Cosimulation Introduction

Simulation Models (1/3)

• Markets
• Transmission
• Distribution
• Devices
• Communication
• Controls
• Loads

Simulation Models (2/3)

• Transient
• Dynamic
• Steady-State
• Planning

Simulation Models (3/3)

• Technical
• Economic
• Techno-economic

Solutions

• Simplify models
• Bigger Computer
• Co-simulation

What is co-simulation?

• Execution of multiple distinct simulation objects together in coherent fashion
• Co-simulation is used whenever a single simulator is insufficient to answer the relevant questions

Why co-simulation?

• Lots of effort has gone into (sub) domain-specific tools. (So use them)
  • Trusted by stakeholders
  • Continue to improve
• Allows focus on the “glue-ware”
  • Faster prototyping for research
  • Many frameworks
• Encourages Modularity
  • Swap models as needed

HELICS

Capabilities:

• Scalable: 2-100,000+ Federates
• Cross-platform: HPC (Linux), Cloud, Workstations, Laptops (Windows/OSX)
• Modular: mix and match tools
• Minimally invasive: easy to use lab/commercial/open tools
• Open Source: BSD-style.
• Many Simulation Types:
  • Discrete Event
  • QSTS
  • Dynamics
• Co-iteration enabled: “tight coupling”

HELICS Interfaces to key domain simulators

Cosimulation of Electrical Grid, Thermodynamics of Houses, and Control Systems

Architecture of Cosimulation (1/2)

Architecture of Cosimulation (2/2)

Terminology

• Federate - An individual simulator that is computing something interesting and communicating with other simulators
• Core - An object managing the interactions of one or more federates
• Broker - An object coordinating multiple cores or brokers:
  • There can be several layers of brokers
• Root broker - The root broker in the hierarchy
  • Last chance router
  • Responsible for determining when to enter initialization mode for the federation
• Federation - The set of all federates executing together in a single co-simulation