Cooling device, in particular for cooling components housed in a switchgear cabinet, corresponding use and corresponding method

Abstract

The disclosure relates to a cooling device, in particular for cooling components that are housed in a switchgear cabinet, comprising a first cooling fan for blowing air from the switchgear cabinet through a first heat exchanger, and a second cooling fan for blowing ambient air through a second heat exchanger, characterized in that the cooling device further comprises a voltage supply having a step-up and/or step-down converter, which is connected via a rectifier to a wide-range input for single-phase or multiphase AC voltage, and which charges a capacitor to a DC link voltage which is higher or lower than a mains voltage across the wide-range input, a power supply unit of at least one of the two cooling fans being connected in parallel to the capacitor. The disclosure further relates to the use of such a cooling device and to a corresponding method for operating the cooling device.

Claims

1. A cooling device, in particular for cooling components that are housed in a switchgear cabinet, comprising a first cooling fan for blowing air from the switchgear cabinet through a first heat exchanger, and a second cooling fan for blowing ambient air through a second heat exchanger, the cooling device further comprising a compressor-driven cooling circuit having a compressor and a mechanical or electronic choking element, characterized in that the cooling device comprises a voltage supply having a step-up and/or a step-down converter, which is connected via a rectifier to a wide-range input for single-phase or multiphase AC voltage, and which charges a capacitor to a DC link voltage which is higher or lower than a mains voltage across the wide-range input, the capacitor being connected in parallel to a three-phase inverter which supplies three-phase current to the compressor, and a power supply unit of at least one of the two cooling fans being connected in parallel to the capacitor, so that, irrespective of a single-phase or multiphase input AC voltage across the wide-range input, the compressor can be operated on the nominal three-phase voltage that is necessary for a required compressor output level.

2. The cooling device according to claim 1, wherein for condensate management, the voltage supply has a heating element terminal for connecting an electric heating element that is controlled by a controller, said terminal being connected in parallel to the capacitor.

3. The cooling device according to claim 1, wherein a mains filter is connected to at least one outer conductor, one grounding conductor and, if present, one neutral conductor of the wide-range input, the grounding conductor leading from the wide-range input through the mains filter and from there directly to a three-phase outlet, to which the three-phase current for the compressor is supplied.

4. The cooling device according to claim 1, wherein the three-phase inverter is controlled by an inverter controller such that the three-phase current is supplied by the three-phase inverter at the three-phase power required to achieve a given compressor output level.

5. The cooling device according to claim 1, wherein the step-up and/or step-down converter is controlled via a converter controller such that the capacitor is charged via the step-up and/or step-down converter to a DC link voltage, the dimensions of which are such that the power supply voltage required to operate the first and/or second cooling fan is supplied via the power supply unit.

6. The cooling device according to claim 1, wherein the wide-range input for single-phase or three-phase AC voltage is designed at least for input voltages of between 110 V and 240 V and/or between 380 and 460V.

7. The cooling device according to claim 1, wherein the compressor and/or the cooling fans have brushless direct current motors.

8. The use of a cooling device according to claim 1 for operating the compressor on the nominal three-phase voltage necessary for a required compressor output level, irrespective of a single-phase or multiphase input AC voltage across the wide-range input, wherein for varying the output level of the compressor, the three-phase inverter is designed to raise or lower a nominal three-phase voltage based on the compressor output level that is required.

9. The method for operating a cooling device according to claim 1, comprising the following steps: rectifying and raising and/or lowering a single-phase or multiphase input AC voltage between 110 V and 460 V to a constant DC link voltage; supplying the DC link voltage to a power supply unit (6) of the cooling fan or cooling fans, the dimensions of the DC link voltage being such that the power supply unit is able to supply the power supply voltage required to operate the first and/or second cooling fan; feeding the DC link voltage to the three-phase inverter; determining the required compressor output level; adjusting the compressor-based nominal three-phase voltage that has been converted by the three-phase inverter until the required compressor output level is achieved.

Description

DRAWINGS

(1) The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

(2) Details of the disclosure will be explained below with reference to the preferred embodiment depicted in the following FIGURE in the form of a block diagram.

DETAILED DESCRIPTION

(3) Example embodiments will now be described more fully with reference to the accompanying drawings.

(4) For purposes of simplification, the FIGURE shows only a block diagram of the voltage supply 1 for the cooling device according to the disclosure. Voltage supply 1 has a wide-range input 4 for an up to three-phase AC voltage or a DC voltage. A grounding conductor terminal may also be provided. To increase interference immunity and decrease interference output, wide-range input 4 is connected to a mains filter 8. Mains filter 8 has a three-phase output, which is connected to an input of a rectifier 3 designed as a rectifier bridge. Rectifier 3 generates a DC voltage which is fed to the step-up and/or step-down converter 2. From the DC voltage that is supplied via rectifier 3, step-up and/or step-down converter 2 generates a constant DC link voltage of 380 V, for example, which is higher or lower than the voltage supplied by the rectifier depending on the output voltage, and charges a capacitor 5 with said DC link voltage. The DC link voltage is fed to a power supply unit for the cooling fans 20, 30, which is connected in parallel to capacitor 5. Step-up and/or step-down converter 2 is preferably a combined step-up and step-down converter.

(5) Step-up and/or step-down converter 2 is controlled by a converter controller 11, with controller 11 being designed to control step-up and/or step-down converter 2 so as to charge capacitor 5 with a constant electrical voltage, irrespective of the voltage across the wide-range input 4.

(6) The DC link voltage is fed to a three-phase inverter 7, which is controlled by an inverter controller 10. Inverter controller 10 is designed to control three-phase inverter 7 such that three-phase inverter 7 supplies the three-phase current at the three-phase power necessary to achieve a given compressor output level. The three-phase current generated by three-phase inverter 7 is supplied to compressor 9 via a three-phase output.

(7) For condensate management, voltage supply 1 may further comprise a terminal 12 for a heating element, with the capacitor voltage of 380 V, for example, being applied across terminal 12. The heating element can be controlled via a controller (not shown) for as-needed operation.

(8) The features of the disclosure disclosed in the foregoing description, in the drawings and in the claims may be considered essential both individually and in any combination to the implementation of the disclosure.

(9) The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.