Compressor unit and method for operating a compressor unit

Abstract

A compressor unit including a screw compressor having a compressor housing that has a screw rotor chamber arranged in the compressor housing, two screw rotors that are arranged in the screw rotor chamber and are mounted on the compressor housing to be rotatable about a respective screw rotor axis, and at least one control slider, which is arranged in a slider channel of the compressor housing, is adjacent to both screw rotors and is movable in a direction of displacement parallel to the screw rotor axes and takes a form such that it affects the final volume and/or the initial volume, wherein there is provided on the screw compressor a compressor operational control unit that takes a form such that it performs a compressor operating function that assists at least one operation of the compressor unit.

1 . A compressor unit, comprising:
 a screw compressor having a compressor housing that has a screw rotor chamber arranged in the compressor housing;   at least one screw rotor that is arranged in the screw rotor chamber, and is mounted on the compressor housing to be rotatable about a screw rotor axis and to receive a gaseous medium having an initial volume that is supplied by way of a low-pressure chamber arranged in the compressor housing, and to discharge the gaseous medium, compressed to a final volume, in the region of a high-pressure chamber arranged in the compressor housing; and   at least one control slider arranged in a slider channel of the compressor housing, and which is adjacent to the screw rotor, the at least one control slider being movable in a direction of displacement parallel to the screw rotor axis and being configured such that the at least one control slider affects the final volume and/or the initial volume;   wherein the screw compressor has a compressor operational control unit configured to perform a compressor operating function, which is an operation assisting function that assists at least one operation of the compressor unit.   
     
     
         2 . The compressor unit according to  claim 1 , wherein the operation assisting function, that assists the at least one operation of the compressor unit, is a parameter determining function, and in order to perform the parameter determining function, the operation assisting function determines at least one of the following function parameters:
 pressure of the gaseous medium on an input side of the screw compressor;   temperature of the gaseous medium on the input side of the screw compressor;   pressure of the gaseous medium on an output side of the screw compressor;   temperature of the gaseous medium on the output side of the screw compressor;   a position of the at least one control slider;   lubricant temperature;   lubricant flow rate;   lubricant differential pressure at a lubricant filter;   lubricant level in at least one lubricant supply line;   speed of rotation of a drive motor;   temperature of the drive motor;   phasing of the drive motor;   voltage at the drive motor; and   current consumption of the drive motor.   
     
     
         3 . The compressor unit according to  claim 2 , wherein the compressor operating function is a protective function, and in order to perform the protective function, at least one additional parameter determining function is performed, in which at least one of the function parameters is compared with at least one corresponding reference parameter, such that if a value of the at least one of the function parameters exceeds or falls below that of the at least one corresponding reference parameter, a warning message is given and/or the screw compressor is switched off. 
     
     
         4 . The compressor unit according to  claim 1 , wherein the operation assisting function, that assists the at least one operation of the compressor unit, is a control function, and in order to perform the control function, at least one of the following units is controlled:
 a control slider drive;   a motor controller;   a lubricant cooling unit;   an injection element for compressed medium for the purpose of additional cooling;   a slider controller for the at least control slider.   
     
     
         5 . The compressor unit according to  claim 1 , wherein the operation assisting function, that assists the at least one operation of the compressor unit, is an operating state predetermining function in which a control function is performed on the basis of at least one request signal, or at least one function parameter, communicated to the compressor operational controller. 
     
     
         6 . The compressor unit according to  claim 1 , wherein the operation assisting function, that assists the at least one operation of the compressor unit, is an operating state monitoring function, and for the purpose of performing the operating state monitoring function, a parameter detected by at least one parameter determining function and/or a result of at least one protective function and/or a control operation of at least one control function is recorded. 
     
     
         7 . The compressor unit according to  claim 6 , wherein the recording of the at least one function parameter and/or a performance of at least one protective function and/or a performance of the at least one control function take place over time. 
     
     
         8 . The compressor unit according to  claim 1 , wherein the compressor operational control unit is provided with a communication unit for exchanging data with external devices. 
     
     
         9 . The compressor unit according to  claim 8 , wherein the communication unit exchanges the data wirelessly or by a wired route. 
     
     
         10 . The compressor unit according to  claim 1 , wherein the compressor operational control unit is provided with at least one display unit that shows at least one performance state of at least one compressor operating function or the result thereof. 
     
