EP0435460A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Current sharing control for paralleled power converters
Assignee: AT&T Inc
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Filing: 1990-11-27
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Granted: —
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Expires: 2010-11-27
Abstract
Abstract Current sharing between paralleled power converters (110,210) is attained by adjusting the error signal in the converters' regulation circuits to assure that all the paralleled converters have a regulated output voltage that forces the converters to share the load equally. In particular circuitry (140) is provided to limit the variation in output voltage that can be achieved through operation of the current sharing control.
Inventors
- 👤 Thomas Patrick Loftus
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 13:35
CPC Classifications
H; H02; H02J; H02J3/00; H02J3/38; H02J3/46; H02J1/00; H02J1/10; H02J1/102; H02J1/108
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
182 words
A power converter adapted for current sharing with like power converters when connected to it in parallel, comprising a power switch (115) for periodically interconnecting energy from an input to an output, and CHARACTERISED BY circuitry (130-161) for generating a power switch control signal for regulating the energy transfer from the input to the output, comprising current sensing circuitry (130,132,133,134,136,137) for sensing a power current signal of the power converter in an energy transfer from the input to the output, and for balancing the power current signal with an external power current signal from the like power converters when connected to it in parallel to generate a balanced current sense signal, and circuitry (140,150) for applying the balanced current sense signal to an error amplifier (161) to compare it with a reference signal (105), the applying circuitry comprising a diode transistor current amplifier (140) comprising an input diode device (146) and an output transistor device (151) operative for transforming small balanced current sense signals into an error signal and limiting large balanced current sense signals to limit voltage excursions at the output.
Claim 2
Dependent Claim
121 words
A converter as claimed in claim 1, wherein the current sensing circuitry comprises a current transformer (130) having a current sensing primary winding (129) in series with the power switch (115) and a secondary winding (131) connected to a rectifying diode (132), a storage capacitor (133) for storing a voltage proportional to the power current signal, and a discharge resistor (134) connected in shunt with the storage capacitor, the storage capacitor having a first plate connected to the rectifying diode (132) and to a circuit node (135) which is for connection to a second storage capacitor (233) connected for storing a voltage proportional to a power current of a second power converter, and a second plate connected to the applying circuitry.
Claim 3
Dependent Claim
42 words
A converter as claimed in claim 1 or 2 wherein a first voltage divider (150) is connected at an input to the error amplifier (161), and the output transistor device (151) is connected to vary a division ratio of the voltage divider.
References Cited (Backward Citations)
No citation records indexed.
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