At National Grid’s HVDC converter station in Central Massachusetts, business leaders are constantly striving to maximize the facility’s uptime while keeping workers safe.

The converter station is a 2,000-megawatt facility, meaning it has around the same capacity as two typical nuclear power plants. It supplies more than 10 percent of New England’s total power, and any disruption—especially any significant period of unplanned downtime—could force National Grid to seek out costly backup sources of power to meet customers’ demands.

“It’s a very critical site for New England,” says Dean Berlin, Lead Engineer of National Grid. “If we trip offline due to a forced reason, it’s very expensive to secure other resources. It takes a lot of maintenance and effective operations tools to keep this place up and running.”

Historically, National Grid leaders have had to balance this desire for 100 percent uptime with the necessity of protecting workers from potentially hazardous equipment. For instance, no human workers can enter the station’s thyristor valve hall while it’s operating. The five-story building, which is the size of a soccer field, coverts direct current (DC) to alternating current (AC), and because of the electrical hazard posed by equipment inside the hall (and limited visibility from the outside), employees can only inspect the facility for leaks and other problems during annual scheduled downtime.

Nearly all of the projects that we do today rely on some data from Spot. The robot is providing safety benefits. Spot is a part of our team now.

Dean Berlin, Lead Engineer, National Grid

In 2019 and 2020, IT leaders at National Grid began experimenting with Spot, the quadruped robot from Boston Dynamics. At first, the tech team tested out basic operations, moving Spot through the thyristor hall to see whether the robot could merely withstand the facility’s electrical field. But over the last two years, Spot has gone from being a pilot project to an integral part of the converter station’s safety inspections.

“Nearly all of the projects that we do today rely on some data from Spot,” Berlin says. “The robot is providing safety benefits. Spot is a part of our team now.”

Regular Use

Early testing during an initial pilot phase showed that Spot could withstand the electrical field of National Grid’s thyristor valve hall. The pilot also illustrated to National Grid operators how the robot’s obstacle avoidance feature could keep it a safe distance from sensitive equipment.

After those initial tests, National Grid put fiducial markers around its site to allow Spot to monitor the grounds autonomously. The organization also beefed-up communications infrastructure, placing 14 radios around the property to create a mesh network, eliminating dead zones and ensuring that operators could maintain contact with Spot, no matter what part of the site the robot was inspecting. The radio network allows operators to interact with Spot from the site’s control room using the Orbit platform from Boston Dynamics, rather than trailing behind the robot with a handheld controller and maintaining a line of sight.

“That’s really big—being able to run Spot from our control room,” Berlin says. “You don’t have to send a human out every time you want to use the robot, even for a manual mission. The operator can sit in the control room, looking at the 20 other screens they need to monitor to keep eyes on all parts of the converter station. Spot just becomes the 21st screen.”

This flexibility allows National Grid to use Spot as part of the site’s regular inspections. While human operators make their own rounds on foot, Spot traverses the property autonomously, using an infrared camera to check for hot spots that could signal a problem with equipment. In addition to these regular inspections, operators manually walk Spot through the thyristor hall once every two weeks.

By incorporating Spot, National Grid has been able to dramatically increase the frequency of its inspections. Previously, operators inspected the thyristor hall only once each year, and infrared checks were conducted every six months.

“This station is 32 years old, and in those first 32 years, we haven’t had the ability to do those checks in the thyristor hall while it’s energized,” Berlin notes. “So, in the past, we’ve only done those inspections during planned outages. Now we have that ability to inspect inside the hall while it’s live, and that gives us more data to make better decisions as the asset ages. That data could potentially keep our facilities running for longer than originally projected.”

Peace of Mind

To accelerate adoption—and, therefore, enable Spot to become an integral part of its inspection routine—National Grid brought in Boston Dynamics for two full days of robust training sessions in early 2022. Around ten people participated in the training, including all of the operators at the converter station and several engineers.

“We covered a lot of topics, starting from the very basics about how to safely turn on the robot and how to swap out batteries,” Berlin says. “After that, we covered how to program the robot using the graphical user interface, how to run missions, and how to set up Spot with our radio network.”

By April of this year, Berlin says, operators felt comfortable enough with Spot to use the robot for automated hot spot inspections. “If we had a hot spot that wasn’t detected, a number of things could go wrong,” Berlin explains. “You could have a small event like an alarm, or you could have a catastrophic failure that leads to something like a fire or an explosion. Our biggest priority is safety. Having this extra tool to do all of these checks really helps our teams and provides peace of mind. I can go home knowing that I’ve done everything I can to get the best data possible and make the best possible decision.”

Although these regular hot-spot inspections haven’t yet turned up much out of the ordinary, Spot discovered a small oil leak on a bushing during a manual mission in the thyristor hall. Operators were able to assess the leak using a pan/tilt/zoom (PTZ) camera mounted on Spot, and they determined that the severity was “a five out of 10,” Berlin says. “It wasn’t terrible, but it was something that needed to be fixed, and we decided to schedule a planned outage based on Spot’s assessment. You never know how much worse it might get over time. Spot really helped us to make the decision.”

This station is 32 years old, and in those first 32 years, we haven’t had the ability to do those checks in the thyristor hall while it’s energized… Now we have that ability to inspect inside the hall while it’s live, and that gives us more data to make better decisions as the asset ages. That data could potentially keep our facilities running for longer than originally projected.

Dean Berlin, Lead Engineer, National Grid

Just the Beginning

As with any technology that introduces new business processes to an organization, Berlin says, implementing Spot took a fair amount of time and work. But that concerted effort was worth the outcome, he says.

“It’s very good for operators to have this additional tool,” he says. “Spot improves safety, it makes our inspections more productive, it helps us stay on top of maintenance, and overall, it gives us more data to make better decisions. So, there are many benefits. It’s important to go in with the proper perspective, though. Those first couple of years were challenging, but they were critical. People might think they can dive right in but getting the right use cases in place requires a collaborative effort.”

Because National Grid was an early adopter of Spot, Berlin says, the organization is “far ahead” of others in its industry when it comes to implementing robotics and gathering site data. And yet, he also believes that National Grid has only begun to scratch the surface of what the platform may one day make possible. Already, operators are experimenting with sensing payloads other than infrared and PTZ cameras. For instance, National Grid is looking at equipping Spot with a Fluke SV600 Acoustic Imager to detect partial discharge, as well as 3D scanning tools from Trimble.

“The future is looking very promising,” Berlin says. “Even though we’re using Spot in production, it’ll take a little more time for us to fully understand the robot’s basic capabilities. We’re not saying, ‘Okay, we’re using Spot for infrared inspections, and now we’re all set.’ It’s one platform, but we can use it for partial discharge inspections, acoustics assessments, and 3D site scanning, which could save a lot in upfront costs. And the robot is designed in such a way that you can swap out the payload in five minutes and move on to the next task.”