Method for monitoring and regulating coolant temperature of drive of separator

Abstract

The invention relates to a method for adjusting the coolant temperature of an electric motor of a drive (8) of a rotor of a centrifuge, preferably a separator (1) having a vertical axis of rotation, in particular during the centrifugal separation of suspended matter into at least two different product phases; wherein the rotor has at least one rotatable cylinder (2), and the drive device has an electric motor (8) which rotates the rotor directly or indirectly, and also has a device (100) for supplying the electric motor with a coolant, the device having a regulating device, the method comprises at least the following steps: a) providing a centrifuge comprising a drive device, b) driving the rotor by means of the electric motor, in particular during a centrifugal separation of the suspension into at least two different product phases, and c) cooling the electric motor in a regulated manner at least during step b) in a cooling cycle interrupted by an interval.

Description

Technical Field

[0001] The invention relates to a method for regulating the coolant temperature of an electric motor of a drive of a rotor of a centrifuge according to the preamble of claim 1 . Background Art

[0002] In order to achieve a compact design in centrifugal separators of this type, the drive of these separators is equipped with an integrated, water-cooled electric motor for directly driving the rotor comprising the separator drum.

[0003] It is known to provide coolant in the required amount and in the permissible temperature range for cooling the electric motor according to the pre-determination of the electric motor manufacturer. In this way, the maximum permissible motor temperature can be maintained. The required inlet amount is limited here, for example, by a corresponding partition or needle valve.

[0004] The additional opening valve opens the coolant supply during operation of the electric motor and closes the coolant supply as soon as the electric motor is switched off. The opening valve for the coolant is permanently open during operation of the drive motor and the coolant flows through the drive motor at a volume flow rate predetermined by the motor manufacturer.

[0005] With this mode of operation, the coolant consumption is always constantly and uniformly high and is independent of the load on the drive motor (product throughput and emptying frequency and size) and the actual temperature of the incoming coolant. Solutions to this problem are therefore known from the prior art.

[0006] DE 38 09 149 C1 describes that the cross section of the coolant outlet line can be varied in stages depending on the coolant outlet temperature of the drive unit (motor).

[0007] DE 20 2007 004 983 U1 describes the use of a water cooling system as a circuit arrangement for cooling a centrifuge drive, which requires a circulation pump and a heat exchanger.

[0008] EP 0 01 6 584 A1 describes the use of a water cooling system which is supplied to a heat exchanger for cooling the centrifuge drive.

[0009] Designs for cooling the electric motor of the separator according to the prior art have proven feasible in practice. The disadvantage in these designs is that the coolant consumption is always high. Summary of the invention

[0010] The object of the present invention is to eliminate the above-mentioned problems.

[0011] The invention achieves this object by the method according to claim 1 .

[0012] A method is proposed for regulating the coolant temperature of an electric motor of a drive device for a rotor of a centrifuge, in particular a separator with a vertical axis of rotation, in particular during the centrifugal separation of a suspended solid into at least two different product phases, wherein the rotor of the centrifuge has at least one rotatable drum and the drive device has an electric motor, which directly or indirectly rotates the rotor, and the drive device also has a device for supplying the electric motor with coolant, the device having a regulating device, wherein the method has at least the following steps:

[0013] a) providing the centrifuge including the driving device;

[0014] b) driving the rotor with the electric motor, in particular driving the rotor with the electric motor during centrifugal separation of the suspension into at least two different product phases, and

[0015] c) Controlled cooling of the electric motor at least during step b) in limited cooling phases in cycles interrupted by intermittent cooling.

[0016] In this case, it can further preferably be provided that the length of the cooling phase of the respective cycle is calculated by the regulating device taking into account one or more measured values, wherein the at least one measured value or the plurality of measured values ​​can be temperature measured values.

[0017] Compared to uninterrupted continuous cooling, the coolant consumption is usually significantly reduced by periodic cooling. In cooling systems designed in the manner of a circuit, it is possible to work with a reduced coolant volume per time unit, or less coolant moves in the circuit.

