POWER SUPPLY WITH A SWITCH CONVERTER

• US 20160154418A1
• Filed: 11/23/2015
• Published: 06/02/2016
• Est. Priority Date: 11/28/2014
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: PORTISCH, Daniel, AUGESKY, Christian
• Granted Patent: US 9,606,565 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 31/40 Testing power supplies testing photovoltaic devices H02S50/10
• CPC Class Codes: G05F 3/26 Current mirrors
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators

Abstract

A power supply has a switch converter, a circuit breaker, a storage inductor and a peak current controller, wherein a first shunt resistor is arranged in a positive cable, a first operational amplifier is connected the first shunt resistor to detect a voltage drop across the first shunt resistor, an auxiliary measuring signal at the output of the first operational amplifier is reflected via a current mirror to ground, a second operational amplifier is connected to the second shunt resistor for impedance amplification such that a DC measuring signal is present at the output of the second operational amplifier, an RC element having a resistor and capacitor is connected to an inductor, the RC element being configured such that an AC measuring signal at the output of the RC element reproduces a current through the storage inductor, and where the AC measuring signal is added to the DC measuring signal.

Claims

1. A power supply including a switch converter, and which is connectable to an input-side voltage by a positive cable and to a ground potential by a negative cable, the power supply comprising:

a circuit breaker;

a storage inductor;

a peak current controller;

a first operational amplifier;

a first shunt resistor arranged in the positive cable and connected to the first operational amplifier to detect a voltage drop across the first shunt resistor;

a second shut resistor;

a current mirror which reflects an auxiliary measuring signal at the output of the first operational amplifier via the second shunt resistor onto the ground potential;

a second operational amplifier connected to the second shunt resistor to provide impedance amplification such that a DC measuring signal is present at an output of the second operational amplifier; and

an RC element comprising a resistor and capacitor, the RC element being connected to the storage inductor and configured such that an AC measuring signal at an output of the RC element reproduces a current through the storage inductor, the AC measuring signal being added to the DC measuring signal.

2. The power supply as claimed in claim 1, wherein an input-side connection of the storage inductor is connected to a first connection of the resistor of the RC element;

wherein an output-side connection of the storage inductor is connected to a first connection of the capacitor of the RC element; and

wherein a second connection of the resistor and a second connection of the capacitor are connected at the output of the RC element.

3. The power supply as claimed in claim 1, wherein the output of the RC element is connected to the output of the second operational amplifier via a high-pass filter.

4. The power supply as claimed in claim 2, wherein the output of the RC element is connected to the output of the second operational amplifier via a high-pass filter.

5. The power supply as claimed in claim 3, wherein the output of the RC element is connected to a measurement output via a filter capacitor;

and

wherein the output of the second operational amplifier is connected to the measurement output via a filter resistor.

6. The power supply as claimed in claim 1, further comprising:

a snubber resistor arranged between the positive cable and a negative input of the first operational amplifier.

7. The power supply as claimed in claim 1, further comprising:

a smoothing capacitor is arranged between the output of the first operational amplifier and a negative input of the first operational amplifier.

8. The power supply as claimed in claim 1, wherein the current mirror comprises a first PNP transistor and a second PNP transistor;

wherein the first PNP transistor is coupled as a diode,

wherein an emitter electrode of the first PNP transistor and an emitter electrode of the second PNP transistor are each connected to the output of the first operational amplifier via a first series resistor and a second series resistor;

wherein a collector electrode of the first PNP transistor is connected to a negative input of the first operational amplifier, and

wherein a collector electrode of the second PNP transistor is connected to the ground potential via the second shunt resistor.

9. The power supply as claimed in claim 1, wherein the second operational amplifier is formed as an inverting amplifier via two snubber resistors.

10. The power supply as claimed in claim 1, wherein one of (i) the DC measuring signal or (ii) the DC measuring signal with the added AC measuring signal is supplied to a current control circuit which regulates an output current of the switch converter to a target value.

11. The power supply as claimed in claim 1, wherein at least one further switch converter is arranged in the power supply and that all switch converters have a shared negative cable.

12. The power supply as claimed in claim 11, wherein outputs of two switch converters are connected in parallel.

13. The power supply as claimed in claim 11, wherein all switch converters are of the same construction.

14. The power supply as claimed in claim 12, wherein all switch converters have the same construction.