Method and a control unit for starting a compressor

Abstract

A method and a control unit for starting a compressor (3) in a refrigeration system (1) further comprising a condenser (2) and an evaporator (4). If an attempt to start-up the compressor (3) is unsuccessful a condenser cooling means, e.g. a fan, is started in order to provide cooling for the condenser (2). Thereby, if the temperature of the condenser is sufficiently high to cause an increased pressure on the condenser side of the compressor (3), cooling is provided for the condenser (2) in order to ensure a reliable start-up of the compressor (3). On the other hand, if the temperature of the condenser (2) is sufficiently low to ensure a reliable start-up of the compressor (3), cooling is not provided, thereby saving power while ensuring reliable start-up of the compressor (3).

Description

CROSS REFERENCE TO RELATED APPLICATIONS: [0001] Applicant hereby claims foreign priority benefits under U.S.C. §119 from Danish Patent Application No. PA 2006 00052 filed on Jan. 12, 2006, the contents of which are incorporated by reference herein. FIELD OF THE INVENTION [0002] The present invention relates to a method for starting a compressor in a refrigeration system in a manner which conserves power while ensuring reliable start-up of the compressor. Furthermore, the present invention relates to a control unit for controlling the start-up of a compressor and a starter assembly comprising such a control unit. BACKGROUND OF THE INVENTION [0003] In some refrigeration applications the refrigeration system will be subject to relatively large variations in the ambient temperature, resulting in relatively large temperature variations of the various parts of the refrigeration system. This is in particular the case in automotive applications, such as refrigeration systems positioned in v...

AI Technical Summary

Benefits of technology

"The invention provides a method for starting a compressor in a refrigeration system in a reliable and energy-conserving manner. The method involves determining whether the compressor has successfully started up, and if not, starting a condenser cooling means and repeating the process until a successful start-up is achieved. This method can be used in automotive applications and other refrigeration systems to ensure reliable start-up of the compressor while conserving energy."

Problems solved by technology

In some refrigeration applications the refrigeration system will be subject to relatively large variations in the ambient temperature, resulting in relatively large temperature variations of the various parts of the refrigeration system.

Increasing temperatures of the parts of the refrigeration system will lead to increasing pressure of the refrigerant.

This increase in temperature, in particular when it occurs on the condenser side of the compressor, has the consequence that it is difficult to restart the compressor following a period in time where the compressor has been stopped.

A disadvantage of the methods described in U.S. Pat. No. 4,941,325 and U.S. Pat. No. 6,155,062 is that the condenser fan is started in order to provide cooling for the condenser each time an attempt to start the compressor is initiated.

Thereby reliable start-up of the compressor is obtained, but at the expense of a higher power consumption.

This is particularly disadvantageous in situations where the available power is limited, e.g. when the compressor is powered by a battery.

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