927 7070 or email to multilin tech ge com Have the following information ready to give to Technical ...

Page 6: ......

Page 7: ...iguration Overview 18 Configure Electrical Assets 20 Configure Thermal Assets 34 Configure System Settings 40 Health Status and Monitoring 45 Chapter 3 Forecasts 46 Chapter 4 Common Forecast Settings 46 Forecasts for Renewables 47 Forecasts for Electrical Load 47 Forecasts for Grid Buy Price 48 Forecasts for Grid Sell Price 48 Forecasts for Heat Load 48 Forecast Value Update Procedure 48 ...

Page 8: ... such as diesel generators Combined heat and power CHP generation or cogeneration Heating elements such as boilers Storage specifically hydrogen based and batteries Utility grid connections The block diagram of Figure 1 shows the microgrid approach When the resources include Modbus server functionality the UR controllers are unnecessary For example when a wind turbine is added to the microgrid and...

Page 9: ... available when needed renewable sources can be better utilized when there is storage in the microgrid such as an electrolyzer fuel cell system or conventional battery storage Figure 2 shows a typical Microgrid where DG represents a Diesel Generator Figure 2 Typical microgrid Islanded Power System Operation Within any power system the generated power must match the demand The loading in the system...

Page 10: ...Figure 4 Figure 4 Isochronous control Assume that electrical and mechanical power are initially equal and speed is equal to the reference speed When the loading of the system increases then Pe becomes greater than Pm As seen in the previous equation the machine speed drops The governor takes a measurement of machine speed and compares it with a reference speed nominal speed The difference is an er...

Page 11: ...in isochronous mode and the remaining generators are operated in droop control resulting with the machine receiving an additional power signal that it compares to a power reference Figure 6 Droop control used for two or more sources of power At nominal frequency the level of power output is determined by the power reference command because the speed error signal is zero When there is a drop in fre...

Page 12: ... in non isochronous mode can pick any value between its lower and upper bounds however for an isochronous dispatchable genset lower and upper bounds of generating power need to be changed in the optimization problem solved by the MGC so that the reserve margins are respected These concepts are demonstrated in Figure 8 and Figure 9 where the highlighted regions specify the intervals that the genera...

Page 13: ...rid plus the power generated internally must equal the total load and the power exported to the grid at any instant of time The algorithm does not treat loads as dispatchable except to avoid situations of grid instability associated with imbalance between supply and demand In other words the microgrid always supplies enough power to satisfy its loads provided that this is physically possible given...

Page 14: ...ystem the contribution of renewable sources and the price of grid power if one exists Finally outputs take the form of start stop commands and power reference commands applied to generators and storage devices Generation must match load in a stable power system Dispatchable generation including the storage equals the total load minus the total power supplied by renewable sources These resources ar...

Page 15: ...d and any grid Minimum maximum and initial values of storage devices state of charge Limits on storage input and output powers The energy balance equation of storage devices representing the storage state of charge in each time step based on its value in the previous time step as well as charging and discharging powers with the consideration of the related efficiencies and standby losses When the ...

Page 16: ...icrogrid Controller Setup The Microgrid Controller is set up for microgrid operation and control from the DMC490 HMI To connect and configure a microgrid perform the following tasks 1 Set up communication between Assets controller or Asset of the Microgrid to the DMC490 using Data Collection Application see Chapter 17 Configure IED Device Blocks Clients of the SWM0066 D400 Software Configuration G...

Page 17: ...enerator is on and the user activates Legacy Off mode the diesel generator continues to operate The Analog Value code for this mode is 0 Auto On In this mode Optimization occurs and the optimal solution is communicated to the resources and assets The analog value code for this mode is 1 Advisory On In this mode Optimization occurs but the optimal solution is not communicated to the resources and a...

Page 18: ...To view the time remaining until the next cycle of Optimization is executed 1 Navigate to the MGC application Point details page on the HMI Point Summary Applications Microgrid Controller Analog Input 2 From the Analog Output access pseudo point MGC Change Current state 3 See the status for the Time to Next Advice point Configuration Overview Microgrid Assets To configure and map microgrid assets ...

Page 19: ...s that is Renewable assets Dispatchable Assets and Thermal CHP Assets 10 Configure forecast settings for optimization 11 Map the Electrical Assets and Thermal Assets status points to the Datalogger click Data Logger powerbar button so that you can analyze decisions made by the Optimizer over the logging period 12 Repeat steps 1 to 11 for each microgrid asset System Settings To configure microgrid ...

Page 20: ...ed Rated Power kW Specify the maximum power generation capacity in kW depending on the availability of the renewable resource 0 to 1 000 000 kW 250 kW Operating Cost kWh Specify the operating cost of the equipment in dollars per kWh Include operations maintenance and any fuel costs The cost is in dollars for other currencies simply enter that value and be consistent in all fields involving the cur...

Page 21: ... set by zero values Status Points The following field mappings apply to the status control and read only inputs that are to be mapped to the Microgrid controller Renewable Asset configuration page Online This field indicates if the renewable resource is online or offline Isoc Mode This field indicates if the resource is in droop or isochronous mode Net Meter Power This field indicates the power ge...

