Cold Rolled Non-Grain Oriented Silicon Steel
The Core Material Driving High-Efficiency Generators

In modern industry, generators serve as the "heart" of energy systems—their performance directly influences the efficiency of energy conversion. As global energy efficiency standards rise (e.g., IEC 60034-30-1's mandates for IE4/IE5 efficiency levels), material innovation has become a key driver of advancements in generator technologies. Among numerous material upgrades, Cold Rolled Non-Grain Oriented Silicon Steel (CRNGO) has emerged as a critical enabler due to its low magnetic anisotropy (<10%) and excellent magnetic properties. Its random grain orientation technology effectively mitigates multi-dimensional magnetic path losses in rotating machines. This article explores CRNGO’s technical characteristics and its application in next-generation generators. 

Generator Structure and Working Principle

Generators convert mechanical energy into electrical energy and consist mainly of a stator and rotor. The stator is fixed within the casing, housing both windings and core; the rotor rotates via bearings and is powered by either permanent magnets or electromagnetic coils. When an external current is applied, a rotating magnetic field is formed between the rotor and stator. Using the principle of electromagnetic induction, this setup transforms mechanical input into electricity.

Crucially, the three-dimensional rotating magnetic field imposes stringent demands on the core material: it must sustain high magnetic flux density while minimizing losses across multiple directions. CRNGO addresses these challenges through precise control of random grain orientation (anisotropy <10%), which boosts permeability uniformity by over 40% compared to conventional materials—making it ideal for generator operation.

Generator core structure

Generator core structure

CRNGO vs CRGO

Parameter
CRNGO
CRGO
Magnetic Anisotropy
Low (<10%)
High (>90%)
Core Loss Factors
Depends on grade, thickness, flux density (B), and operating temperature
Also influenced by manufacturing processes
Magnetic Induction
Measured as B<sub>50</sub> or B<sub>5000</sub>
Measured as B<sub>8</sub> or B<sub>100</sub>
Typical Applications Motors, generators, EV traction motors Transformers, reactors, inductors

Global Grade Examples

CRNGO Popular Grades:

  • China (Baosteel): B15AV1000 (0.15mm), B30AV1500 (1.63T), B35APV1700 (1.68T)

  • International: JFE JNEH series (0.15mm), ASTM M-45, EN M800-50A, IEC 800-50A

CRGO Popular Grades:

  • China (Baosteel): B23G110, B27G120, B35G145

  • International: JIS 30P120, ASTM M-6, EN 120-30P, IEC 110-27P

Technical Breakthroughs in Generator Applications

  1. High-Frequency Response & Ultra-Thin Development
    The demand for 0.15mm ultra-thin CRNGO is growing, driven by compact, high-speed and servo motor needs. For instance, Baosteel’s B15AV1000 achieves ≤10.0 W/kg loss at 50Hz, 1.6T—ideal for transformers, motors, and generators.

  2. Low Core Loss + High Magnetic Flux Balance
    High-flux steel is critical for boosting generator efficiency. Baosteel B35APV1700 offers 1.68T induction and ≤17.0 W/kg loss, improving wind turbine system efficiency by 2–3%.
    Japan’s 20JNEH1200 (12W/kg) is popular for compact and intermittent-duty motors, especially in EVs.

  3. Low Noise and Reliability Optimization
    In precision and noise-sensitive applications, low magnetostriction matters. Baosteel B27APV1400 achieves ≤0.94μm/m, cutting mechanical vibration and noise by 5–10dB.
    ThyssenKrupp’s M330-35A, with stacking factor ≥0.95, reduces eddy currents and improves stability.

Global Grades and Application Mapping

Country
Grade
Thickness (mm)
Core Loss (W/kg @50Hz)
Magnetic Flux (T)
Typical Application
China
Baosteel B20AV1300
0.2013W/kg1.63Electricity, electronics and appliances
Japan
20JNEH12000.2012 W/kg 1.62 Electric motor, transformer and other electrical equipment core
Europe
M330-35A (Thyssen)
0.353.3 W/kg 2.9 Electromagnetic cores
USA
M15-24G
0.362.4 W/kg 1.6 High-frequency motors, compact motors
South Korea
20PNF1500
0.20
15 W/kg
1.62
EV motors, high-frequency electronics, efficient motors

Application Scenarios and Solutions

Wind Turbines

  • Challenge: Turbulent airflow changes magnetic flux directions frequently

  • Solution: Baosteel B35AV1700

  • Outcome: Annual power output increase of 120,000 kWh over conventional steel

EV Traction Motors

  • Challenge: High RPM (>20,000) intensifies skin effect

  • Solution: JFE 20JNEF1500

  • Outcome: 35% expansion in motor efficiency >97% zone (MAP)

Moopec: Your Trusted Materials Partner

Moopec specializes in high-performance material sourcing and selection services. We offer a full range of CRNGO and CRGO silicon steel grades backed by Baosteel, along with advanced processing capabilities such as lamination, cutting, and punching for generator applications.

What We Offer:

  • Material Consultation & Technical Support: Expert advice on optimal grade selection based on client needs

  • Processing & Value-Added Services: In-house lamination, core cutting, and disc stacking services for production readiness

  • End-to-End Quality Assurance: From raw material procurement to final delivery, with full QC reports

  • Fast Response & Delivery: Efficient supply chain support for just-in-time delivery and production agility

Our 0.15mm ultra-thin CRNGO achieves ±2μm thickness tolerance—helping customers boost generator power density by 5–8% annually.

The Key Material Behind Next-Generation Generators
Non-Oriented Silicon Steel