A Korean research team has successfully developed an electronic overcurrent circuit breaker using a new concept current sensor module that measures electromagnetic waves. This sensor, essential for implementing smart factories, is currently being transferred to relevant companies and commercialized.

The Electronics and Telecommunications Research Institute (ETRI) announced on the 23rd that it has developed the world's first non-coil current sensor module that measures electromagnetic waves.

It is expected to be effective in blocking overcurrent in places that handle large amounts of electricity.

A current sensor module is a device that measures the current flowing in a power wire in an electronic overcurrent circuit breaker. Until now, the methods for detecting current have mainly used heat or magnetic fields.

On the other hand, existing methods had several limitations, such as not being able to measure current within a specific range, having large errors, and slow measurement speeds.

Especially in the case of large-scale factories that consume a lot of electricity, it is necessary to quickly detect and cut off the power when a short circuit occurs.

If the sensor detects it too late and current is transmitted, the equipment may malfunction or a fire may occur, resulting in property damage and loss of life.

Unlike conventional methods, the research team used ‘electromagnetic waves.’

This is a method of measuring electromagnetic waves generated around the power induced by placing wires and sensor lines parallel to each other in a circuit.

The developed sensor module can measure currents in both large and small ranges, but the research team experimentally confirmed that it can measure induced currents even when high currents of up to 800 amperes (A) are applied.

Because it uses a non-contact method that measures using electromagnetic waves, power loss is minimal and the device can be manufactured in extremely small sizes, measuring just a few millimeters (mm). The associated low manufacturing costs also make it advantageous for mass production.

In particular, since it utilizes electromagnetic waves rather than heat, the measurement speed is also five times faster. When using a strong magnetic field during short-circuiting, it is measured at a maximum of 20 ms (millimeter seconds).

On the other hand, if a fully electronic circuit breaker is made with this sensor, it can measure within a minimum of 4 ms, enabling safe power cutoff.

Based on the current sensor, the research team also created an intelligent module that processes programs to remove noise around the sensor, transmit current values for Internet of Things (IoT) communication, cut off power, etc., and an overload relay for motor control.

Users can also freely develop systems that include the functions they want.

The research team explained that this achievement made it possible to create a dream circuit breaker, a 'fully electronic power circuit breaker.'

In addition, the developed module can be used anywhere that uses alternating current.

In particular, it is expected to be effectively utilized in current monitoring systems, power circuit breakers, and overcurrent protection for DC-AC power converters in homes, factories or base stations requiring high current, and electric vehicles.

The idea for the sensor wire came from research into how to block power using heat-driven metal-insulator transition (MIT) devices.

The research team stated that they were able to achieve this result thanks to the experience and know-how accumulated through over 20 years of MIT phenomenon identification, material component, and semiconductor-related research.

ETRI researcher Kim Hyeon-tak said, “We expect this technology to serve as a model case for developing core smart factory technologies for the Fourth Industrial Revolution.”

According to a global market research firm, the global industrial current sensor module and application system market is expected to grow at an average annual rate of 5.65%, reaching a global market size of KRW 43 trillion by 2025.

This technology was developed by the Ministry of Science and ICT It was carried out as a project titled ‘Development of source technology for rapid charge/discharge low-voltage switching elements for mobile terminals.’

The research team's technology was transferred to Dong-A Electric Industrial Co., Ltd.