#transformer  an electrical device by which alternating current of one voltage is changed to another voltage
  supertype:  electrical_device  a device that produces or is powered by electricity
  part:  induction_coil  primary_coil  secondary_coil
  subtype:  coil.transformer  a transformer that supplies high voltage to spark plugs in a gasoline engine
  subtype:  step-down_transformer  a transformer that reduces voltage
  subtype:  step-up_transformer  a transformer that increases voltage
     subtype:  cascade_transformer  a number of transformers in series; provides a high-voltage source
  subtype:  Tesla_coil  a step-up transformer with an air core; used to produce high voltages at high frequencies
  subtype:  voltage_regulator__voltageregulator  a transformer whose voltage ratio of transformation can be adjusted

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