Method and device for diagnosing signal status in measurement, drive, or control, and transformer used in the device

A device for diagnosing signal status, comprising:

• a transformer comprising a primary coil and a secondary coil,
• a signal generating means configured to generate an alternating voltage, the alternating voltage comprising a pulse voltage of an amplitude corresponding to an input voltage signal, connected to the primary coil of the transformer,
• a device-to-be-driven for performing measurement, drive, or control connected to the secondary coil of the transformer,
• a current measuring means for measuring change in the current of the primary coil caused by electric power consumed for an action of the device-to-be-driven, whereby diagnosis of signal status in the measurement, drive, or control by the device-to-be-driven is performed based on the measurement result of said change in current, and
• an intermediate tap provided to the primary coil and configured to be connected to the current measuring means,
• wherein
• the primary coil is divided into an anterior half and a posterior half, and the secondary coil is sandwiched by the anterior half and the posterior half of the primary coil, with the intermediate tap taken out from a center of the primary coil,
• the device-to-be-driven is a control actuator which is powered by a drive voltage corresponding to the voltage of the input voltage signal inputted to the signal generating means,
• the signal generating means is composed such that the drive voltage is generated in the secondary coil of the transformer receiving the alternating voltage signal, and
• an adding means configured to convert a primary side current generated by the current consumed depending on operating condition, normal or abnormal, of the actuator, or presence or absence of breaking of wire or short-circuit, into a feedback voltage which is fed back and added to the input voltage signal,
• whereby whether the actuator is operating normally or not and breaking of wire or short-circuit has occurred or not is diagnosed based on the feedback voltage by adding the converted voltage to the input voltage and the primary side current.