3750 kVA Cast Resin Dry Type Transformer

3750 kVA Cast Resin Dry Type Transformer is prepared for indoor cast-resin transformer duty. It covers 10kV / 22kV / 33kV / 35kV input networks and 2 x 690V (Split Winding) or 600V output distribution. It uses AN (Base) / AF (Forced) cooling or thermal design data where specified. This series description presents the application, construction, protection, and specification details in finished product copy.

Engineered for 3 MW Drive Systems

For indoor cast-resin transformer duty, engineered for 3 MW Drive Systems is treated as a practical design and selection point rather than generic catalog wording.

• The 3750 kVA Dry Type Transformer is a specialized capacity rating, purposefully sized to match the input requirements of 3,000 kW (3 MW) Variable Frequency Drives (VFDs) or central solar inverters. Unlike standard distribution units that feed passive loads like lights and motors, this unit serves as a critical link in power conversion systems.
• We define this unit as a specialized powerformer dry type transformer. It is built not just to step down voltage, but to interact dynamically with the non-linear switching characteristics of rectifiers. While standard transformers would overheat due to the "chopped" current waveforms drawn by a VFD, this unit features a reinforced core and winding geometry designed to withstand the high-frequency stress without derating.

35kV Class Insulation Engineering

For indoor cast-resin transformer duty, 35kV Class Insulation Engineering is treated as a practical design and selection point rather than generic catalog wording.

• Connecting large drives directly to the sub-transmission grid requires robust insulation. As a premium high voltage dry type transformer, this model is typically engineered for primary voltages of 33kV or 35kV.
• Dielectric Clearance: Operating at 35kV in a dry-type format requires expanded air clearance distances and specialized resin casting techniques. the design uses a Double-Cast process for the HV coil to ensure a void-free dielectric barrier capable of withstanding a Basic Impulse Level (BIL) of 170 kV or 200 kV.
• Surge Protection: Since high-voltage vacuum circuit breakers can cause switching overvoltages, the HV windings are reinforced with extra turn-to-turn insulation to prevent resonance failures during switching operations.

Harmonic Cancellation: Phase Shifting

For indoor cast-resin transformer duty, harmonic Cancellation: Phase Shifting is treated as a practical design and selection point rather than generic catalog wording.

• The defining technical feature of a 3750 kVA drive transformer is often its Multi-Winding Architecture.
• The Problem: Large 6-pulse drives generate severe 5th and 7th harmonic currents, which distort the grid voltage.
• The Solution: We often build this unit with two secondary windings shifted by 30 electrical degrees (e.g., Vector Group Dd0y1 ). This creates a 12-pulse system. The phase shift causes the dominant harmonics from the two secondary windings to cancel each other out at the primary side. This "clean side" effect ensures the high voltage dry type transformer does not pollute the upstream grid with harmonic noise, complying with IEEE 519 standards.

Technical Data Sheet

Technical Data Sheet provides selection data that helps compare ratings, voltage classes, and installation requirements.

• Technical Parameter.
• Specification / Options.
• 3750 kVA (Matched for ~3 MW Drives).
• 10kV / 22kV / 33kV / 35kV.
• 2 x 690V (Split Winding) or 600V.
• Dd0y1 (12-Pulse) or Dy11d0.

Typical Application Context

Typical Application Context connects the product rating with the field conditions, enclosure layout, and distribution role it is normally selected for.

• 3750 kVA dry type transformer powering VFD drives in a steel.
• Steel Rolling Mills: Feeding 3 MW main drive motors for hot strip mills. The phase-shifting design prevents harmonic torque ripples in the motor.
• Marine Propulsion: Used on electric cruise ships to power the main azimuth thrusters (pods), where dry-type construction is mandatory for fire safety.
• Solar PV Plants: Connecting to 3.X MW central inverters, stepping up 600V/800V generation to the 35kV collection grid.

Electrical and Mechanical Data

The table data is organized for quick rating comparison, project specification, and transformer selection.

Product Detail Images