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GNSS helping Synchrophasors keep Power Grids Stable

As we have started converting more wind, solar and other forms of energy to electricity, there is more supply that ever available previously.  Similarly we are also consuming more power than ever. Electric cars for example consume a lot of energy. In addition we have more electronic gadgets that we keep connected to chargers, regardless of weather they need charging or not. 

At every instant of time, the power fed in the grid has to be consumed or stored somewhere. In addition, it has to be ensured that the amplitude, frequency and phase remains constant. This is where Synchrophasors come into play. The video below, explains it in a simple way what they are: 

u-blox has a nice write-up on this topic explaining why this is important. 

Improvements in terms of timing accuracy have come in lock-step with improvements in positioning accuracy. The u‑blox F9 GNSS receiver platform, which brought scalable and affordable high precision positioning – down to the decimeter-level – to the mass market, also greatly improved timing accuracies, using a new generation of multi-constellation, multi-band high accuracy GNSS receivers. This has made five nanosecond timing accuracy for absolute time – even less for relative time –  available to industrial applications at a fraction of the cost of wired timing and synchronization solutions.

One application with increasingly demanding timing needs is the power grid. A growing proportion of our power is produced using highly intermittent sources such as wind and sunlight. At the same time, the applications that we are powering are changing too, from predominantly resistive loads (that extract work through resistive heating, for example) to capacitive loads (that extract work via a capacitor, as used to convert from AC to DC).

These changes make managing power grids more challenging. For one, grid managers need to ensure that, at each instant, the power fed into the grid is consumed somewhere. When passing clouds and gusts of wind can dial up and down power production from one instant to the next, this is far from obvious. Then, capacitive loads (like inductive loads, the third of the cohort) lead to a phase shift between voltage and current, which, in turn, can lead to instabilities that have to be managed.

That’s why synchrophasors, also referred to as phase management units, have become indispensable in modern power grids. Synchrophasors monitor the phase across portions of the power grid to detect the onset of system-wide oscillations that could threaten the grid’s stability. To extract meaningful data, the synchrophasor’s sampling frequency needs to be higher than the grid’s 50 Hz pulse, and it has to be synchronized to all other sychrophasors with microsecond-level relative timing accuracies.

But what if there’s a bug, e.g. a short circuit, in the power grid that shuts down a portion of the network? Being able to locate the fault is vital to bringing service back up quickly. The more accurately it can be located, the more targeted the intervention by the service technicians will be. 100 nanosecond relative timing accuracy between adjacent traveling wave detectors is sufficient to pin down faults to within 30 meters. 

Wireless timing and synchronization is gaining traction in a growing number of industrial verticals. Fast production lines in smart factories need tight synchronization, as do data networks in time-sensitive financial applications such as high-frequency trading. GNSS-enabled wireless timing offers an easy-to-deploy, low-cost timing solution that is traceable to coordinated universal time (UTC).

More details here.

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