Distributed-constant type transformer for voltage conversion

Patent metadata

Field	Value
Publication number	US-9712069-B2
Application number	US-201414906517-A
Country	US
Kind code	B2
Filing date	Aug 5, 2014
Priority date	Aug 29, 2013
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A transformer of distributed-constant type is provided between an AC power supply with a frequency f and a load with a resistance value R, and includes: a first converter connected to the AC power supply and having a length of λ/4; and a second converter provided between an end of the first converter and the load, and having a length of λ/4, where a wavelength at the frequency f is λ. Such a transformer has a small size and a light weight, and does not need a coil, an iron core, and the like as used in a conventional transformer.

First claim

The invention claimed is:

1. A distributed-constant type transformer, for voltage conversion, provided between an AC power supply with a frequency f and a load with a resistance value R, the transformer comprising:
a first converter connected to the AC power supply and forming a first distributed-constant circuit that has a length of λ/4 from an input end thereof to an output end thereof and a characteristic impedance Z C1 , λ being a wavelength at the frequency f; and
a second converter provided between the output end of the first converter and the load, the second converter forming a second distributed-constant circuit that has a length of λ/4 from an input end thereof to an output end thereof and a characteristic impedance Z C2 ,
wherein
an input impedance Z in as seen from the input end of the first converter is defined by a relation:
Z in =( Z C1 2 /Z C2 2 ) R.

2. A transformer comprising:
a circuit configured to perform switching; and
the transformer according to claim 1 , interposed in the circuit.

3. The transformer according to claim 1 , wherein the first converter and the second converter are each formed by a cable.

4. The transformer according to claim 3 , wherein the cable is integrated with a power cable of a distribution line.

5. The transformer according to claim 4 , wherein the frequency of the AC power supply is at least 1 MHz.

6. The transformer according to claim 3 , wherein the frequency of the AC power supply is at least 1 MHz.

Assignees

• Sumitomo Electric Industries
• Nat Univ Corp Toyohashi Univ Of Tech

Inventors

• Nakahata Hideaki
• Shiga Nobuo
• Hirotsu Kenichi
• Ohira Takashi
• Yamada Kyohei

Classifications

• H02M5/10 Primary

  using transformers · CPC title

• H02M5/293 Primary

  using semiconductor devices only · CPC title