Abstract: Based on the operating characteristics of agricultural transformers, this paper proposes technologies such as selecting economical operating modes, choosing energy-saving transformers, and appropriately controlling operating voltage to reduce losses and save energy. Keywords: Agricultural distribution transformer, loss reduction technology 1. Rational Selection of Transformer Capacity The economic efficiency of transformer operation is one of the important factors to consider when rationally selecting transformer capacity. Analysis shows that when the load loss Pk of the transformer equals the no-load loss Po, the power loss of the transformer is minimized and the operating efficiency is highest. For transformers below 1000kVA, manufacturers generally design them with a load factor within the economic operating range of 40% to 60%, i.e., the most economical operation is under half-load conditions, while the economic efficiency is extremely poor under light load or no-load conditions below 30% of the rated capacity. Given the prominent characteristics of agricultural distribution transformers, which have relatively low load factors, adjustable capacity transformers can be used when conditions permit, allowing the transformer to operate within the economic operating range as much as possible, which is a method to reduce transformer losses. 2. Selection of Energy-Saving Transformers According to the State Economic and Trade Commission's document [2002] No. 112, the S11 type wound core transformer has advantages such as simple winding process, light weight, small size, 25% to 30% lower no-load loss than S9, convenient maintenance, lower operating costs, and significant energy-saving effect. It is well-suited to the load characteristics and technical requirements of China's rural power grid, and its use should be actively promoted in rural power grid construction and renovation projects. The S9 series 10kV power transformer is currently the lowest-loss product produced in China. Compared with the S7 series, its no-load loss can be reduced by 10%, and its load loss can be reduced by 10%, resulting in significant energy savings. It is currently a common product for rural power grid renovation. Amorphous alloy core transformers are currently the least energy-saving transformers. Their no-load loss can be reduced by an average of 75% compared to S9 transformers of the same capacity, and by 78% compared to S7 transformers. However, their price is higher than the S9 series transformers. But the price difference between the two types of transformers can be offset by the reduced electricity costs within 5 to 7 years due to the reduced losses. Therefore, it should be given priority in areas where conditions permit. 3. Appropriately control the grid operating voltage to reduce the no-load loss of distribution transformers. The total loss of a distribution transformer is: As can be seen from the above formula, the fixed loss of a distribution transformer is proportional to the square of the distribution network operating voltage. Since the iron loss (no-load loss) of the distribution transformer accounts for 80% of the total loss, it is necessary to ensure that the voltage deviation of end users is within the allowable range. During off-peak agricultural electricity consumption, the operating voltage of the agricultural grid should be appropriately reduced, and during peak agricultural consumption, the operating voltage of the agricultural grid should be appropriately increased. 4. Adjust the three-phase balance of the transformer in a timely manner . According to regulations, the current imbalance at the outlet of the distribution transformer is generally required to be no greater than 10%, the imbalance at the beginning of the main line and branch lines should be no greater than 20%, and the neutral line current should not exceed 25% of the rated current. This is because in the distribution system, some phase currents are small, while others are close to or even exceed the rated current. In this case, it not only affects the safe and economical operation of the transformer and the power supply quality, but also multiplies the line loss. If the equivalent resistance of a public power distribution line is R, and the maximum current flowing through it is IA = IB = IC = I, then the active power loss when the three-phase currents are balanced is ΔP = 3I²R. When the three-phase currents are unbalanced, there are negative-sequence and zero-sequence current components. Taking the positive-sequence current when balanced, i.e., I = IA = I1, as the standard, the active power loss at this time is: ε² = I²/I1, ε₀ = I₀/I₁, where ε₀ is the unbalance coefficient of the negative-sequence and zero-sequence currents. It can be seen from the formula that the greater the degree of three-phase current imbalance, the greater the active power loss. Therefore, it is necessary to regularly measure and adjust the three-phase load to strive for balance in the three-phase currents of the transformer and minimize line losses. 5. Application of Automatic Circuit Breakers for Distribution Transformers Under No-Load Conditions Applying automatic circuit breakers for distribution transformers under no-load conditions allows for the timely shutdown of agricultural distribution transformers that have been operating under no-load conditions for extended periods, significantly reducing line losses. For example, the no-load loss of a 10kV, 50kVA distribution transformer is 170W; shutting it down for one month can reduce power loss by 122.4 kWh. 6. Conclusion In summary, based on the operating characteristics of agricultural distribution transformers, energy-saving technologies such as selecting optimal transformer operating methods, choosing energy-efficient transformers, promoting the application of single-phase pole-mounted transformers, and appropriately controlling operating voltage can significantly reduce power losses in rural power grids.