[0018] According to a particularly advantageous variant, it is provided that the cycle of step c) has the following sub-steps:

[0019] c1) opening an opening valve of the coolant supply system to cause coolant to flow through a cooling fluid system of the electric motor, the cooling fluid system having at least one coolant input line and a coolant output line and a motor coolant delivery device;

[0020] c2) After a predetermined time t 测量 Then, the instantaneous temperature T of the coolant is measured by a temperature measuring device at the coolant output pipeline. 瞬时 And will be used for T 瞬时 The measured value of the temperature measuring device is transmitted to a regulating device, wherein the predetermined time t is determined as a function of the length of the coolant outlet line between the electric motor and the temperature measuring device 测量 ;

[0021] c3) T瞬时 The measured value and the upper limit value T of the coolant temperature 界限 Make comparisons;

[0022] c4) By adjusting the device according to T 瞬时 To calculate the time t 冷却 , during the time, the opening valve is additionally kept open;

[0023] c5) After t 测量 and t 冷却 After that, during the cycle interval t 间歇 Internal closed open valve;

[0024] Then after passing t 间歇 Thereafter, method steps c1) to c5) are repeated almost continuously in a program loop until the operation of the drive motor of the centrifuge ends.

[0025] This results in the following total cycle time: t 周期 =t 测量 +t 冷却 +t 间歇

[0026] This provides a method for monitoring and regulating the coolant temperature of a centrifuge, wherein the instantaneous coolant temperature can be kept as constant as possible at a defined upper coolant temperature limit value. In this way, the electric motor of the separator is operated at the maximum permissible temperature and the minimum possible coolant consumption, and more precisely, independently of its load, the ambient temperature and the temperature of the incoming coolant.

[0027] Another advantage of the method according to the invention or the separator including the correspondingly equipped regulating device is that it can be easily retrofitted to existing coolant-cooled electric motors, since for this purpose, in terms of hardware, essentially only a temperature measuring device at the coolant outlet line must be added. A temperature sensor inside the electric motor is not required, although it can be provided. In addition, only a simple valve with two switching positions ("open" and "closed") is required as an opening valve. Therefore, no regulating valve or adjustable aperture throttle valve is required, as in the solutions according to the prior art, and no multiple valves and lines are required, as in the solutions according to the prior art.

[0028] In addition, a computer program product is stored and executed on the control device or on another memory connected or connectable thereto, the computer program product having instructions which cause the method steps of the method for periodically cooling the electric motor, in particular the method steps according to one of claims 1 to 14, to be executed on the separator for cooling the drive.

[0029] According to a particularly preferred embodiment variant of the invention, it is provided that if the instantaneous coolant temperature T 瞬时 The upper limit value T of the coolant temperature 界限 Below, directly in the time period t 测量 The opening valve is then closed. As a result, the coolant can absorb thermal energy up to a defined upper limit temperature for the coolant, so that the required coolant volume flow can be advantageously reduced.

[0030] According to another particularly preferred embodiment variant of the invention, it is provided that if the instantaneous coolant temperature T 瞬时 is greater than or equal to the upper limit value T of the coolant temperature 界限 , then the open valve is opened at another time t 冷却 As a result, the increased coolant temperature is reduced to a defined upper limit temperature for the coolant, while the coolant volume flow required for this purpose is advantageously minimized.

[0031] Furthermore, according to another particularly preferred embodiment of the present invention, it can be provided that T 瞬时 and t 冷却 A mapping table of measured values ​​of T is obtained, from which a centrifuge-specific or coolant supply system-specific characteristic curve is obtained, which represents T 瞬时 With t 冷却 , so that the coolant temperature control is designed as a characteristic curve control. This results in an advantageously simple operating principle of the coolant control, which can be individually adapted to the corresponding separator.

