# US 12,771,264 B2 · Inverter circuit and electric field coupling non-contact power feeding device

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,771,264 B2
- Document ID: US12771264B2
- Status: Granted
- Kind: B2
- Application number: 18/285,470
- Filed: 2022-01-26
- Published: 2025-10-02
- Granted: 2026-10-20
- Earliest claimed: 2021-06-21
- Assignees: Sumida Corporation
- Applicants: Sumida Corporation
- Inventors: Hiroyuki Miyazaki
- Web page: https://patentgrep.com/patent/US12771264B2

## CPC

- H02M 7/53832: {in a push-pull arrangement}
- H02M 7/4815: {Resonant converters (H02M7/4811 and H02M7/4826 take precedence)}
- H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P)

## Abstract

An inverter circuit includes a primary-side circuit having a plurality of self-excited oscillator circuits connected to a DC power supply and a secondary-side circuit for outputting multi-phase AC power in accordance with oscillation of the plurality of self-excited oscillator circuits. Each of the plurality of self-excited oscillator circuits includes a power transmission coil, a resonant capacitor, a pair of switching elements, a drive coil, and a phase-shift filter. A voltage is applied to each control electrode of the pair of switching elements from the drive coil of another self-excited oscillator circuit. The phase of the voltage applied to each control electrode of the pair of switching elements is shifted by a phase-shift amount corresponding to number of phases of the multi-phase AC power for each self-excited oscillator circuit according to at least an action of the phase-shift filter.

## Claims

### Claim 1

An inverter circuit comprising:
a primary-side circuit including a plurality of self-excited oscillator circuits connected to a DC power supply; and
a secondary-side circuit configured to output multi-phase AC power having phases different from each other according to oscillation of the plurality of self-excited oscillator circuits, wherein
each of the plurality of self-excited oscillator circuits includes:
a power transmission coil;
a resonant capacitor constituting a resonant circuit together with the power transmission coil;
a pair of switching elements connected to the power transmission coil;
a drive coil configured to generate an induced electromotive force having a frequency corresponding to a resonance frequency of the resonant circuit, wherein the drive coil of a first self-excited oscillation circuit of the plurality of self-excited oscillator circuits applies a first voltage to each control electrode of the pair of switching elements of another self-excited oscillator circuit of the plurality of self-excited oscillator circuits according to the induced electromotive force; and
a phase-shift filter,
the secondary-side circuit includes a plurality of power reception coils, each of the plurality of power reception coils is magnetically coupled to the power transmission coil of each of the plurality of self-excited oscillator circuits,
a second voltage is applied to each control electrode of the pair of switching elements of the first self-excited oscillation circuit from the drive coil of another self-excited oscillator circuit of the plurality of self-excited oscillator circuits, and
each of the first and second voltages is shifted by a phase-shift amount corresponding to a number of phases of the multi-phase AC power for a respective self-excited oscillator circuit of the plurality of self-excited oscillator circuits according to at least an action of the phase-shift filter.

### Claim 2 (depends on 1)

The inverter circuit according to claim 1, wherein
the drive coil of the first self-excited oscillation circuit is magnetically coupled to the power transmission coil of the first self-excited oscillator circuit, and
the phase-shift filter of the first self-excited oscillator circuit is provided between the drive coil of the first self-excited oscillator circuit and each control electrode of the pair of switching elements of another self-excited oscillator circuit of the plurality of self-excited oscillator circuits.

### Claim 3 (depends on 1)

The inverter circuit according to claim 1, wherein
the first self-excited oscillator circuit further includes a drive control coil connected in parallel to the power transmission coil or the resonant capacitor of the first self-excited oscillator circuit, or to the power reception coil magnetically coupled to the power transmission coil of the first self-excited oscillator circuit,
the drive coil of the first self-excited oscillator circuit is magnetically coupled to the drive control coil of the first self-excited oscillator circuit, and
the phase-shift filter of the first self-excited oscillator circuit is provided between the drive coil of the first self-excited oscillator circuit and each control electrode of the pair of switching elements of another self-excited oscillator circuit of the plurality of self-excited oscillator circuits.

### Claim 4 (depends on 1)

The inverter circuit according to claim 1, wherein
the first self-excited oscillator circuit further includes a drive control coil connected in parallel to the power transmission coil or the resonant capacitor of the first self-excited oscillator circuit, or to the power reception coil magnetically coupled to the power transmission coil of the first self-excited oscillator circuit,
the drive coil of the first self-excited oscillator circuit is magnetically coupled to the drive control coil of the first self-excited oscillator circuit, and
the phase-shift filter of the first self-excited oscillator circuit is connected to the drive control coil of the first self-excited oscillator circuit.

### Claim 5 (depends on 1)

An electric field coupling non-contact power feeding device including the inverter circuit according to claim 1.