Reference Application

This reference application for VOLTTRON’s OpenADR Virtual End Node (VEN) and its Simulation Subsystem demonstrates interactions between the VOLTTRON VEN agent and simulated devices. It employs a Virtual Top Node (VTN) server, demonstrating the full range of interaction and communication in a VOLTTRON implementation of the OpenADR (Automated Demand Response) standard.

The simulation subsystem, described in more detail in Simulated Subsystem, includes a set of device simulators and a clock that can run faster (or slower) than real time (using ReferenceApp’s default configuration, the clock runs at normal speed).

Eight VOLTTRON agents work together to run this simulation:

  1. ReferenceAppAgent. This agent configures, starts, and reports on a simulation. It furnishes a variety of configuration parameters to the other simulation agents, starts the clock, subscribes to scraped driver points, and generates a CSV output file. The ReferenceApp also serves as the mediator between the simulated device drivers and the VEN, adjusting driver behavior (particularly the behavior of the “simstorage” battery) while an OpenADR event is in progress, and aggregating and relaying relevant driver metrics to the VEN for reporting to the VTN.
  2. SimulationClockAgent. This agent manages the simulation’s clock. After it has been supplied with a start time, a stop time, and a clock-speed multiplier, and it has been asked to start a simulation, it provides the current simulated time in response to requests. If no stop time has been provided (this is the default behavior while the ReferenceApp is managing the clock), the SimulationClockAgent runs the simulation until the agent is stopped. If no clock-speed multiplier has been provided, the simulation clock runs at normal wallclock speed.
  3. SimulationDriverAgent. Like MasterDriverAgent, this agent is a front-end manager for device drivers. It handles get_point/set_point requests from other agents, and it periodically “scrapes” and publishes each driver’s points. If a device driver has been built to run under MasterDriverAgent, with a few minor modifications (detailed below) it can be adapted to run under SimulationDriverAgent.
  4. ActuatorAgent. This agent manages write access to device drivers. Another agent may request a scheduled time period, called a Task, during which it controls a device.
  5. OpenADRVenAgent. This agent implements an OpenADR Virtual End Node (VEN). It receives demand-response event notifications from a Virtual Top Node (VTN), making the event information available to the ReferenceAppAgent and other interested VOLTTRON agents. It also reports metrics to the VTN based on information furnished by the ReferenceAppAgent.
  6. SQLHistorian. This agent, a “platform historian,” captures metrics reported by the simulated devices, storing them in a SQLite database.
  7. VolttronCentralPlatform. This agent makes the platform historian’s device metrics available for reporting by the VolttronCentralAgent.
  8. VolttronCentralAgent. This agent manages a web user interface that can produce graphical displays of the simulated device metrics captured by the SQLHistorian.

Three simulated device drivers are used:

  1. storage (simstorage). The storage driver simulates an energy storage device (i.e., a battery). When it receives a power dispatch value (positive to charge the battery, negative to discharge it), it adjusts the storage unit’s charging behavior accordingly. Its reported power doesn’t necessarily match the dispatch value, since (like an actual battery) it stays within configured max-charge/max-discharge limits, and power dwindles as its state of charge approaches a full or empty state.
  2. pv (simpv). The PV driver simulates a photovoltaic array (solar panels), reporting the quantity of solar power produced. Solar power is calculated as a function of (simulated) time, using a data file of incident-sunlight metrics. A year’s worth of solar data has been provided as a sample resource.
  3. load (simload). The load driver simulates the behavior of a power consumer such as a building, reporting the quantity of power consumed. It gets its power metrics as a function of (simulated) time from a data file of power readings. A year’s worth of building-load data has been provided as a sample resource.

Linux Installation

The following steps describe how to set up and run a simulation. They assume that the VOLTTRON / volttron and VOLTTRON / volttron-applications repositories have been downloaded from github.