Page 22: ...can be found in the related handbooks or the Internet 0 to 1 000 kWh kg 0 55 kWh kg Start Cost Specify the cost to power up the resource Include the costs that you think are important based on your experience with the microgrid The cost is in dollars for other currencies simply enter that value and be consistent in all fields involving the currency 0 to 1 000 000 10 Stop Cost Specify the cost to p...

Page 23: ...sochronous 4 Grid in isochronous Assume in a particular microgrid one big hydro generator such as a run of the rive hydro unit with a reservoir can operate in isochronous mode This corresponds to Operation Mode 2 however any of the four operation modes can be assigned to a single hydro unit in isochronous If the operator follows the suggested operation mode assignment that is Operation Mode 2 is h...

Page 24: ...e optimizer the modes are usually the same Power Ref This field refers to the power reference points of dispatchable generators in kW Their values are computed by the MGC dispatch algorithm Operation mode This is an Analog output which refers to the current microgrid operation mode of the asset as explained in section System Settings on page 19 see the Active Mode setting Watchdog This is a Digita...

Page 25: ...Power kW Charging power for a storage device cannot be below a certain level so Specify the minimum input charging power of the storage unit This power level is related to the technology and specifications of the storage device itself and it does not depend on other dispatchable or renewable devices in the system For hydrogen storage which is interpreted as the combination of electrolyzer high pre...

Page 26: ...storage stop start or to change some input readings such as SOC This also requires defining some small regions around State Of Charge Maximum and State Of Charge Minimum Thus two regions below State Of Charge Maximum and two regions on either side of State Of Charge Minimum are defined as shown in the following figure If SOC is located in region E no action is required however if SOC is within any...

Page 27: ...mply enter that value and be consistent in all fields involving the currency 0 to 1 000 kWh 5 kWh Charging Incentive kWh This setting is the financial incentive to charge storage in dollars per kWh In some jurisdictions utilities are required to store a percent of energy and incentives can be available for such a program The incentive can be used to set this parameter for grid connected microgrid ...

Page 28: ...steresis is On a set of appropriate parameters is in place to prevent excessive switching and cycling Support for hysteresis is required for storage input to overcome high frequency on off cycling of the electrolyzer because it lowers performance and decreases the life of the device The hysteresis mostly targets the electrolyzer hydrogen based storage but it is available for all storage devices On...

Page 29: ...ed by their local controllers they have mathematical functions that calculate the maximum power depending on the value of SOC these values are published so that an external device like the DMC490 can read them Given this the DMC490 has two related settings for storage devices Charging Limit Feedback and Discharging Limit Feedback For example when the Charging Limit Feedback is Yes it means that th...

Page 30: ... this case the value read by the DMC490 is replaced with the maximum value already set by the user In other words setting value for maximum charging power is overwritten based on the value provided by the storage local controller and read by the DMC490 When the Charging Limit Feedback is set to No then the value read by the DMC490 is disregarded False True False Used by Unit Commitment1 Select yes...

Page 31: ...e fuel cell An online storage resource is not necessarily an available storage resource Net Meter Power In This is the net metered input power in kW It indicates the input charging power value read from the storage device For hydrogen storage which is interpreted as the combination of electrolyzer high pressure storage cylinders and fuel cell Net Meter Power In represents the measured value of the...

Page 32: ...t to use Point Settings Setting Description Range Default Asset ID Unique asset ID assigned by the DMC490 MGC Name Specify the name of the asset 4 to 20 characters Load Asset_ Enabled Specify if the asset is to be included in the microgrid optimization calculations Disabled Enabled Enabled Status Points The following field mappings apply to the status control and read only inputs that are to be ma...

Page 33: ... Disabled Disabled Enabled Enabled Export Enabled Specify if exporting from the microgrid to the grid is enabled This setting takes the grid contribution into the microgrid optimization calculations but only export power to the grid is allowed If both Import Enabled and Export Enabled are set to Enabled optimization calculations decide whether import power from the grid or export power to the grid...

Page 34: ...ine can also translate to having grid connection Net Meter Power This field indicates the import export power value in kW Importing This field indicates whether the grid is importing or exporting power Operation mode This is an Analog output which refers to the current microgrid operation mode of the asset as described in section System Settings on page 19 see the Active Mode setting Watchdog This...

Page 35: ...s for different fuel sources can be found in the related handbooks or the Internet 0 to 1 000 kWh kg 4 2 kWh kg Gas to Electric Ratio Specify the gas to electricity conversion ratio of the co generator For example a ratio of 0 35 means that 35 of the energy content of natural gas is converted to electricity and the remainder is in the form of heat that cannot be recovered completely For example if...

Page 36: ... can be assigned to a single co generator in isochronous If the operator follows the suggested operation mode assignment that is Operation Mode 3 is single dispatchable CHP in isochronous and Co generator 1 is supposed to be the isochronous machine the following are set for this machine Operation Mode 1 Droop Operation Mode 2 Isoch Operation Mode 3 Droop Operation Mode 4 Droop In this manner if yo...

