Phase controlled rectifier circuit for rapidly charging batteries

• US 4,253,054 A
• Filed: 02/05/1979
• Issued: 02/24/1981
• Est. Priority Date: 02/05/1979
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Steigerwald, Robert L.
• Primary Examiner(s): Hickey, Robert J.
• Application Number:
  US06/009,305
• Time in Patent Office: 750 Days
• Field of Search: 320/14, 320/21, 320/57, 320/59, 363/128
• US Class Current: 320/129
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: H02J 7/00711 with introduction of pulses during the charging process
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: Y02B 40/00 Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers
• CPC Class Codes: Y10S 320/24 Inductor

Abstract

An improved battery charger circuit for rapidly charing a battery by increasing the rate of battery charge acceptance through periodic battery discharge during the charging process includes a pair of first and second controlled rectifier circuits coupled to an AC source and adapted for coupling to a battery. The first controlled rectifier circuit is rendered conductive during the charging intervals to supply the battery with charge current from the AC source. The second controlled rectifier circuit is rendered conductive during battery discharge intervals to discharge the battery in a substantially lossless manner by conducting battery discharge current through the AC source, thus realizing a highly efficient battery charger.

Claims

1. An efficient battery charger for rapidly charging batteries by increasing the rate of battery charge acceptance through periodic battery discharge in a subsantially lossless manner at a high rate for short intervals during the charging process comprising:

(a) an AC source;

(b) a first full bridge controlled rectifier circuit coupled to said AC source for providing charge current to a battery at predetermined intervals;

(c) a second full bridge controlled rectifier circuit coupled to said first full bridge controlled rectifier circuit and adapted for coupling to said battery, said second full bridge controlled rectifier circuit discharging said battery by conducting battery discharge current to said AC source during other than said predetermined intervals; and

(d) filter means coupled to said first and second full bridge controlled rectifier circuits for smoothing current through said battery.

2. The invention according to claim 1 wherein said AC source comprises a three phase AC source and wherein said first full bridge controlled rectifier circuit is configured of a three phase full bridge controlled rectifier network, said three phase full bridge controlled rectifier network comprising:

(a) three pairs of thyristors, the thyristors in each said thyristor pair being coupled in series aiding fashion, the junction between thyristors of each thyristor pair being coupled to a respective phase of said three phase AC source, said thyristor pairs being coupled in parallel and adapted for coupling to said filter means, said thyristors being sequentially rendered conductive in a predetermined order to supply charge current to said batter at predetermined intervals.

3. The invention according to claim 2 wherein said filter means comprises an inductor coupled between said first full bridge controlled rectifier circuit and said battery.

4. The invention according to claim 2 wherein said second full bridge controlled rectifier circuit is configured of a three phase full bridge bridge controlled rectifier network and comprises:

(a) a second three pairs of thyristors, the thyristors in each of said second three pairs being coupled in series aiding fashion, the junction between thyristors of each of said second three pairs being coupled to a corresponding phase of said three phase AC source, said second three pairs of thyristors being coupled in parallel and adapted for coupling to said filter means, said thyristors being sequentially rendered conductive in a predetermind order for conducting battery discharge current to said three phase AC source at other than said predetermind intervals.

5. The invention according to claim 4 including gating means for supply gating signals to each thyristor of said first three pairs of thyristors and said second three pairs of thyristors for rendering the thyristors of said first three pairs of thyristors conductive during said predetermined intervals and for rendering the thyristors of said second three pairs of thyristors conductive during other than said predetermined intervals.

6. The invention according to claim 2 wherein said second full bridge controlled rectifier circuit is configured of a full wave bridge rectifier network and comprises:

(a) a fourth thyristor pair comprised of a first and second thyristor coupled in series aiding fashion and adapted for coupling at the junction between thyristors to the positive terminal of a battery under charge;

(b) a fifth thyristor pair comprised of a third and fourth thyristor coupled in series aiding fashion and adapted for coupling at the junction between thyristors to the negative terminal of a battery under charge, said fourth and fifth thyristor pairs being coupled through said filter means to said first full bridge controlled rectifier circuit; and

(c) first and second thyristor commutating circuits coupled across said second and third thyristors, respectively,

(d) said first and fourth thyristors being rendered conductive at said predetermined intervals to conduct charge current to said battery from said first controlled rectifier circuit and said second and third thyristors being rendered conductive at other than said predetermined intervals to discharge said battery by conducting battery discharge current to said AC source.

7. The invention according to claim 6 including gating means for supplying gating signals to each thyristor of said first three pairs of thyristors and said fourth and said fifth pairs of thyristors for rendering the thyristors of said first three pairs of thyristors and the first and third thyristors of said fourth and fifth thyristor pairs conductive during said predetermined intervals and for rendering the thyristors of said three pairs of thyristors and the second and fourth thyristors of said third and fourth thyristor pairs conductive during other than said predetermined intervals.

8. An efficient battery charger for rapidly charging batteries by increasing the rate of battery charge acceptance through periodic battery discharge in a substantially lossless manner at a high rate for short intervals during the charging process comprising:

(a) an AC source;

(b) a battery to be charged;

(c) a first phase controlled full bridge rectifier network coupled to said AC source for supplying DC charge current to said battery at predetermined intervals;

(d) a second phase controlled full bridge rectifier network coupled in parallel with said first phase controlled full bridge rectifier network for discharging said battery at other than said predetermined-intervals by providing a low loss discharge path to conduct said battery discharge current through said AC source; and

(e) inductor means for coupling said battery to said first and second phase controlled full bridge rectifier networks.

9. An efficient battery charger for rapidly charging batteries by increasing the rate of battery charge acceptance through periodic battery discharge in a substantially lossless manner at a high rate for short intervals during the charging process comprising:

(a) an AC source;

(b) a battery under charge;

(c) a phase controlled rectifier network coupled to said AC source for supplying DC charge current to said battery during predetermined intervals and for conducting battery discharge current to said AC source during other than said predetermined intervals;

(d) a controlled rectifier network for conducting charge current from said first phase controlled rectifier network to said battery during said predetermined intervals and for discharging said battery by conducting battery discharge current to said first phase controlled rectifier network for conduction through said AC source during other than said predetermined intervals; and

(e) inductor means for coupling said first and second phase controlled rectifier networks.