“A lot of work has been done”: MAI professor talks about a unique domestic kinetic storage device

— Konstantin Lvovich, what is a superconducting kinetic energy storage (KNE)?

What is this device?

— KNE is necessary for the accumulation and storage of energy.

This is primarily an autonomous uninterruptible power supply.

KNE is able to equalize the load schedule in the power grid, smooth out power fluctuations and provide the most optimal operating modes for a particular equipment.

The prototype of the product, which was created by the MAI team, has no analogues in Russia.

A lot of work has been done to integrate a number of truly unique solutions into the design of a superconducting kinetic storage ring.

And most importantly, we know how best to apply KNE and mass-produce it.

Let me explain: the principle of operation of a kinetic storage device is that it converts the mechanical energy of a rotating flywheel into the electrical energy of a motor-generator.

The peculiarity of the design of our kinetic accumulator is that it allows minimizing electrical and mechanical losses, as well as getting rid of the friction of the rotating parts against the air, which makes it possible to achieve an efficiency of 99.99%.

Structurally, our kinetic accumulator consists of a flywheel, an electric motor, which, in fact, sets the flywheel in motion, bearings and magnets.

What is a flywheel?

In childhood, everyone played with Yula.

And she spun for a long time due to the fact that the contact between her and the table surface was minimal.

In the energy storage device, the role of the top is played by the flywheel.

During the operation of the CNE, it spins up, stores kinetic energy, and then converts it into electrical energy.

In order for the flywheel to work non-stop, to accumulate, store and transfer energy as efficiently as possible, it is necessary to minimize friction, practically eliminate it.

This is exactly what was done.

It is clear that aerodynamic losses (air resistance) are easily removed when the flywheel is placed in a vacuum - for this, the so-called evacuated housing was made.

Much more difficult was the case with mechanical resistance in bearings.

To solve this problem, in our device, the effect of storing the magnetic flux by hard superconductors of the second kind was applied when they are cooled in the presence of a magnetic field.

• Superconducting kinetic energy storage (SEC)

• © Postgraduate student of the department 310 MAI Vladimir Podguzov

To put it simply, MAI engineers have developed a technology for organizing a non-contact magnetic suspension using high-temperature superconducting bearings.

So we were able to cope with the mechanical friction of the bearings.

"Magnetic support" was also created for such a massive product as a rotor.

Thanks to her, it was possible to increase the rigidity of the bearings.

That is, the mass that rotates in the CNE has remained the same, and the weight of the impact on the bearings has become minimal.

This idea was taken from nuclear power.

In addition, we removed the hysteresis losses in the motor-generator.

Our team was able to make the so-called "ironless" unit.

Of course, there are metal parts in it, they just do not respond to magnetic fields.

In our CNE, unlike other similar devices, energy costs are needed, by and large, only for cooling magnetic bearings.

— And how long ago did the MAI begin to deal with magnetic suspensions?

— We started working on magnetic “supports” about 20 years ago.

The work started after receiving an order for the development of a technology for high-speed transport on a magnetic suspension.

She did not find practical application due to the high cost.

However, this project made it possible to obtain superconducting non-contact bearings, which I mentioned above.

In addition to us, the topic of magnetic suspensions is dealt with by MSTU.

Bauman and MPEI (Moscow Power Engineering Institute. -

).

Actually, the employees of these universities took part in the development of the new KNE.

From the side of the MAI, scientists from the department 310 "Electric power, electromechanical and biotechnical systems" worked on the product.

— In what way is the MAI kinetic energy storage inferior and in what way is it superior to products with the same functionality?

“In terms of its functionality, the CNE is close to a lithium-ion battery, which is now widely used in various fields to provide uninterrupted power supply.

This type of battery has gained worldwide popularity due to the relative ease of operation.

However, it has many significant shortcomings.

These are, as a rule, low specific energy intensity, a small number of charge-discharge cycles, a limited service life, explosion hazard, and the lack of a proven environmentally friendly disposal technology.

• Professor Konstantin Kovalev and postgraduate student of the Department 310 MAI Vladimir Podguzov (one of the members of the development team)

• © MAI

The lithium-ion battery is excellent for use in mobile phones.

However, in satellites, vehicles, and even more so in the energy sector, power supplies are required that will operate under heavy loads and for a very long period of time.

Of course, you can install lithium-ion batteries that have a resource for tens of thousands of discharge-charge cycles, but this will be a very heavy device.

KNE may be larger, but it is lighter and practically devoid of restrictions on the number of charge-discharge cycles - these are literally tens of millions of units.

In addition, it is absolutely environmentally friendly, safe and does not require a control system.

From my point of view, the kinetic storage is more effective than a lithium-ion battery as an emergency or backup power source.

Also, KNE allows to extend the life of ground-based power plants and spacecraft with solar panels.

For example, the maximum service life of a modern Earth remote sensing satellite is seven years, but in reality it works even less - literally two or three years.

A satellite charges and discharges twice a day.

If you calculate, then for the maximum service life (seven years) there is a little more than 5 thousand discharge-charge cycles.

To extend the life of the satellite, you can put a heavier lithium-ion battery on it.

But, of course, this will entail an increase in the weight and size characteristics of the spacecraft and, most likely, will complicate its launch into orbit.

— In what other areas can KNE be applied?

- The range of application of kinetic power storage devices is very wide.

If we talk about it as an emergency power source, then it makes sense to use it in data centers, nuclear power plants, medical institutions, chemical and metallurgical industries.

In fact, KNE is required by any organizations and enterprises where it is critical to prevent power outages.

In the event of a power failure, the kinetic storage device will be able to provide consumers with electricity until the backup source is turned on.

Now diesel generators are mainly used as a backup source.

It takes a certain amount of time to launch them.

According to the regulations, this is usually 10 minutes, but at low temperatures, the launch period can be significantly longer.

• Laboratory of Department 310 "Electric power, electromechanical and biotechnical systems" MAI

• © MAI press service

KNE is also convenient as a compensator for peak power consumption, that is, it provides additional energy with a sharp increase in electricity consumption.

The third direction is the recovery (receipt, return) of energy in transport systems.

What is this about...

When the car slows down and accelerates, kinetic energy is generated, which can be stored with the help of a flywheel (located on the axis of the chassis) and, for example, used when the vehicle is moving uphill.

In the current realities, CNE may well be integrated into the mechanisms of hybrid cars and electric buses instead of batteries, which sooner or later will have to be disposed of somehow.

It seems to me that the kinetic storage device can make a significant contribution to strengthening the power of airborne radar stations (RLS), electronic warfare equipment (EW) and laser installations.

— At what stage is the implementation of the KNE project?

- To date, a prototype of the device has been created, and our immediate goal is to fine-tune the prototype to a product that can be sent for trial operation.

We look forward to integrating the kinetic storage tank as an emergency power source at nuclear power plants.

At the end of last year, the MAI team presented a project for a superconducting kinetic energy storage device at the European Conference on Applied Superconductivity EuCAS - 2021. The report aroused great interest among foreign audiences.

Europeans are aware of the importance of such technologies in energy and data centers.

But our priority goal is the development of the project on the Russian market, especially in the context of import substitution.

Now we feel interest from industrial enterprises that are interested in regulating peak electricity consumption.

Moreover, this interest is “hot”, that is, it requires urgent, urgent decisions.

If there are relevant agreements, then we are ready to resolve issues on the organization of the production of CNE under the terms of reference of consumers.

— Is it possible to organize serial production of KNE?

— Yes, it is real, although there are certain difficulties.

In particular, now there is a problem with the manufacture of massive superconductors in the Russian Federation.

So far, these products can be produced in small quantities by MSTU.

Bauman and SuperOx company.

But increasing the scale of production of massive superconductors, as I think, is a completely solvable issue.