Remote Access to Substation Devices

Access to substation devices (IEDs, RTUs) for utility engineers and technicians who are not physically present at the substation is vital to grid operations. Currently, engineers/technicians perform much of their work remotely from workstations or laptops, typically over dial-up modems and other ad-hoc means. At the same time, non-critical administrative access to the substation devices is also required for the management of the substation. With the installation of a Cisco WAN / Substation network, these communications can be unified, made secure, and compliant to NERC/CIP reporting.

Substation device and gateway vendors can validate end-to-end connectivity over Cisco wide area and substation networks and interoperability with Cisco Connected Grid products in the substation, to build customer confidence in the joint solution with the “Cisco Compatible” certification and logo.
To get started, join the Cisco Developer Network for Connected Energy (CDN/CE):
http://developer.cisco.com/web/partner/getstart

Background

The SCADA engineers/technicians both actively and reactively monitor and adjust substation devices based on load and supply at a particular substation.
However, this has the following limitations:
  • Information flow is often slow; RTUs periodically poll various substation devices and collect data to be analyzed by backend systems. No intelligent processing occurs at this point.
  • Back office systems poll RTUs for data across typically low speed links with significant latency, with as much as second+ delay.
  • Workstations/laptops are limited to slow dial-up connections prone to drops and disconnects hampering the engineers/technicians from performing routine duties, remediation, or emergency activities in a timely manner.
  • Connectivity via dial-up modems and 1-MB line(s) is both costly and problematic. Providers mandate costly electrical isolation equipment at ingress to each substation for each line.
  • NERC-CIP reporting requirements of who connected to which device, when and for how long, and what operations were performed during the session are often not met.
This lack of automated information in the substation and the delayed reactive exchange to the backend systems and eventually to engineers/technicians leads to operating inefficiencies (errors, delays, and reduced work capacity).  
 
Cisco Substation Automation technologies allow for new real-time data and information access to the state of substation and distribution assets. Providing this information in a proactive manner to backend systems and personnel in the field makes them more productive and the grid more stable.

Solution Description

Direct engineering access to a substation device may be facilitated via the device’s command line interface using Secure Shell (SSH) or a similar network protocol. Figure 1 below illustrates this configuration. 
 
Figure 1 Remote Direct Access to Substation Devices
 
At the substation, the device may be connected directly to a Cisco Connected Grid Switch (CGS) via Ethernet, to a Cisco Connected Grid Router (CGS) via its serial interfaces, or to a substation gateway device via its serial interfaces.
 
A gateway is a substation communication server that provides one or more of the following for substation devices: data concentration, protocol translation, automation logic, event file collection, password management, Human-Machine Interface (HMI), and enterprise connectivity. Figure 2 illustrates at high level, how devices can be accessed via substation gateways.
 
Figure 2 Remote Access to Devices via Substation Gateways

Solution Testing

Solution integration testing will typically consists of the following steps:

  1. Define test plan
    1. Functional test cases
    2. Performance test cases
    3. NERC/CIP reporting test cases
  2. Physical connection of the devices and network
  3. Network configuration
    1. WAN setup and configuration
    2. Substation network setup and configuration
    3. Substation Gateway(s) setup and configuration (if applicable)
    4. Device(s) setup and configuration
  4. Virtual LAN, VPN, and QoS configurations
  5. Execute test plan
More information on suggested test plans, equipment configurations, etc. is available to Cisco Developer Network for Connected Energy (CDN/CE) members. Here is where to get started.
http://developer.cisco.com/web/partner/getstart