China claims superiority over West with DC warship power system

However, AC has high requirements for motor operation and coordination, according to a report by the South China Morning Post (SCMP). The rotational speeds of multiple motors must match. If they don’t this can affect the stability of the ship’s grid.

According to the SCMP, several relatively new western warships use AC power, and this has caused issues including total electrical failures. These include Britain’s Type 45 destroyers and America’s Zumwalt-class destroyers.

“China has taken the lead in the field of integrated power systems (IPS) for ships,” lead project scientist Rear Admiral Ma Weiming wrote in a peer-reviewed paper published in the Proceedings of the CSEE (Chinese Society for Electrical Engineering).

Its DC technology is “one generation ahead” of its competitors, he continued.

The IPS converts all primary energy sources of a ship into electrical energy. This is then used for propulsion, communication, navigation, weapons, and other operational requirements.

AC versus DC

According to the researchers behind the new IPS system, western navies aim to transition to DC technology, but this won’t happen until 2027 at the earliest.

China long ago chose to use DC IPS rather than going the IPS route, like many other nations. With DC systems, the direction of current remains constant, enabling a stable voltage. This makes generator coordination easier, and it also makes power grid reconstruction much faster in the event of a fault occurring. 

These are just a few of the reasons that Thomas Edison was such a firm supporter of DC power grids during his lifetime. Edison, who is credited as having invented the light bulb, lost the famous “war of the currents” to Nikola Tesla in the late 1800s. At the time, DC motors and power grid transmission technologies were seen as much harder to scale.

According to Ma’s team, Chinese engineers and scientists have solved many of the problems that put people off DC in the past. 

So the transition to DC for warships might be seen as a vindication of sorts for Edison, though it could give Chinese warships a serious advantage over the US, if Ma’s team is to be believed. 

Last year, Ma and his team proposed a nuclear “super warship”, for example, using DC IPS. It would boast an electromagnetic missile launcher, rail guns, and laser weapons. Even Edison and Tesla would have found it hard to imagine such technologies when they were disputing their “war of the currents”.