Installing and running a simulation is walked through in the Jupyter notebook in $VOLTTRON_ROOT/examples/JupyterNotebooks/ReferenceAppAgent.ipynb. In order to run this notebook, install Jupyter and start the Jupyter server:

$ cd $VOLTTRON_ROOT
$ source env/bin/activate
$ pip install jupyter
$ jupyter notebook

By default, a browser will open with the Jupyter Notebook dashboard at http://localhost:8888. Run the notebook by navigating in the Jupyter Notebook dashboard to http://localhost:8888/tree/examples/JupyterNotebooks/ReferenceAppAgent.ipynb.

ReferenceAppAgent Configuration Parameters

This section describes ReferenceAppAgents’s configurable parameters. Each of these has a default value and behavior, allowing the simulation to be run “out of the box” without configuring any parameters.

Type Param Name Data Type Default Comments
General agent_id str reference_app  
General heartbeat_period int sec 5  
General sim_driver_list list of str [simload, simpv, simstorage] Allowed keywords are simload, simmeter, simpv, simstorage.
General opt_type str optIn The ReferenceApp will automatically “opt in” to each DR events it receives from the VEN. Change this to “optOut” if the ReferenceApp should opt out of events instead.
General report_interval_secs int sec 30 How often the ReferenceApp will send telemetry to the VEN.
General baseline_power_kw int kw 500 Power consumption (in kw) that will be reported to the VTN as the baseline power that would have been consumed if there were no DR adjustment.
Clock sim_start datetime str 2017-04-30 13:00:00 Simulated clock time when the simulation begins.
Clock sim_end datetime str None Simulated clock time when the simulation stops. If None, the simulation runs until the agent is stopped.
Clock sim_speed float sec 1.0 Simulation clock speed. This is a multiplier. To run a simulation in which a minute of simulated time equals a second of elapsed time, set this to 60.0.
Load load_timestamp_column_header str local_date  
Load load_power_column_header str load_kw  
Load load_data_frequency_min int min 15  
Load load_data_year str 2015  
Load load_csv_file_path str ~/repos/volttron-applications/kisensum/ ReferenceAppAgent/data/load_an d_pv.csv ~ and shell variables in the pathname will be expanded. The file must exist.
PV pv_panel_area float m2 1000.0  
PV pv_efficiency float 0.0-1.0 0.75  
PV pv_data_frequency_min int min 30  
PV pv_data_year str 2015  
PV pv_csv_file_path str ~/repos/volttron-applications/kisensum/ ReferenceAppAgent/data/nrel_pv _readings.csv ~ and shell variables in the pathname will be expanded. The file must exist.
Storage storage_soc_kwh float kWh 450.0  
Storage storage_max_soc_kwh float kWh 500.0  
Storage storage_max_charge_kw float kW 150.0  
Storage storage_max_discharge_kw float kW 150.0  
Storage storage_reduced_charge_soc _threshold float 0.0-1.0 0.80 Charging will be reduced when SOC % > this value.
Storage storage_reduced_discharge_s oc_threshold float 0.0-1.0 0.20 Discharging will be reduced when SOC % < this value.
Dispatch positive_dispatch_kw float kW >= 0.0 150.0  
Dispatch negative_dispatch_kw float kW <= 0.0 -150.0  
Dispatch go_positive_if_below float 0.0-1.0 0.1  
Dispatch go_negative_if_above float 0.0-1.0 0.9  
Report report_interval int seconds 15  
Report report_file_path str $VOLTTRON_HOME/run/simulation_out.csv ~ and shell variables in the pathname will be expanded. If the file exists, it will be overwritten.
Actuator actuator_id str simulation.actuator  
VEN venagent_id str venagent  

Driver Parameters and Points

Load Driver

The load driver’s parameters specify how to look up power metrics in its data file.

Type Name Data Type Default Comments
Param/Point csv_file_path string   This parameter must be supplied by the agent.
Param/Point timestamp_column_header string local_date  
Param/Point power_column_header string load_kw  
Param/Point data_frequency_min int 15  
Param/Point data_year string 2015  
Point power_kw float 0.0  
Point last_timestamp datetime    

PV Driver

The PV driver’s parameters specify how to look up sunlight metrics in its data file, and how to calculate the power generated from that sunlight.