Page 37: ...nerator The availability signal is built into the co generator s local controller based on some parameters and is read by the MGC The following field mappings apply to the AO DO control points that are to be mapped to the Microgrid controller CHP Asset configuration page Electric Power Ref This field refers to the electric power reference points of co generators in kW Their values are computed by ...

Page 38: ...generated per kg of fuel consumed Assuming the fuel to be natural gas the default value of 13 5 kWh kg translates to almost 90 efficiency considering the energy content of natural gas Calculate the number using the related curves for your boiler If the boiler efficiency is available in terms of percent this setting can simply be determined by multiplying the percent value with the higher heating v...

Page 39: ...fers to the current microgrid operation mode of the asset as described in section System Settings on page 19 see the Active Mode setting Watchdog This is a Digital Output command used to inform the asset that the MGC controller is active A Digital Output command is sent on this point with the value toggling between 0 and 1 every 10 seconds Heat Load Asset Point Settings Setting Description Range D...

Page 40: ...When connected to a grid the grid compensates for any imbalance between load and generation in the microgrid behaving like an isochronous machine for the microgrid However for islanded microgrids there is a need for an isochronous machine to maintain load generation balance and stabilize the microgrid for instantaneous load and renewable generation variations above or below the forecasted values S...

Page 41: ...rrespond to the following microgrid operation modes Configure all values The higher the variation in power generation the greater the margin 1 Dispatchable isochronous load share default 2 Renewable in isochronous 3 Single dispatch in isochronous CHP 4 Grid in isochronous For example due to the highly variable nature of solar and wind power a larger margin can be entered than for a hydro or CHP in...

Page 42: ...tch Time both of which determine the size of forecast parameters as well as decision variables for the microgrid optimization problem For each renewable grid load and heat load forecasts there are 240 registers available in the DMC490 MGC and up to 48 hours are possible as the Prediction Horizon The Dispatch Time needs to be set in conjunction with the Prediction Horizon so that the number of fore...

Page 43: ... high pressure storage cylinders and fuel cell the optimal solution is found in less than 80 seconds based on the default values for Prediction Horizon 24 hours and Dispatch Time 12 minutes 6 minutes 12 minutes 18 minutes 24 minutes 30 minutes 36 minutes 42 minutes 48 minutes 6 minutes Command Scheduler Settings Configure the startup and shutdown time intervals for Dispatchable resources and Stora...

Page 44: ...tting is the minimum delay between starting discharging storage units 10 20 30 40 50 60 seconds 10 seconds Time Interval Between Charging Shut Downs Seconds This setting is the minimum delay between stopping charging storage units 10 20 30 40 50 60 seconds 10 seconds Time Interval Between Discharging Shut Downs Seconds This setting is the minimum delay between stopping discharging storage units 10...

Page 45: ...ne of the dispatchable resources went offline unexpectedly Unexpected Disp 1 16 Online One of the dispatchable resources came online unexpectedly Unexpected Disp 1 16 in Droop Discrepancy between the Isoch command and actual reading from the device Unexpected Disp 1 16 in Isoch Discrepancy between the Droop command and actual reading from the device Unexpected Renew 1 16 in Droop Discrepancy betwe...

Page 46: ...n a Prediction Horizon of 24 hours and Dispatch Time of 12 minutes If Resolution is set to 60 minutes only 25 forecast values can be provided by the user corresponding to each hour from 00 00 to 24 00 In order to cover the forecast requirements for the whole Prediction Horizon the DMC490 interpolates the required 120 forecast values based on the 25 values provided by the user Offset Range number D...

Page 47: ...er as a coefficient between 0 and 1 When no Renewable Capability forecast is provided by the user a default value of 1 is used by the DMC490 Forecast Internal flag Specify if the forecast calculated by the DMC490 internal or another forecast is to be used external There are two options available for updating the renewable forecast information Option 1 Use the internal forecast algorithm of the DMC...

Page 48: ...Internal The MGC relies on the past 24 hours Meter measured Heat Load from the Asset Forecast Value Update Procedure The procedure for updating the Forecast information is common for Renewable Electrical Load Heat Load Grid Buy Price and Grid Sell Prices The Resolution and Offset are applicable for Load Grid Renewable and Heat Load forecasts 1 Select the appropriate values for the Resolution Offse...

Page 49: ...e first Analog Output point value is considered as the Forecasted Load for the hour at which the DMC490 clock is running Likewise the MGC issues values for the remaining 23 Analog Output points for the remaining 23 hours and then applies a Digital Output command relevant to this Forecast section ...

Page 50: ...June 14 2016 Document created 1 July 21 2016 Added map instruction step 11 to the Chapter 2 Configuration Overview Microgrid Assets Configure and map microgrid assets procedure 2 Aug 12 2016 Added subsection Using SGConfig to Configure the DMC490 to the Overview chapter 3 Aug 19 2016 Revised the About This Manual Purpose section ...

Reviews: