An Arc Suppression Coil (ASC), also known as a Petersen coil, is a specialized inductive reactor used in medium-voltage electrical networks to ground the system’s neutral point. Its primary purpose is to compensate for capacitive charging currents that occur during single-phase earth faults.

Makitel designs and manufactures high-performance autotransformers engineered for highly efficient voltage regulation and grid decoupling across medium-voltage networks. Unlike conventional isolation transformers, these units utilize a single, continuous winding shared between the primary and secondary circuits.

Makitel stands at the absolute pinnacle of green grid engineering, delivering an elite portfolio of high-efficiency eco-design transformers optimized to meet the planet's most stringent environmental demands. Manufactured under the Makitel brand at their cutting-edge European facility, these premium units are engineered in strict compliance with the European Tier 2 low-loss standards.

By incorporating revolutionary materials and advanced electromagnetic core geometries, Makitel sets a new global benchmark for energy conservation, combining ultra-high electrical efficiency with uncompromising operational reliability.

MAKITEL DOOEL designs and manufactures highly specialized, custom-engineered transformers specifically tailored for the rigorous demands of the naftenic and oil-pumping industries.
50-Position Mobile Regulation Systems: Engineered for flexible oil-pumping deployments, these advanced mobile units feature an extensive regulation span on the low-voltage (LV) side offering 50 unique regulation positions (utilizing a 25-position tap changer combined with a Delta-Wye / Star-Delta switchable connection

MAKITEL DOOEL  designs and manufactures high-performance power and distribution transformers equipped with advanced On-Load Tap Changers (OLTC). This technology enables seamless, dynamic voltage regulation and tap shifting during active operation (on-load), completely eliminating the need to de-energize the transformer or interrupt power delivery to connected consumers.

Integration of Premium Vacuum Technology: To ensure ultimate reliability and minimal maintenance, MAKITEL integrates top-tier vacuum tap changers sourced exclusively from globally renowned, industry-leading manufacturers. By quenching the electrical arc inside hermetically sealed vacuum interrupters rather than in the transformer oil, these premium components eliminate oil carbonization, drastically extend service intervals, and maximize contact lifespan.

Smart Grid and Industrial Regulation: These OLTC-equipped transformers are engineered for both distribution networks facing volatile load swings and industrial plants with strict voltage tolerance requirements. Whether integrated into automated Smart Grid systems or managed via localized voltage regulators, MAKITEL’s OLTC units dynamically compensate for high-voltage transmission line fluctuations, maintaining a stable, constant secondary output voltage to safeguard downstream equipment.

Built and tested according to rigorous international IEC standards, MAKITEL's on-load regulating transformers deliver unmatched grid stability, operational flexibility, and long-term network efficiency.

1. Multi-Tap and Multi-Voltage HV Systems: Flexible Grid Adaptation

Modern transmission and distribution networks often require a single substation node to interface with varying regional overhead line voltages or adapt to ongoing grid modernizations. MAKITEL addresses this complexity by engineering transformers equipped with specialized off-circuit or on-load tap changers linked to multiple primary taps.

Dual/Multi-Voltage Flexibility: These systems are designed with split or multi-tap high-voltage (HV) windings that allow the transformer to switch between different high-voltage levels (e.g., shifting between 10 kV, 20 kV, or 35 kV systems). This ensures that a single unit can be seamlessly redeployed or adjusted as the surrounding grid infrastructure evolves.

2. Stabilizing Windings: Open and Closed Delta Configurations

In transformers where both the primary and secondary windings are connected in a star configuration with an accessible neutral point (Yn-Yn), grid operators face challenges related to triplen harmonics and unbalanced loads. MAKITEL engineers integrate a third (tertiary) stabilizing winding into the core design, operating in two modes:
Closed Delta (Δ): This auxiliary winding provides a closed path for third-harmonic (3rd harmonic) currents to circulate freely.

This eliminates harmonic distortion within the magnetic flux, ensuring a clean sinusoidal voltage wave and drastically reducing supplementary core losses. It also acts as a balancer during severe phase-to-phase load unbalances.

Open Delta (for Protection): This configuration is utilized to connect voltage-monitoring and relay protection equipment. Under normal, balanced grid conditions, the sum of the three phase voltages in the open delta is zero. However, when a phase-to-ground fault (earth fault) occurs in the grid, the symmetry is disrupted. A residual voltage (zero-sequence component) appears across the open terminals, instantly triggering the relay protection to isolate the fault.

3. Rectifier Solutions for Heavy Industry (Multi-Phase Systems)

Industrial plants, metallurgical operations (such as furnace transformers, which are part of MAKITEL’s specialized product lineup), and high-power DC systems require clean power with minimal harmonic distortion. The company builds rectifier transformers featuring specific vector groups:
12-Pulse Rectifier Transformers: These units feature a single primary winding and two independent secondary windings wound on the same core leg. One secondary winding is connected in Star (Y), while the other is connected in Delta (Δ).

Harmonic Cancellation via Phase Shifting: The inherent difference between the Y and Δ connections introduces a natural 30° phase shift between the two secondary voltages. When these two systems are connected to bridge rectifiers, the highly disruptive 5th and 7th harmonics cancel each other out on the primary side. For more advanced 24-pulse or 48-pulse industrial systems, MAKITEL implements additional Zig-zag (Z) windings to achieve ultra-precise, custom phase-shifting angles.

4. Specialized Transformers for Battery Energy Storage Systems (BESS)

The rapid expansion of renewable energy sources and large-scale battery storage units for grid stabilization has driven demand for split-winding transformers. MAKITEL provides cutting-edge solutions featuring multiple independent windings on the low-voltage (LV) side:
Multi-Secondary Construction: A single transformer tank houses two, three, or four isolated LV windings wrapped around the same core leg. Each winding connects to a dedicated inverter from the battery storage array (BESS) or a localized solar PV field.

Galvanic and Magnetic Isolation: The windings are structurally and axially separated inside the tank. This strict decoupling prevents the formation of circulating (loop) currents between parallel-operating inverters. Furthermore, the high short-circuit impedance between the individual secondaries ensures that if a fault occurs in one battery block, it remains isolated, preventing a total system shutdown.

5. Multi-Purpose Transformers with Varying Secondary Capacities
For modern Smart Grids, where a single substation node must simultaneously manage diverse consumers and producers (prosumers), MAKITEL custom-projects transformers with windings featuring entirely different nominal capacities (Sn=Sn1+Sn2+,,,+Sn(n)) and different secondary voltage levels.