Type Name Data Type Default Comments
Param/Point csv_file_path string   This parameter must be supplied by the agent.
Param/Point max_power_kw float 10.0  
Param/Point panel_area float 50.0  
Param/Point efficiency float 0.75  
Param/Point data_frequency_min int 30  
Param/Point data_year string 2015  
Point power_kw float 0.0  
Point last_timestamp datetime    

Storage Driver

The storage driver’s parameters describe the device’s power and SOC limits, its initial SOC, and the SOC thresholds at which charging and discharging start to be reduced as its SOC approaches a full or empty state. This reduced power is calculated as a straight-line reduction: charging power is reduced in a straight line from reduced_charge_soc_threshold to 100% SOC, and discharging power is reduced in a straight line from reduced_discharge_soc_threshold to 0% SOC.

Type Name Data Type Default Comments
Param/Point max_charge_kw float 15.0  
Param/Point max_discharge_kw float 15.0  
Param/Point max_soc_kwh float 50.0  
Param/Point soc_kwh float 25.0  
Param/Point reduced_charge_soc_threshold float 0.8  
Param/Point reduced_discharge_soc_threshold float 0.2  
Point dispatch_kw float 0.0  
Point power_kw float 0.0  
Point last_timestamp datetime    

VEN Configuration

The VEN may be configured according to its documentation here.

Running the Simulation

There are three main ways to monitor the ReferenceApp simulation’s progress.

One way is to look at debug trace in VOLTTRON’s log output, for example:

