Power supply system

Patent metadata

Field	Value
Publication number	US-10075096-B2
Application number	US-201715564519-A
Country	US
Kind code	B2
Filing date	Mar 29, 2017
Priority date	May 24, 2016
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

A pseudo-resonant element ( 130 ) is disposed in series with respect to an inductive load ( 180 ) on the inductive load ( 180 ) side rather than an output end of an inverter unit ( 120 ) constituted of a magnetic energy recovery switch.

First claim

The invention claimed is:

1. A power supply system comprising: a magnetic energy recovery switch; a frequency setting device; a control device; and a pseudo-resonant element, converting direct-current power into alternating-current power, and supplying the alternating-current power to an inductive load,
wherein the magnetic energy recovery switch comprises: one or a plurality of first capacitors; and a plurality of switches,
wherein the frequency setting device sets an output frequency of the magnetic energy recovery switch,
wherein the control device controls an on and off operation of the plurality of switches based on an output frequency set by the frequency setting device,
wherein the magnetic energy recovery switch recoveries magnetic energy stored in the inductive load and stores the magnetic energy as electrostatic energy in the first capacitor, and supplies the stored electrostatic energy to the inductive load, by on and off of the plurality of switches,
wherein the pseudo-resonant element is constituted of at least one passive element including a second capacitor,
wherein the first capacitor is disposed in series with respect to the inductive load,
wherein the second capacitor is connected in series with respect to the inductive load on the inductive load side rather than an output end of the magnetic energy recovery switch,
wherein a value of an inductive reactance on the inductive load side rather than an output end of the magnetic energy recovery switch exceeds a value of a capacitive reactance on the inductive load side rather than an output end of the magnetic energy recovery switch, and
wherein the plurality of switches switch on and off when a voltage of both ends of the first capacitor is “0” (zero).

2. The power supply system according to claim 1 , wherein a value of a synthetic reactance of an inductive reactance of the pseudo-resonant element and an inductive reactance of the inductive load exceeds a value of a capacitive reactance of the pseudo-resonant element.

3. The power supply system according to claim 1 , wherein a value of an electrostatic capacitance of the second capacitor is a value exceeding a reciprocal of a value obtained by multiplying a synthetic inductance of an inductance of the pseudo-resonant element and an inductance of the inductive load, and a square of an angular frequency when a frequency for on and off of the switch is the output frequency.

4. The power supply system according to claim 1 ,
wherein the output frequency is equal to or less than a resonance frequency, and
wherein the resonance frequency is a resonance frequency in a resonant circuit including the first capacitor, the pseudo-resonant element, and the inductive load.

5. The power supply system according to claim 1 , wherein when an electrostatic capacitance of the first capacitor is set as C m [F], a synthetic inductance of an inductance of the pseudo-resonant element and an inductance of the inductive load is set as L [H], an electrostatic capacitance of the second capacitor is set as C r [F], and an angular frequency when a frequency for on and off of the switch is the output frequency is set as ω [rad/s], a following (A) expression is established:

C

m
⁢

≦

1

ω
2

⁡

(

L
-

1

ω
2

⁢

C
r

)

.

(
A
)

6. The power supply system according to claim 1 , further comprising:
a transformer disposed between an output end of the magnetic energy recovery switch, and the pseudo-resonant element and the inductive load,
wherein when an electrostatic capacitance of the first capacitor is set as C m [F], a synthetic inductance of an inductance of the pseudo-resonant element and an inductance of the inductive load is set as L [H], an electrostatic capacitance of the second capacitor is set as C r [F], an angular frequency when a frequency for on and off of the switch is the output frequency is set as ω [rad/s], and a turns ratio which is a value obtained by dividing a number of turns of a primary winding of the transformer by a number of turns of a secondary winding of the transformer is set as n, a following (B) expression is established:

C
m

≦

1

n
2

⁢

ω
2

⁡

(

L
-

1

ω
2

⁢

C
r

)

.

(
B
)

7. The power supply system according to claim 1 ,
wherein the pseudo-resonant element is constituted of a second capacitor, and
wherein an inductive reactance and an inductance of the pseudo-resonant element

Assignees

• Nippon Steel & Sumitomo Metal Corp

Inventors

• Fukutani Kazuhiko

Classifications

• H02J7/345

  using capacitors as storage or buffering devices · CPC title

• H02M1/08

  Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters · CPC title

• H05B6/04

  Sources of current · CPC title

• H05B6/06

  Control, e.g. of temperature, of power · CPC title

• H02M7/4826 Primary

  operating from a resonant DC source, i.e. the DC input voltage varies periodically, e.g. resonant DC-link inverters · CPC title