[0032] Alternatively, according to another particularly preferred embodiment variant of the invention, provision can be made in step c) to transfer the current coolant temperature T 瞬时 One or more measured values ​​of the ambient temperature and preferably additionally one or more measured values ​​of the ambient temperature and one or more current motor load characteristic values ​​are supplied to the regulating device (in particular a higher-order control device of the separator), which then determines the cooling time t using these measured values ​​in accordance with an algorithm. 冷却 If the coolant temperature does not change in the desired direction after a number of subsequent cooling cycles, the algorithm is adapted by the regulating device, preferably by a superordinate control device, until the coolant temperature reaches the value T 界限 By means of this adaptability of the algorithm, the control can be adapted particularly advantageously to changing operating conditions.

[0033] As an alternative thereto, according to another particularly preferred embodiment variant of the invention, provision can be made to use a PID controller as the regulating device. This advantageously makes it possible to monitor and regulate the coolant temperature particularly flexibly.

[0034] The invention can be used in structurally different cooling system variants.

[0035] According to another particularly preferred embodiment variant of the invention, it can also be provided that the coolant supply system is designed according to the principle of a closed coolant circuit.

[0036] According to another particularly preferred embodiment variant of the invention, it is provided that the coolant is sucked in the circuit by means of a pump and cooled by means of a heat exchanger and that the required cooling capacity is supplied to the heat exchanger via a refrigeration circuit.

[0037] Furthermore, according to another particularly preferred embodiment variant, provision can be made for the coolant to be removed from a storage tank and, after flowing through the electric motor and absorbing heat, to be pumped back into the storage tank. This results in an open circuit into which coolant can be supplied or removed as required. This is advantageous, for example, in the event of brief peak loads. In this variant, the coolant consumption is also advantageously minimized effectively.

[0038] In this case, according to another preferred embodiment variant, it can be provided that the heat absorbed by the coolant is released back to the surroundings of the storage tank by convection via the wall of the storage tank, thereby advantageously effectively minimizing the possible coolant refilling volume, thereby advantageously saving coolant.

[0039] It is particularly advantageous if the wall of the storage tank is equipped with suitable means for improving convective heat dissipation. This further advantageously effectively minimizes the possible refill volume of coolant, thereby advantageously saving coolant.

[0040] The invention also provides a separator, comprising a regulating device and other components, which is adapted so that it implements the method steps according to one of the above claims. In addition, the invention provides a computer program product having commands or instructions, which cause the separator of claim 15 to implement the method steps according to one of claims 1 to 14. A computer-readable medium is also provided, on which the computer program is stored.

[0041] Further advantageous embodiments of the invention can be gathered from the remaining dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The invention is described in more detail below with reference to the accompanying drawings using exemplary embodiments. The invention is not limited to these exemplary embodiments but can also be implemented in another way, either literally or in another way, which is equivalent. In the accompanying drawings:

[0043] Figure 1 shows a schematic cross-sectional view of a separator including a coolant supply system for a drive motor;

[0044] Figure 2 A simplified circuit diagram showing a coolant supply system for a separator;

[0045] Figure 3 Show Figure 2 A variant implementation of a coolant supply system;

[0046] Figure 4 Show Figure 2 Another embodiment of the coolant supply system; and

[0047] Figure 5 A flow chart is shown for illustrating an exemplary method according to the present invention; and

[0048] Figure 6 Shown for illustration purposes Figure 5 Another flowchart of the sub-steps of . DETAILED DESCRIPTION

[0049] In the following description of the drawings, several exemplary embodiments are described. Individual features of these exemplary embodiments can also be combined with exemplary embodiments not shown and are also suitable as advantageous embodiments of individual or multiple subjects described in the independent and dependent claims.

[0050] Figure 1 A centrifuge is shown, which can be configured as a separator 1. The centrifuge (here a separator) has a rotor. The rotor has a rotatable barrel 2, which has a vertical axis of rotation D here. The barrel 2 can be surrounded by a cover arrangement 3. Terms such as "upper" and "lower" refer to an exemplary vertical arrangement of the barrel 2 below. The barrel 2 is mounted on a drive shaft 4. The drive shaft is rotatably supported in a bearing housing 7 with a bearing assembly, which here has an upper bearing 5 and a lower bearing 6. The bearing assembly has two rolling bearings by way of example. Other designs are conceivable (not shown here).

