Transformer turns number testing circuit
Provided is a circuit capable of accurately testing the number of coil turns even with a transformer having a high turns ratio. A transformer turns number testing circuit is able to connect primary-side coils and secondary-side coils of a reference transformer and a to-be-tested transformer in phase and in series, and includes: a reference-side resistance element included in a reference-side loop circuit formed between both ends of the secondary-side coil of the reference transformer; a to-be-tested-side resistance element included in a to-be-tested-side loop circuit formed between both ends of the secondary-side coil of the to-be-tested transformer; and a voltage detector provided in a common line of the reference-side loop circuit and the to-be-tested-side loop circuit, the common line connecting a midpoint between the secondary-side coils of the reference transformer and the to-be-tested transformer and a midpoint between the reference-side resistance element and the to-be-tested-side resistance element.
1 . A transformer turns number testing circuit capable of testing the number of coil turns of a to-be-tested transformer based on a reference transformer,
the transformer turns number testing circuit being configured to be able to supply AC power to primary-side coils of the reference transformer and the to-be-tested transformer,
the transformer turns number testing circuit being configured to be able to connect the primary-side coils of the reference transformer and the to-be-tested transformer in phase and in series and connect secondary-side coils of the reference transformer and the to-be-tested transformer in phase and in series,
the transformer turns number testing circuit comprising:
a reference-side resistance element included in a reference-side loop circuit formed between both ends of the secondary-side coil of the reference transformer;
a to-be-tested-side resistance element included in a to-be-tested-side loop circuit formed between both ends of the secondary-side coil of the to-be-tested transformer; and
a voltage detector provided in a common line of the reference-side loop circuit and the to-be-tested-side loop circuit, the common line connecting a midpoint between the secondary-side coils of the reference transformer and the to-be-tested transformer and a midpoint between the reference-side resistance element and the to-be-tested-side resistance element,
wherein the to-be-tested-side resistance element has a resistance value equal to a resistance value of the reference-side resistance element, and
the voltage detector is a resistance element having a higher resistance value than the reference-side resistance element and the to-be-tested-side resistance element.
2 . The transformer turns number testing circuit according to claim 1 , further comprising:
a rectifier circuit configured to rectify an AC voltage detected by the voltage detector to convert the AC voltage into a DC voltage;
a comparator configured to compare the DC voltage converted by the rectifier circuit with a reference voltage; and
an output unit configured to output a testing result of the number of coil turns of the to-be-tested transformer based on an output of the comparator.
3 . A transformer turns number testing circuit capable of testing the number of coil turns of a to-be-tested transformer based on a reference transformer,
the transformer turns number testing circuit being configured to be able to supply AC power to primary-side coils of the reference transformer and the to-be-tested transformer,
the transformer turns number testing circuit being configured to be able to connect the primary-side coils of the reference transformer and the to-be-tested transformer in phase and in series and connect secondary-side coils of the reference transformer and the to-be-tested transformer in phase and in series,
the transformer turns number testing circuit comprising:
a reference-side resistance element included in a reference-side loop circuit formed between both ends of the secondary-side coil of the reference transformer;
a to-be-tested-side resistance element included in a to-be-tested-side loop circuit formed between both ends of the secondary-side coil of the to-be-tested transformer; and
a voltage detector provided in a common line of the reference-side loop circuit and the to-be-tested-side loop circuit, the common line connecting a midpoint between the secondary-side coils of the reference transformer and the to-be-tested transformer and a midpoint between the reference-side resistance element and the to-be-tested-side resistance element,
wherein each of the reference transformer and the to-be-tested transformer includes a plurality of secondary-side coils,
the transformer turns number testing circuit is configured to be able to connect each pair of one secondary-side coil of the reference transformer and one secondary-side coil of the to-be-tested transformer in phase and in series, to be able to form reference-side loop circuits, each between both ends of each of the plurality of secondary-side coil of the reference transformer, and to be able to form to-be-tested-side loop circuits, each between both ends of each of the plurality of secondary-side coil of the to-be-tested transformer,
the reference-side resistance element is provided in each of the reference-side loop circuits,
the to-be-tested-side resistance element is provided in each of the to-be-tested-side loop circuits, and
the voltage detector is provided in each of common lines of the reference-side loop circuits and the to-be-tested-side loop circuits, the common lines each connecting a midpoint between the secondary-side coils of the reference transformer and the to-be-tested transformer connected in phase and in series and a midpoint between the reference-side resistance element provided in the reference-side loop circuit and the to-be-tested-side resistance element provided in the to-be-tested-side loop circuit.
4 . The transformer turns number testing circuit according to claim 3 ,
wherein the to-be-tested-side resistance element has a resistance value equal to a resistance value of the reference-side resistance element, and
the voltage detector is a resistance element having a higher resistance value than the reference-side resistance element and the to-be-tested-side resistance element.
5 . The transformer turns number testing circuit according to claim 3 , further comprising:
a rectifier circuit configured to rectify an AC voltage detected by the voltage detector to convert the AC voltage into a DC voltage;
a comparator configured to compare the DC voltage converted by the rectifier circuit with a reference voltage; and
an output unit configured to output a testing result of the number of coil turns of the to-be-tested transformer based on an output of the comparator.