No-load loss is a critical performance indicator for CHH Power’s distribution transformers—directly impacting grid energy efficiency and operational economics. As a constant loss, it persists whenever the transformer is connected to the power grid, regardless of load conditions (even at full no-load). Reducing no-load loss is therefore a core focus of CHH Power’s product design, aligning with global energy-saving trends and grid sustainability goals. Below is a technical breakdown of no-load loss composition, key influencing factors, and CHH’s targeted optimization approaches.
1. Definition & Significance of No-Load Loss
For CHH Power’s distribution transformers, no-load loss refers to the active power consumed when the secondary winding is open-circuited, and the primary winding is energized with a sinusoidal rated voltage at the rated frequency.
Core Characteristics
- It is a “constant loss”: Unaffected by load magnitude—only related to the voltage applied to the windings and the transformer’s core/insulation properties.
- Continuous energy consumption: As long as the transformer remains connected to the grid (even without load), no-load loss persists, making its reduction vital for long-term cost savings and carbon footprint reduction.
Economic & Environmental Impact
Transformers are foundational to power systems, and their cumulative no-load losses represent a significant portion of grid energy waste. CHH Power recognizes that minimizing this loss delivers dual value: lowering operational costs for users and reducing the power grid’s overall energy consumption.
2. Composition of Transformer No-Load Loss
CHH Power’s engineering team identifies three primary components of no-load loss, all originating from the transformer’s iron core:
2.1 Hysteresis Loss
This loss occurs due to the periodic magnetization of the core’s ferromagnetic material. As alternating current causes the magnetic field to reverse direction, the dipoles in the silicon steel sheet reorient periodically—creating a hysteresis effect that dissipates energy as heat.
2.2 Eddy Current Loss
When magnetic flux through the iron core changes, circular electric currents (eddy currents) are induced in the core, flowing parallel to the magnetic flux. These eddy currents encounter resistance in the core material, generating heat. The magnitude of this loss is tied to the core’s thickness and electrical conductivity.
2.3 Core Additional Loss
A secondary but non-negligible component, influenced by three key factors:
- Material properties: Directional characteristics of silicon steel sheets, processing-induced degradation, and the quality of insulating films.
- Design structure: Core seam type, lamination method, and overlap width of core layers.
- Manufacturing processes: Punching/shearing dimensional accuracy, burr size, handling/stacking of silicon steel sheets, and lamination quality.
3. Key Factors Influencing No-Load Performance
CHH Power’s R&D team has identified three decisive factors that shape a transformer’s no-load loss, guiding targeted design and manufacturing optimizations:
3.1 Silicon Steel Sheet Quality
The material properties of silicon steel sheets (e.g., unit loss, magnetic permeability, and directional alignment) directly determine baseline hysteresis and eddy current losses. Higher-grade sheets with lower unit loss reduce these losses but increase material costs.
3.2 Core Structure Design
Core geometry—including seam configuration, lamination stacking pattern, and magnetic flux path optimization—impacts how efficiently magnetic energy is transferred. Poorly designed cores create flux leakage and localized magnetization, elevating additional losses.
3.3 Manufacturing Process Precision
Rough processing (e.g., excessive burrs on punched sheets, uneven lamination, or damage to insulating films during handling) degrades the core’s magnetic performance, increasing all three loss components.
4. CHH Power’s Strategies to Reduce No-Load Loss
CHH Power adopts a balanced, cost-effective approach to minimize no-load loss—avoiding over-reliance on high-cost materials by combining material upgrades with structural and process innovations:
4.1 Optimized Material Selection
CHH Power sources high-performance silicon steel sheets with low unit loss (e.g., 0.23mm-thick grain-oriented silicon steel) but balances this with cost constraints. The goal is to achieve optimal loss reduction without prohibitive material expenses.
4.2 Innovative Core Structure Design
- Seam optimization: Adopts staggered or butt-joint core seams to reduce flux leakage and hysteresis loss.
- Lamination improvement: Uses precision stacking with uniform overlap widths to minimize air gaps and enhance magnetic circuit continuity.
- Flux path refinement: Designs the core to align with the directional properties of silicon steel sheets, maximizing magnetic efficiency.
4.3 Advanced Manufacturing Processes
- Precision cutting: Employs high-precision punching equipment to ensure tight dimensional tolerances and minimal burrs (≤0.02mm).
- Careful material handling: Uses automated lamination systems to avoid damaging silicon steel sheet insulating films during stacking.
- Quality control: Implements strict lamination inspections to ensure uniform density and no gaps between layers.
4.4 Cost-Effective Balance
CHH Power avoids the pitfalls of simply using the highest-grade (and most expensive) silicon steel sheets. Instead, the team prioritizes structural and process improvements—these measures reduce no-load loss while saving materials, lowering overall manufacturing costs, and delivering sustainable energy savings for users.
CHH Power’s commitment to reducing no-load loss is embedded in every stage of transformer development, from material selection to final assembly. By combining technical innovation with practical cost considerations, CHH’s distribution transformers deliver industry-leading efficiency, supporting greener, more economical power systems.