[0051] The drive of the separator has an electric motor 8 for rotating a rotor comprising the drum 2. The electric motor 8 has a motor housing 9 with a stator 10 or stator winding and with a motor rotor or rotor 11.

[0052] The electric motor 8 advantageously does not have its own bearing device here, which allows a cost-effective design. The bearing arrangement is instead arranged here by way of example between the electric motor 8 and the drum 2. However, the bearing arrangement can also be realized in another way.

[0053] The drive shaft 4 can also be connected to the rotating part 11 directly (i.e. preferably without intermediate elements, such as couplings) by way of example. In contrast, the motor housing 9 including the stator 10 can be arranged rigidly and non-elastically on the frame 12 of the separator 1 or supported thereon.

[0054] In this way, the cylinder 2 including the drive shaft 4, the rotating member 11 and the supporting shell 7 constitute a vibration unit, which is elastically supported on the frame 12, but the stator 10 does not belong to the vibration unit, so that relative movement occurs between the rotating member 11 and the stator 10.

[0055] The drive shaft 4 is arranged in a hole-like opening 13 of a one-piece or multi-piece bearing housing 7 by means of the bearing 5 and the bearing 6 .

[0056] The bearing housing 7 has an upper flange 14 and a sleeve-shaped lower section 15 which extends through an opening 16 in the machine frame 12 .

[0057] The upper flange 14 is supported on the frame 12 via circumferentially distributed elastic damper elements 17 which are distributed between the underside of the flange 14 and the upper side of the frame 12 , wherein the flange 14 and the frame 12 are provided with annular steps 18 , 19 in the region of the damper elements 17 .

[0058] Furthermore, a lubricant supply device 20 may be provided for supplying the bearings 5 ​​, 6 with lubricating material.

[0059] In this regard, the present description relates to advantageous embodiments but is not limited to the described configuration. On the contrary, the coolant supply system and the method associated therewith described below can be used in the above-described separator but also in separators having other configurations.

[0060] According to the centrifuge of the present invention (e.g. Figure 1The coolant supply system 100 (structured like a separator of a motor) has a coolant supply system 100, which supplies coolant to the drive device or its electric motor 8 here. A fluid, especially water, can be provided as a coolant. Other suitable fluids can also be used as coolants. The coolant supply system 100 has at least one coolant supply line 101 (also called a coolant inlet) and a coolant outlet line 102 (also called a coolant return). A motor coolant delivery device 113 is arranged between the coolant supply line and the coolant outlet line, and the motor coolant delivery device can be guided through elements of the electric motor and / or guided past it. The actual cooling of the electric motor 8, especially the stator here, occurs here, and the electric motor heats the coolant in the section. The coolant supply system 100 can have other elements, such as one or more controllable valves.

[0061] exist Figure 2 In particular, separators (e.g. Figure 1 1 ). The coolant supply system 100 here again has a coolant outlet line 102, a coolant inlet line 101 and a motor coolant delivery device 113 which are respectively connected to the electric motor 8. A controllable opening valve 103 can be provided in the coolant inlet line 101. The opening valve 103 is designed to be controllable. The opening valve can preferably be opened and closed by an actuator controlled by a regulating device 105 with electrical or electromagnetic action. However, the operation of the opening valve 103 can also be realized in another way as an alternative.

[0062] Figure 2 The coolant outlet pipeline 102 of the embodiment of the present invention now has a temperature measuring device 104. The temperature measuring device 104 can be constructed as a resistance temperature sensor, for example. The temperature measuring device 104 can also be constructed in another way. The coolant supply system 100 also has a regulating device 105. The regulating device 105 can be constructed as an independent regulating device that only undertakes coolant regulation. The regulating device can also be integrated into the upper-level control device of the separator instead. It is designed to receive the measured value of the temperature measuring device 104. The temperature measuring device 104 is connected to the regulating device 105 so that the regulating device can process the detected measured value. The regulating device 105 is also designed to control the actuator, such as the valve 103 in particular, directly or via an intermediately connected control device according to the type of the control device.