     
         11 . The compressor unit according to  claim 1 , wherein the screw compressor has a controller housing in which the compressor operational controller is arranged. 
     
     
         12 . The compressor unit according to  claim 11 , wherein the controller housing is arranged on the compressor housing. 
     
     
         13 . The compressor unit according to  claim 1 , wherein the screw compressor has two screw rotors that are arranged in the screw rotor chamber, are mounted on the compressor housing to be rotatable about the respective screw rotor axis, engage in one another by their helical contours and each interact with compression wall surfaces that are adjacent to and partly surround the helical contours in order to receive the gaseous medium having the initial volume that is supplied by way of the low-pressure chamber arranged in the compressor housing and to discharge the gaseous medium, compressed to the final volume, in the region of the high-pressure chamber arranged in the compressor housing, in that the gaseous medium is enclosed, at low pressure and with the initial volume, in compression chambers formed between the helical contours and compression wall surfaces adjacent thereto, and is compressed to the final volume at high pressure, wherein the at least one control slider, which is arranged in the slider channel of the compressor housing, is adjacent to both screw rotors by slider compression wall surfaces, and is movable in the direction of displacement parallel to the two screw rotor axes, and is configured such that the at least one control slider affects the final volume and/or the initial volume. 
     
     
         14 . The compressor unit according to  claim 1 , wherein a position determining device is provided for the at least one control slider, in that the position determining device has a position indicator element coupled to the at least one control slider, wherein the position indicator element interacts with a detector element that extends parallel to the direction of displacement of the at least one control slider and along which the position indicator element is movable, and wherein the detector element is coupled to an evaluation device that determines a position of the position indicator element along the detector element. 
     
     
         15 . The compressor unit according to  claim 14 , wherein the detector element is arranged in a detector channel that extends inside the compressor housing, parallel to the direction of displacement. 
     
     
         16 . The compressor unit according to  claim 15 , wherein the position indicator element is arranged in the detector channel. 
     
     
         17 . The compressor unit according to  claim 14 , wherein the position indicator element is mechanically coupled to the at least one control slider via a connection body. 
     
     
         18 . The compressor unit according to  claim 14 , wherein the position indicator element interacts with the detector element in a contactless manner. 
     
     
         19 . The compressor unit according to  claim 1 , wherein the compressor operational controller controls a control slider drive for the at least one control slider, and determines movement of the at least one control slider using a position determining unit. 
     
     
         20 . The compressor unit according to  claim 19 , wherein the compressor operational control unit positions the at least one control slider with position control. 
     
     
         21 . The compressor unit according to  claim 1 , wherein, when determining the positions of the at least one control slider, the compressor operational controller takes into account at least one of the parameters:
 pressure level on an input side at low pressure;   pressure level on an output side at high pressure;   temperature of the gaseous medium on the input side at low pressure;   temperature of the gaseous medium on the output side at high pressure;   speed of rotation of the screw rotors;   power consumption of a drive motor;   parameters of the gaseous medium; and   values of limits of use of the screw compressor.   
     
     
         22 . The compressor unit according to  claim 1 , wherein the at least one control slider includes a first control slider and a second control slider which are arranged one behind the other in the direction of displacement. 
     
     
         23 . The compressor unit according to  claim 22 , wherein the first control slider and the second control slider have identical external contours. 
     
     
         24 . The compressor unit according to  claim 22 , wherein the first control slider and the second control slider are positionable directly succeeding one another in a combined position and are movable together in the direction of displacement. 
     
     
         25 . The compressor unit according to  claim 22 , wherein the first and the second control slider are positionable in a separated position, spaced from one another, forming an intermediate space. 
     
     
         26 . The compressor unit according to  claim 22 , wherein the first control slider has mutually directly adjacent slider compression wall surfaces, where, in each case, one is adjacent to one of the screw rotors, and wherein the second control slider has slider compression wall surfaces that are spaced from one another where, in each case, one is adjacent to one of the screw rotors. 
     
     
         27 . The compressor unit according to  claim 26 , wherein the first control slider is mounted on the second control slider. 
     
     
         28 . The compressor unit according to  claim 26 , wherein the slider compression wall surfaces of the first control slider and of the second control slider succeed one another.