The power grid is a modern engineering marvel, providing us widely available and affordable energy for not only our day to day lives, but also highly critical infrastructure elements for which we rely on personally, and as an economy.
Challenge
The power grid is a modern engineering marvel, providing us widely available and affordable energy for not only our day to day lives, but also highly critical infrastructure elements for which we rely on personally, and as an economy. However, our reliance on the grid also makes it highly susceptible to adverse events, including physical attacks. All parts of the grid can become victims of malicious events, but substations are particularly vulnerable due to their role in power distribution and the nature of their equipment.
The challenge power utilities worldwide are facing is finding an affordable solution, which can help detect, deter and facilitate an informed response to a substation security event. In the United States, this need is furthered by the physical security mandate CIP-014 issued by the North American Electric Reliability Corporation (NERC), calling for identification of security issues, vulnerability assessments and deployment of appropriate processes and systems to address. CIP-104 specifically calls for implemented security plans which include measures to deter, detect, delay, assess, communicate, coordinate and respond to potential physical threats and vulnerabilities. Fortunately, there are many solutions to help power utilities address these security concerns, one effective choice is the use of intelligent video.
Solution
Intelligent video, or video analytics, is a popular choice for the protection of critical facilities given its ability to detect, provide instant visual confirmation of the event and subsequent event forensics. The capability of this technology is increasing at a rapid rate, while decreases in hardware cost make such solutions affordable for owners or operators of critical bulk-power system sites. This case study looks at the issue of substation vulnerability and how to best use video to address, keeping in mind requirements of CIP-014. Such a system consists of fixed cameras, pan-tilt-zoom (PTZ) cameras, a deterrence device and data communication capability.
Detect
Perimeter designs can vary based on the vulnerabilities identified, aspects of the site, budget, etc. In most cases, substations can benefit from a simple “camera-following” design, which includes surveillance of a potential breach at the fence line, as well as, the ability for early detection for some distance beyond the physical perimeter. In a camera-following design, in addition to its own coverage, each camera is responsible for covering the blind spot of the adjacent camera. That camera is then responsible for covering the blind spot of the next camera, and this pairing continues around the perimeter until the final camera covers the blind spot of the first. This type of coverage design is very effective and affordable for locations with well-defined perimeters, such as substations.
Using this layout, the video feed from the fixed cameras are then enabled with video analytics algorithms to alert when predefined conditions are met. This is done by inputting the video signal into a server, edge device or NVR, located at the site, or remote to the location.
Today’s intelligent video technology provides for very specific alarm criteria, which in addition to only alarming when a target enters in a specific region, can also discriminate, or classify, by the type of target: human, vehicle, etc. Furthermore, the alarm can be restricted by specific actions taken by the target, such as loitering in an area, dropping or throwing an object, more than one target entering with a valid badge swipe (tailgating) or even the speed at which a target is entering an area. This level of discrimination provides the ability to address very specific vulnerabilities, as well as, avoid nuisance targets, such as wildlife, debris or moving vegetation.
Assess
Another key feature with significant value to substation protection is the geospatial aspects available with some video analytic solutions. This capability maps each pixel of video to its real-world latitude, longitude and elevation. This results in further assessment of the target, including the actual location, the real size of the target, the real speed and the current track. It also affords the opportunity to provide a real-time display of this information to the security operator through an easy to understand map-based user interface.
Another key assessment aspect of this substation protection scheme is the use of autonomous PTZ cameras. These are typically placed at the corners of the perimeter where they can service detections from multiple fixed cameras. As previously mentioned, geospatial video analytics, provide the benefit of knowing the exact mapbased location of the target. Knowing the location of the target is extremely valuable to the security officer, but it is also the basis for a feature known as “slew to cue,” whereby PTZ cameras armed with video intelligence can be automatically steered to the same location for instant confirmation of the target. In most cases, “slew to cue” functionality also includes an “intelligent zoom” feature, which uses the target size information from the alarm, the PTZ camera location and the target location to adjust the zoom level of the PTZ for an instant view of the target that can provide identification details (clothing color, car type, etc) without the need for the operator to further adjust the zoom.
Respond
Once a target is detected and confirmed, a security approach leveraging the use of intelligent video can continue with a coordinated response to the event. When video analytics is applied to pan-tilt-zoom cameras, it has the ability to automatically follow a defined target, freeing the operator to take other actions, such as coordinating with law enforcement officials. This feature, referred to as camera auto follow or PTZ following, can be automatically engaged as the result of a detection event, or subsequent to a slew to cue action. The system will continue to follow the target until it reaches a pre-defined system time-out, the operator takes manual control or the camera can no longer view the target. The system can then provide the resulting PTZ video as a component of the detection alarm, for a more complete understanding of the intrusion for the operator to review.
Deter
At this point, the system has detected the target, classified its type and verified it has met alarm conditions. As part of the alarm it has also included dynamic indication of its location on a map, autonomously steered a PTZ to the target to allow for gathering of more detailed target information and a PTZ has locked on and is now following the target…without any required user interaction. Total elapsed time to this point in the security response is typically less than 5 seconds.
This level of automated response addresses many vulnerabilities typically identified as part of a CIP-014 security assessment, but with minimal extra cost, it can be extended to help with the aspect of deterrence. Deterrence is often realized as a fence, physical barriers or access controlled gates. These are physical items and should certainly be included in a substation security plan.
However, another form of deterrence, which can be enabled through the use of intelligent video is the idea of audio talk down. This is the use of live or pre-recorded audio, which is activated upon an intrusion to deter the intruder. Different from a general alarm warning audio, audio talk down uses information about the location of the intruder and their actions to select appropriate pre-recorded audio to deter the intruder. Worse case, the understanding that they are being actively monitored may hasten their plan.
Coordinate
A common concern when deploying such a system is the amount of bandwidth required. Substations are almost always unmanned, which means the intrusion information must have a means to get communicated back to the main monitoring location. From a design aspect, this is typically the case, but it is important to know that it is not a requirement in order to gain security benefits from a video based system. The system described in this case study has the capability to detect, assess, respond and deter without any communication back to a main command and control. Alarms, events and system actions can be logged and stored remotely for review at a later time.
In reality, utilities will want to be notified and react in real time. In these cases, video systems can adjust to the available bandwidth – from a low bandwidth situation where a textual alarm is provided with an image of the detection, to a high bandwidth installation where feeds from multiple cameras can be monitored and controlled in real time.
In each case, complete alarm information, including meta data, images and video can be readily available to the security operations center, which can then take action based on their security response plan, including contacting and coordinating this alarm data with local law enforcement through web-based access or mobile phones.
Results
This case study outlines the effectiveness of utilizing video analytics to address the physical vulnerabilities of a typical substation. Further, the study outlines how recent technological advances allow such a solution to extend beyond the mere detection of events, but can also autonomously address assessment, response and deterrence.
Key capabilities of substation protection using intelligent video include:
- Advanced detection – Accurate alarming based on specific targets types and actions
- Situational awareness – The ability to quickly convey the critical details of a security event in an easy to understand map-based format.
- Real-time target location – Real-time location information of events and real time location tracking of potential intruders.
- Autonomous sensor control – Automated steering of cameras to an event location and subsequent hands free video tracking of a suspect.
Although each utility and substation may encounter different vulnerabilities, this case study outlines how video can be considered to address NERC guidelines for protecting critical substation assets by providing situational awareness of a potential threat and initiating an appropriate and timely response.