[0063] The regulating device 105 may have a microprocessor and an interface as well as other control components connected in between, such as a gateway and a module connected downstream thereof, by means of which the regulating device can be connected at least to a controllable actuator (such as an opening valve 103) and one or more sensors (such as a temperature measuring device 104). The connection can be made via a wired or non-wired data transmission line.

[0064] A method described below is provided for monitoring and regulating the coolant temperature of the drive of the separator 1 , with which the coolant volume flow through the electric motor 8 of the separator drive is metered in an actively controlled manner.

[0065] For this purpose, it can be advantageously and simply provided that the regulating device 105 opens and closes the opening valve 103 in a pulsed manner during the operation of the separator or during the operation of the drive with the electric motor 8 serving as the drive in a cooling cycle, wherein the duration of the opening pulse depends on the measured temperature T of the coolant at the coolant outlet line 102 of the electric motor. 瞬时 , which is measured by the temperature measuring device 104. This operating method achieves a very low coolant consumption. Thus, compared to the specifications of the motor manufacturer, it is often possible to achieve a reduction in coolant consumption and, for example, a permanent reduction in water consumption.

[0066] First, the centrifuge (including its drive) is provided and the rotor is set into rotation by means of the electric motor 8, and the centrifugation process is started ( Figure 5 - Steps a, b).

[0067] During the rotation of the rotor (starting from said rotation), periodic cooling also starts in parallel ( Figure 5 Step c), wherein the sub-steps of step c) can then be repeated continuously during the centrifugation (see Figure 6 ).

[0068] At the beginning of each cooling cycle, in particular in the case of centrifugal separation, the motor 8 which is in operation and which rotates the drive shaft 4 of the separator 1 is operated for a defined period of time t 测量 The opening valve 103 is opened for coolant delivery to the drive motor ( Figure 6 - Step c1), whereby the heated coolant is pressed from the motor coolant delivery device 113 (eg the cooling jacket of the electric motor 8) into the coolant outlet line 102, in which the temperature measuring device 104 is also located. The temperature measuring device measures the temperature at the time t 测量 The instantaneous coolant temperature T 瞬时And the measured value is transmitted to the regulating device 105. In order to ensure the correct detection of the coolant temperature, the time t can be appropriately selected according to the length of the coolant outlet pipeline 102 between the motor 8 and the temperature measuring device 104 according to the experience of the previous cycle or other measured values ​​of similar centrifuges. 测量 The regulating device 105 is based on T 瞬时 Calculate the additional time t 冷却 , the opening valve 103 is additionally kept open during the additional time.

[0069] If the measured value T 瞬时 At the upper limit value T of the coolant temperature 界限 (e.g. 40°C), then the temperature may be directly 测量 The opening valve 103 is then closed again.

[0070] If the measured value T 瞬时 At the upper limit value T of the coolant temperature 界限 Above, at the time t 冷却 The opening valve 103 continues to be opened.

[0071] T can be obtained through experiments 瞬时 and t 冷却 This results in a centrifuge-specific or coolant supply system-specific characteristic curve, which represents T 瞬时 With t 冷却 The relationship between makes the coolant temperature control constructed as a characteristic curve control.

[0072] Alternatively, measured values ​​of the current coolant temperature, possibly the ambient temperature and possibly the engine load can be supplied to the control device (105). The control device supplies these measured values ​​to a suitable ascertainment of the cooling time t 冷却 If the coolant temperature does not change in the desired direction after a number of subsequent cooling cycles, the algorithm is adapted by the control device until the coolant temperature reaches the value T 界限 By means of this intelligent adaptability of the algorithm, the control can be adapted independently and particularly advantageously to changing operating conditions.

