Method and circuit for the improved use of capacitance in an intermediate circuit

• US 10,411,614 B2
• Filed: 05/09/2014
• Issued: 09/10/2019
• Est. Priority Date: 05/17/2013
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Samsung SDI Company Limited
• Original Assignee: Robert Bosch GmbH
• Inventors: Butzmann, Stefan
• Primary Examiner(s): Fureman, Jared
• Assistant Examiner(s): Dominique, Emmanuel
• Application Number:
  US14/891,684
• Publication Number:
  US 20160099662A1
• Time in Patent Office: 1,950 Days
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: H02M 1/15 using active elements
• CPC Class Codes: H02M 5/2932 with automatic control of output voltage, current or power
• CPC Class Codes: H02M 5/297 for conversion of frequency
• CPC Class Codes: H02M 5/45 using semiconductor devices only
• CPC Class Codes: H02M 7/537 using semiconductor devices only, e.g. single switched pulse inverters
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

The disclosure relates to a method and a circuit for the improved use of a capacitance in an intermediate circuit. According to the disclosure, a change in a voltage in an intermediate circuit is detected and electrical energy is actively provided depending on the change in the electrical variable in order to compensate the change. According to the disclosure, a capacitance used in the intermediate circuit can end up significantly smaller if the electrical energy fed in is used, in that the voltage of the capacitance is supported by a current fed into the capacitance on the earth side.

Claims

1. A method for use of a capacitance in an intermediate circuit, the capacitance being connected in parallel with an inverter between a DC voltage connection and a ground connection, the method comprising:

charging the capacitance via an energy source connected to the DC voltage connection;

detecting a voltage dip in a voltage across the capacitance in the intermediate circuit; and

compensating for the voltage dip in the voltage by feeding electrical energy proportional to the voltage dip into a ground connection of the capacitance with a compensation unit, in response to detecting the voltage dip, the compensation unit having an energy buffer configured to store electric energy from the intermediate circuit and supply at least some of the electric energy that is fed into the ground connection.

2. The method as claimed in claim 1, wherein the voltage dip in the voltage is produced by a disturbance signal superimposed on the DC voltage connection, the disturbance signal comprising a periodic alternating signal caused by the inverter.

3. The method as claimed in claim 1, wherein the electrical energy fed into the capacitance is supplied via at least one of a switching circuit of the compensation unit and an analog amplification circuit of the compensation unit.

4. The method as claimed in claim 1, wherein the detecting of the voltage dip in the voltage comprises detecting the voltage dip in the voltage with high-pass filtering.

5. The method as claimed in claim 1, wherein the detecting of the voltage dip in the voltage comprises processing an electric variable using a microcontroller.

6. A circuit for use of a capacitance in an intermediate circuit of an on-board automobile energy system, the capacitance being connected in parallel with an inverter between a DC voltage connection and a ground connection, the capacitance being charged via an energy source connected to the DC voltage connection, comprising:

a detection unit configured to detect a voltage dip in a voltage across the capacitance in the intermediate circuit; and

a compensation unit configured to compensate for the voltage dip in the voltage by feeding electric energy proportional to the voltage dip into the ground connection in response to detecting the voltage dip, the compensation unit having an energy buffer configured to store electric energy from the intermediate circuit and supply at least some of the electric energy that is fed into the ground connection.

7. The circuit as claimed in claim 6, wherein

the detection unit comprises at least one of a high-pass filter and a microcontroller.

8. The circuit as claimed in claim 6, wherein

the compensation unit comprises at least one of a digital amplifier and an analog amplifier.

9. The circuit as claimed in claim 6, wherein

the compensation unit comprises a DC/DC converter configured to feed the electric energy into the ground connection.

10. The circuit as claimed in claim 6, wherein the energy buffer comprises a storage capacitor and an inductance.