The first pilot of the smart transformer installed in our Ormazabal Transformer Division

The first pilot of the smart transformer was installed in our Ormazabal Transformer Division (January 2017), one of the industrial facilities of Ormazabal (Loeches, Madrid), to keep the voltage stable and to assess Conservation Voltage Reduction (CVR) strategy taking into account the reactive compensation and PV generation. CVR aims to achieve a significant reduction of peak demand at no cost, by means of load shedding.

Transforma.smart and CVR strategy   Characteristics: 15 / 0.42 kV, 630 kVA; 9taps ±4% 1% step voltaje Reactive Power Compensator: 175mVar SPV plant: 263,34 kW

Test results show a clear dependence between voltage and power values: active and reactive.

As an illustration, we show two figures, where it can be observed that by decreasing the voltage we can reduce the power consumed.

Ormazabal challenge and solution:

CVR enables the reduction of peak demand and contributes to energy saving by decreasing the voltage magnitudes down to the minimum allowable limits without affecting the performance of the end devices.         The reduction in energy demand is dependent on the types of loads connected. CVR is more effective with constant impedance or constant current loads, where a reduction in voltage leads to a reduction in power. In addition, losses could be reduced for constant impedance loads due to reduced current. Factory test results confirmed the existence of relation between voltage changes and active/reactive power reduction.

Key Benefits to client:

• In the majority of cases (more than 50% of values), an application of the CVR strategy by means of two tap changes (each 1%) of transforma.smart presents saving of more than 1,5% of power.
• It was observed that each tap change allows to implicity describe load type downstream.