[0073] Alternatively, a PID controller can be used which is configured accordingly so that the limit value control is realized with a parameterizable controller, by which t 冷却 According to T 瞬时 Calculated separately.

[0074] After t 测量 and t 冷却After that, the valve 103 is opened for a period of time t 间歇 After that, the cooling cycle restarts. Therefore, by t 测量 ,t 冷却 and t 间歇 The sum of the total cycle time t 周期 .

[0075] The corresponding cycle is thus structured in a simplified manner as follows and has the following sub-steps:

[0076] c1) opening the opening valve 103 of the coolant supply system 100 to cause coolant to flow through the cooling fluid system of the electric motor 8;

[0077] c2) After a predetermined time t 测量 Then, the instantaneous temperature T of the coolant is measured at the coolant output pipeline 102 by the temperature measuring device 104. 瞬时 And will be used for T 瞬时 The measured value is transmitted to a control device 105, wherein the predetermined time t is determined as a function of the length of the coolant outlet line 102 between the electric motor (8) and the temperature measuring device 104. 测量 ;

[0078] c3) T 瞬时 The measured value and the upper limit value T of the coolant temperature 界限 Make comparisons;

[0079] c4) The regulating device 105 is used according to T 瞬时 To calculate the time t 冷却 , during the time, the opening valve 103 is additionally kept open;

[0080] c5) After t 测量 and t 冷却 After that, during the cycle interval t 间歇 The opening valve 103 is closed internally;

[0081] Then after passing t 间歇 Thereafter, the method steps c1) to c5) are repeated “almost continuously” in a program loop until the operation of the drive motor of the centrifuge ends.

[0082] Thus, method steps c1) to c5) are always repeated or cyclically performed with the aid of the control device 105 , preferably until the operation of the drive motor has ended. The program is then interrupted.

[0083] The purpose of the coolant temperature control according to the present invention is to adjust the instantaneous coolant temperature T 瞬时Keep T as constant as possible 界限 (Specified by the manufacturer). In this way, the electric motor 8 is operated at the maximum permissible temperature and the minimum possible coolant consumption, and more precisely independently of its load and the temperature of the incoming coolant.

[0084] The specifications of the motor manufacturer regarding the volume flow of the inflowing coolant are usually static specifications for the rated load of the motor 8. For example, a volume flow of 3 l / min is specified at a maximum coolant temperature of 40° C. and a rated load of 37 kW.

[0085] In practice, such operating points hardly occur without coolant temperature control. Either the electric motor 8 is operated at partial load and / or the coolant inlet temperature is below the maximum permissible temperature. Therefore, more coolant is usually supplied to the electric motor 8 per time unit than is required by the operating conditions of the electric motor 8. This disadvantage is eliminated in a simple manner by the present invention.

[0086] Another advantage of the measuring and regulating arrangement is that it can be easily retrofitted to existing coolant-cooled electric motors, since only a temperature measuring device 104 must be added to the coolant outlet line 102 for this purpose. A temperature sensor inside the electric motor 8 (for example in the coolant chamber) is not required. In addition, only a simple valve with two switching positions (“open” and “closed”) is required as the opening valve 103. Therefore, no regulating valve or adjustable aperture throttle valve is required, as in the solutions according to the prior art, and no multiple valves and lines are required, as in the solutions according to the prior art.

[0087] exist Figure 3 In the embodiment, the coolant supply system 100 is constructed according to the principle of a closed coolant circuit. This further reduces the coolant consumption. For this purpose, it is provided that the coolant is sucked in the circuit by means of a pump 106 and cooled by means of a heat exchanger 107. The required cooling power is supplied to the heat exchanger 107 via a refrigeration circuit 108.