2018-01-08 17:41:30,333 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: 2018-01-08 17:41:30.333260 Initializing drivers
2018-01-08 17:41:30,333 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         Initializing Load: timestamp_column_header=local_date, power_column_header=load_kw, data_frequency_min=15, data_year=2015, csv_file_path=/home/ubuntu/repos/volttron-applications/kisensum/ReferenceAppAgent/data/load_and_pv.csv
2018-01-08 17:41:30,379 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         Initializing PV: panel_area=50.0, efficiency=0.75, data_frequency_min=30, data_year=2015, csv_file_path=/home/ubuntu/repos/volttron-applications/kisensum/ReferenceAppAgent/data/nrel_pv_readings.csv
2018-01-08 17:41:30,423 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         Initializing Storage: soc_kwh=25.0, max_soc_kwh=50.0, max_charge_kw=15.0, max_discharge_kw=15.0, reduced_charge_soc_threshold = 0.8, reduced_discharge_soc_threshold = 0.2
2018-01-08 17:41:32,331 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: 2018-01-08 17:41:32.328390 Reporting at sim time 2018-01-08 17:41:31.328388
2018-01-08 17:41:32,331 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         net_power_kw = 0
2018-01-08 17:41:32,331 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         report_time = 2018-01-08 17:41:31.328388
2018-01-08 17:41:32,338 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:                 Setting storage dispatch to 15.0 kW
2018-01-08 17:41:46,577 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: Received event: ID=4, status=far, start=2017-12-01 18:40:55+00:00, end=2017-12-02 18:37:56+00:00, opt_type=none, all params={"status": "far", "signals": "{\"null\": {\"intervals\": {\"0\": {\"duration\": \"PT23H57M1S\", \"uid\": \"0\", \"payloads\": {}}}, \"currentLevel\": null, \"signalID\": null}}", "event_id": "4", "start_time": "2017-12-01 18:40:55+00:00", "creation_time": "2018-01-08 17:41:45.774548", "opt_type": "none", "priority": 1, "end_time": "2017-12-02 18:37:56+00:00"}
2018-01-08 17:41:46,577 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: Sending an optIn response for event ID 4
2018-01-08 17:41:46,583 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: 2018-01-08 17:41:46.576130 Reporting at sim time 2018-01-08 17:41:46.328388
2018-01-08 17:41:46,583 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simload/power_kw = 519.3
2018-01-08 17:41:46,583 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simpv/power_kw = -17.175
2018-01-08 17:41:46,583 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/dispatch_kw = 15.0
2018-01-08 17:41:46,584 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/power_kw = 15.0
2018-01-08 17:41:46,584 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/soc_kwh = 25.025
2018-01-08 17:41:46,584 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         net_power_kw = 49.755
2018-01-08 17:41:46,584 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         report_time = 2018-01-08 17:41:46.328388
2018-01-08 17:41:46,596 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:                 Setting storage dispatch to 15.0 kW
2018-01-08 17:41:48,617 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: Received event: ID=4, status=completed, start=2017-12-01 18:40:55+00:00, end=2017-12-02 18:37:56+00:00, opt_type=optIn, all params={"status": "completed", "signals": "{\"null\": {\"intervals\": {\"0\": {\"duration\": \"PT23H57M1S\", \"uid\": \"0\", \"payloads\": {}}}, \"currentLevel\": null, \"signalID\": null}}", "event_id": "4", "start_time": "2017-12-01 18:40:55+00:00", "creation_time": "2018-01-08 17:41:45.774548", "opt_type": "optIn", "priority": 1, "end_time": "2017-12-02 18:37:56+00:00"}
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: 2018-01-08 17:42:59.559264 Reporting at sim time 2018-01-08 17:42:59.328388
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simload/power_kw = 519.3
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simpv/power_kw = -17.175
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/dispatch_kw = 15.0
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/power_kw = 15.0
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/soc_kwh = 25.238
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         net_power_kw = 49.755
2018-01-08 17:42:59,563 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         report_time = 2018-01-08 17:42:59.328388
2018-01-08 17:42:59,578 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:                 Setting storage dispatch to -1.05158333333 kW
2018-01-08 17:43:01,596 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: 2018-01-08 17:43:01.589877 Reporting at sim time 2018-01-08 17:43:01.328388
2018-01-08 17:43:01,596 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simload/power_kw = 519.3
2018-01-08 17:43:01,596 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simpv/power_kw = -17.175
2018-01-08 17:43:01,597 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/dispatch_kw = -1.05158333333
2018-01-08 17:43:01,597 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/power_kw = -1.051
2018-01-08 17:43:01,597 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         devices/simstorage/soc_kwh = 25.236
2018-01-08 17:43:01,597 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         net_power_kw = 33.704
2018-01-08 17:43:01,597 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:         report_time = 2018-01-08 17:43:01.328388
2018-01-08 17:43:01,598 (referenceappagent-1.0 23842) referenceapp.agent DEBUG: Reporting telemetry: {'start_time': '2018-01-08 17:42:31.598889+00:00', 'baseline_power_kw': '50', 'current_power_kw': '33.704', 'end_time': '2018-01-08 17:43:01.598889+00:00'}
2018-01-08 17:43:01,611 (referenceappagent-1.0 23842) referenceapp.agent DEBUG:                 Setting storage dispatch to -1.0515 kW

Another way to monitor progress is to launch the VolttronCentral web UI, which can be found at http://127.0.0.1:8080/vc/index.html. Here, in addition to checking agent status, one can track metrics reported by the simulated device drivers. For example, these graphs track the simstorage battery’s power consumption and state of charge over time. The abrupt shift from charging to discharging happens because an OpenADR event has just started:

../_images/2-simulation-out.png

A third way to monitor progress, while there is an active DR event, is to examine the event’s graph in the VTN web UI. This displays the VEN’s power consumption, which is an aggregate of the consumption reported by each simulated device driver:

../_images/3-simulation-out.png

Report Output

The ReferenceAppAgent also writes a CSV output file so that simulation results can be reported in a spreadsheet, for example this graph of the simulated storage device:

../_images/4-simulation-out.png

For Further Information

If you have comments or questions about this simulation support, please contact Rob Calvert or Nate Hill at Kisensum, Inc.: