Distribution Network Hybrid Transformer for Load Current and Grid Voltage Compensation

Power quality has become a concern nowadays, due to the increasing and highly variable renewable energy systems connected to the distribution network and also due to the nonlinear loads that pollute the grid. A solution to this problem is the use of compensators to attenuate these disturbances. The use of a hybrid transformer composed by a conventional low-frequency transformer in conjunction with a power converter has become an interesting solution due to the high controllability and overall efficiency. In this paper, the model, control, and simulation of a hybrid transformer, where the converter is connected in series with the primary side and in parallel to the secondary side, is presented. Results show the correct operation of the converter in steady and transient state, successfully compensating grid voltage variations and load non-linear currents.