[0088] In the coolant supply system 100, Figure 4In another embodiment variant, the coolant is taken from the storage tank 109 and pumped back into the storage tank 109 after flowing through the electric motor and absorbing heat. The heat absorbed by the coolant is released to the surroundings of the storage tank 109 via the wall 110 of the storage tank 109, in particular by convection. The wall 110 of the storage tank 109 can be equipped with suitable means for improving convection heat dissipation, such as cooling fins. If the heat capacity of the coolant in the storage tank 109 and the heat dissipation by convection are not sufficient, the overheated coolant can be discharged via the first line 111 and the cold coolant can be conveyed via the second line 112.

[0089] The following application example of the method according to the invention for monitoring and regulating the coolant temperature for a separator 1 shows a considerable coolant saving with a coolant-cooled drive motor (designed here as a three-phase AC motor) having, for example, the following performance data:

[0090] P ab =37kW

[0091] P auf =40kW

[0092] Coolant volume flow: 3 l / min (predetermined by the manufacturer)

[0093] Maximum cooling water temperature: 40°C (predetermined by the manufacturer)

[0094] The parameters for the coolant control are obtained as follows:

[0095] t 测量 : 2 seconds

[0096] t 冷却 : 2 seconds

[0097] t 间歇 : 6 seconds

[0098] t 周期 : 10 seconds

[0099] Test 1: (Measurement after thermal stabilization operation)

[0100] Load: 35.9kW

[0101] Coolant inlet temperature: 23.1°C

[0102] Coolant discharge temperature: 40.8°C

[0103] Coolant volume flow: 1.85 l / min

[0104] Temperature increase: 17.7K

[0105] Test 2: (Measurement after thermal stabilization operation)

[0106] Load: 26.3kW

[0107] Coolant inlet temperature: 23.5°C

[0108] Coolant discharge temperature: 40.9°C

[0109] Coolant flow rate: 1.73l / min

[0110] Temperature increase: 17.4K

[0111] It has been shown that the coolant requirement can advantageously be kept small. Reference numerals list

[0112] 1 separator

[0113] 2 barrels

[0114] 3-hood layout structure

[0115] 4 drive shaft

[0116] 5 Upper bearing

[0117] 6 Lower bearing

[0118] 7 Support housing

[0119] 8 Electric Motor

[0120] 9Motor housing

[0121] 10 Stator

[0122] 11 Rotors

[0123] 12 racks

[0124] 13 Opening

[0125] 14 Flange

[0126] 15 sectors

[0127] 16 Opening

[0128] 17 Buffer element

[0129] 18 steps

[0130] 19 steps

[0131] 20 Lubricant supply device

[0132] 100 Coolant Supply System

[0133] 101 Coolant input pipeline

[0134] 102 Coolant output pipeline

[0135] 103 open valve

[0136] 104 Temperature measurement equipment

[0137] 105 Adjustment equipment

[0138] 106 Pumps

[0139] 107 Heat Exchanger

[0140] 108 Refrigeration Circuit

[0141] 109 Storage Tanks

[0142] 110 wall

[0143] 111 First pipeline

[0144] 112 Second pipeline

[0145] 113 Motor coolant delivery device

[0146] D Rotation axis

Claims

1. A method for regulating the coolant temperature of an electric motor of a drive device (8) of a rotor of a centrifuge, the centrifuge preferably being a separator (1) with a vertical axis of rotation, in particular during the centrifugal separation of a suspended solid into at least two different product phases; the rotor having at least one rotatable drum (2), and the drive device having an electric motor (8) which directly or indirectly rotates the rotor, and also having a device (100) for supplying the electric motor with coolant, the device having a regulating device (105), characterized in that The method comprises at least the following steps: a) providing the centrifuge including the driving device; b) driving the rotor with the electric motor, in particular driving the rotor with the electric motor during centrifugal separation of the suspension into at least two different product phases, and c) Controlled cooling of the electric motor at least during step b) in limited cooling phases in cooling cycles interrupted by intermittent cooling.

2. The method according to claim 1, characterized in that The length of the respective cooling phase is ascertained by the control device (105) taking into account one or more measured values.

