Patent US5473528A successfully refreshed from Google Patents.
US5473528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Parallel connection of different types of AC power supplies of differing capacities
Assignee: Toshiba Corp
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Filing: 1994-12-28
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Granted: 1995-12-05
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Expires: 2014-12-28
Abstract
Abstract A power inverting method and system for connecting a plurality of AC power supplies to a common bus line in parallel wherein the AC power supplies are independently controlled so that power supplies with different rating characteristics can be coupled to the common bus line without adverse effects such as the existence of cross currents flowing between the different power supplies. In each AC power supply there is provided a system parameter calculating unit for calculating optimum load current, system impedance and output voltage parameters of the power supply which are then output to a reference data producing unit which generates appropriate feedback voltage and phase signals for output to a voltage controller and a phase synchronization controller, respectively. The voltage controller and phase synchronization controller output feedback signals to a power inverter which varies the power supply output. Using such feedback control in each of the plurality of power supply units enables a constant current to be output to a load on the system and eliminates the possibility of cross currents between the various power supply units.
Inventors
- 👤 Akio Hirata
- 👤 Yoshiaki Miyazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:47
CPC Classifications
H; H02; H02J; H02J3/00; H02J3/38; H02J3/40; H02J3/42; H02J9/00; H02J9/04; H02J9/06; H02J9/062; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/493; Y; Y02; Y02B; Y02B10/00; Y02B10/70
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
162 words
A power inverting method capable of parallel-connecting a plurality of power supply units to a common bus line, comprising the steps of: entering a plurality of input commands for changing a parameter of an AC (alternating current) output voltage of a power inverter employed in one power supply unit; detecting a variation in an AC output current of said one power supply unit when the AC output voltage of said power inverter is changed; processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total output power capable of being supplied from said common bus line to a load; and controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 2
Dependent Claim
162 words
A power inverting method capable of parallel-connecting a plurality of power supply units to a common bus line, comprising the steps of: entering a plurality of input commands for changing a parameter of an AC (alternating current) output voltage of a power inverter employed in one power supply unit; detecting a variation in an AC output current of said one power supply unit when the AC output voltage of said power inverter is changed; processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total output power capable of being supplied from said common bus line to a load; and controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 3
Dependent Claim
45 words
A power inverting method as claimed in claim 1, wherein said step of entering a plurality of input commands for changing said parameter of said AC voltage comprises entering said input commands under respectively different voltages for inferring said desirable parameter in said processing step.
Claim 4
Dependent Claim
155 words
A power inverting system comprising: a plurality of power supply units each having a power inverter and parallel-connected to a common bus line; means for detecting a variation contained in an AC output current of one power supply unit when a command for changing an amplitude of an AC output voltage of the power inverter of said one power supply unit is issued; means for processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total power output capable of being supplied from said common bus line to a load; and means for controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 5
Dependent Claim
155 words
A power inverting system comprising: a plurality of power supply units each having a power inverter and parallel-connected to a common bus line; means for detecting a variation contained in an AC output current of one power supply unit when a command for changing an amplitude of an AC output voltage of the power inverter of said one power supply unit is issued; means for processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total power output capable of being supplied from said common bus line to a load; and means for controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 6
Dependent Claim
56 words
A power inverting system as claimed in claim 3, further comprising: a battery coupled to an input side of said power inverter and capable of supplying DC power to said power inverter when an AC power supply by a main power source is interrupted, whereby said power inverting system functions as an uninterrupted power supply system.
Claim 7
Dependent Claim
16 words
A power inverting system as claimed in claim 4, wherein said battery is a rechargeable battery.
Claim 8
Dependent Claim
16 words
A power inverting system as claimed in claim 4, wherein said battery is a solar cell.
Claim 9
Dependent Claim
16 words
A power inverting system as claimed in claim 4, wherein said battery is a fuel battery.
Claim 10
Dependent Claim
31 words
A power inverting system as claimed in claim 3, wherein said detecting means is arranged by a current transformer for detecting said AC output current of said one power supply unit.
Claim 11
Dependent Claim
69 words
A power inverting system as claimed in claim 3, wherein said processing means includes: a system parameter calculating unit for calculating a parameter of said power inverting system by processing said variation contained in the AC output current to obtain system parameter inferred data; and a reference data producing unit for producing reference data containing voltage data, as said desirable parameter, in response to said system parameter inferred data.
Claim 12
Dependent Claim
70 words
A power inverting system as claimed in claim 9, wherein said controlling means includes at least: a voltage controller for controlling an amplitude of said AC output voltage of said power inverter in response to said voltage data of the reference data; and a phase controller for controlling a phase of said AC output voltage derived from the power inverter in response to said voltage data of the reference data.
Claim 13
Dependent Claim
63 words
A power inverting system as claimed in claim 10, wherein said controlling means further includes: an oscillator for oscillating a reference oscillating signal to be supplied to said phase controller functioning as a phase-locked loop circuit; and a pulse width modulation control circuit for controlling said power inverter in a pulse-width modulation mode under control of said voltage controller and said phase controller.
Claim 14
Dependent Claim
165 words
A power inverting method capable of parallel-connecting a plurality of power supply units to a common bus line, comprising the steps of: entering a plurality of input commands for changing an amplitude of an AC (alternating current) output voltage of a power inverter employed in one power supply unit; detecting a variation in an AC output current of said one power supply unit when the amplitude of said AC output voltage of said power inverter is changed; processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total output power capable of being supplied from said common bus line to a load; and controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 15
Dependent Claim
165 words
A power inverting method capable of parallel-connecting a plurality of power supply units to a common bus line, comprising the steps of: entering a plurality of input commands for changing an amplitude of an AC (alternating current) output voltage of a power inverter employed in one power supply unit; detecting a variation in an AC output current of said one power supply unit when the amplitude of said AC output voltage of said power inverter is changed; processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total output power capable of being supplied from said common bus line to a load; and controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 16
Dependent Claim
166 words
A power inverting method capable of parallel-connecting a plurality of power supply units to a common bus line, comprising the steps of: entering a plurality of input commands for changing a phase angle of an AC (alternating current) output voltage of a power inverter employed in one power supply unit; detecting a variation in an AC output current of said one power supply unit when the phase of said AC output voltage of said power inverter is changed; processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total output power capable of being supplied from said common bus line to a load; and controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
Claim 17
Dependent Claim
166 words
A power inverting method capable of parallel-connecting a plurality of power supply units to a common bus line, comprising the steps of: entering a plurality of input commands for changing a phase angle of an AC (alternating current) output voltage of a power inverter employed in one power supply unit; detecting a variation in an AC output current of said one power supply unit when the phase of said AC output voltage of said power inverter is changed; processing said variation in the AC output current to infer a desirable parameter required to share AC power which should be derived from said one power supply unit with respect to total output power capable of being supplied from said common bus line to a load; and controlling said one power supply unit to output a desirable voltage in response to said desirable parameter, whereby said power sharing operation for said one power supply unit is achieved independently of other power sharing operations for other power supply units.
References Cited (Backward Citations)
JPS5273326A
Cited
JPS5274825A
Cited
JPS5688676A
Cited
US4677535A
Cited
US4733341A
Cited
US5212630A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-12-04 | 1999-06-05 | 1999-12-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-12-04 | 2003-06-05 | 2003-12-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-12-04 | 2007-06-05 | 2007-12-05 | $7700.00 | Window Closed / Lapsed |