3. The method according to claim 2, characterized in that The length of the corresponding cooling phase is ascertained by the control device (105) taking into account one or more temperature measured values.

4. The method according to claim 1, characterized in that The cooling cycle of step c) has the following sub-steps: c1) opening an opening valve (103) of the coolant supply system (100) to cause coolant to flow through a cooling fluid system of the electric motor (8), the cooling fluid system having at least one coolant input line (101) and a coolant output line (102) and a motor coolant delivery device (113); c2) After a predetermined time t 测量 Then, the instantaneous temperature T of the coolant is measured at the coolant output pipeline (102) by a temperature measuring device (104). 瞬时 and the instantaneous temperature T of the coolant 瞬时 The measured value is transmitted to a control device (105), and the predetermined time t is determined according to the length of the coolant outlet line (102) between the electric motor (8) and the temperature measuring device (104). 测量 ; c3) The instantaneous temperature T of the coolant 瞬时 The measured value and the upper limit value T of the coolant temperature 界限 Make comparisons; c4) adjusting the instantaneous temperature T of the coolant by the regulating device (105) 瞬时 To calculate the time t 冷却 , during the time, the opening valve (103) is additionally kept open; c5) After the predetermined time t 测量 and the time t 冷却 After that, during the cycle interval t 间歇 Closing the opening valve (103) internally; Then, after the cycle interval time t 间歇 Thereafter, method steps c1) to c5) are repeated in a program loop until the operation of the electric motor is terminated.

5. The method according to claim 4, characterized in that If the instantaneous coolant temperature T 瞬时 At a predetermined upper limit value T of the coolant temperature 界限 Then in step c5) directly in the time period t 测量 The opening valve (103) is then closed.

6. The method according to claim 4, characterized in that If the instantaneous coolant temperature T 瞬时 The upper limit value T of the coolant temperature is predetermined. 界限 above, the open valve (103) is closed for another period of time t 冷却 Keep it open.

7. The method according to any one of the preceding claims, characterized in that According to the experiment, T 瞬时 and t 冷却 A mapping table of measured values ​​of T is obtained, from which a characteristic curve specific to the centrifuge or coolant supply system is obtained, which represents T 瞬时 With t 冷却 The relationship between and causes the coolant temperature control to be configured as a characteristic curve control.

8. The method according to any one of claims 1 to 7, characterized in that A PID controller is used as the regulating device (105).

9. The method according to any one of the preceding claims, characterized in that In step c), the current coolant temperature T 瞬时 One or more measured values ​​of the ambient temperature and preferably additionally one or more measured values ​​of the ambient temperature and one or more current motor load characteristic values ​​are supplied to the control device (105), which then determines the cooling time t using these measured values ​​in accordance with an algorithm. 冷却 If, after a plurality of subsequent cooling cycles, the coolant temperature does not change in the desired direction, the algorithm is adapted by the control device until the coolant temperature reaches the value T 界限 .

10. The method according to any one of the preceding claims, characterized in that The coolant supply system (100) is constructed according to the principle of a closed coolant circuit.

11. The method according to claim 10, characterized in that The coolant is sucked in the circuit by means of a pump (106) and cooled by means of a heat exchanger (107), and the required cooling capacity is supplied to the heat exchanger (107) via a refrigeration circuit (108).

12. The method according to any one of claims 1 to 9, characterized in that The coolant is taken from the storage tank (109) and, after flowing through the electric motor (8) and absorbing heat, is pumped back into the storage tank (109).

13. The method according to claim 12, characterized in that The heat absorbed by the coolant is released back to the environment of the storage tank (109) by convection via the wall (110) of the storage tank (109).

14. The method according to any one of claims 12 to 13, characterized in that Superheated coolant can be discharged from the storage tank (109) via a first line (111) and cold coolant can be fed into the storage tank (109) via a second line (112).

15. A separator comprising a rotatable rotor and a drive (8) having an electric motor for rotating the rotor, and means adapted to carry out the steps of the method according to one or more of the preceding claims.

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