Arrangement for specifying a pressure

Patent metadata

Field	Value
Publication number	US-10480505-B2
Application number	US-201514942145-A
Country	US
Kind code	B2
Filing date	Nov 16, 2015
Priority date	Sep 30, 2015
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

An arrangement ( 100 ) for specifying the pressure ( 64 ), produced by a pump ( 30 ) driven by an electric motor ( 31 ), includes a processor ( 116 ) which derives a target pressure value ( 62, 118 ) from an internal torque value ( 114 ) and a loss torque ( 108 ). The arrangement ( 100 ) further derives ( 112 ) the internal torque value ( 114 ) from a motor current value ( 110 ) and a motor constant k e .

First claim

What is claimed is:

1. Apparatus ( 100 ) for specifying pressure ( 64 ) generated by a pump ( 30 ) driven by an electric motor ( 31 ), said apparatus comprising:
the electric motor ( 31 ) configured to drive the pump ( 30 );
a source ( 46 , 20 , 16 ) of instantaneous fluid pressure values ( 64 ) and a pressure controller ( 12 ) coupled to an output of said source;
a first processor ( 112 ) configured to calculate an internal torque value ( 114 ) based on a motor current value ( 110 ) and a motor constant k e ;
a second processor ( 116 ) configured to calculate a target pressure value ( 62 ) corresponding to a target pressure of the pump ( 30 ) based on a difference between said internal torque value ( 114 ) and a loss torque value ( 108 ); and
a third processor ( 109 ) configured to calculate said loss torque value ( 108 ) based on a temperature value ( 104 ) and a motor RPM value ( 106 );
wherein a pressure difference is determined based on the difference between an instantaneous pressure of the pump and the target pressure value ( 62 ), and a motor control signal is generated that corresponds to the pressure difference to control the electric motor ( 31 ) to drive the pump ( 30 ) at the target pressure; and
wherein said pressure controller ( 12 ), based upon a difference between an instantaneous fluid pressure value ( 64 ) and a target pressure value ( 62 ), generates a setpoint value ( 118 ) which influences power supplied to said motor ( 31 ), to bring said instantaneous pressure value ( 64 ) toward said target pressure value ( 62 ).

2. The apparatus according to claim 1 , wherein said second processor ( 109 ) uses a performance characteristic matrix ( 102 ) in calculating said loss torque ( 108 ).

3. The apparatus according to claim 1 , wherein said pump is a displacement pump ( 30 ).

4. The apparatus according to claim 2 , wherein said pump is a displacement pump ( 30 ).

5. The apparatus according to claim 1 , wherein said pump is an internal gear pump ( 30 ).

6. The apparatus according to claim 2 , wherein said pump is an internal gear pump ( 30 ).

7. The apparatus according to claim 1 , wherein said pump is a gerotor pump ( 30 ).

8. The apparatus according to claim 2 , wherein said pump is a gerotor pump ( 30 ).

9. The apparatus according to claim 1 , wherein said pressure controller ( 12 ) is a proportional-integrating (PI) controller.

10. The apparatus according to claim 1 , wherein said third processor ( 109 ) uses a performance characteristic matrix ( 102 ) in calculating said loss torque value ( 108 ).

11. A controller for operating a pump ( 30 ) which is driven by an electric motor ( 31 ), comprising
a speed-ramp ( 14 ) which directs motor start-up steps;
a pressure controller ( 12 ) coupled to an output of a source of instantaneous fluid pressure values ( 64 ) and which controls post-start-up operation of the motor, said pressure controller ( 12 ) configure to calculate a target pressure value ( 62 ) corresponding to a target pressure of the pump ( 30 ) based on a difference between an internal torque value ( 114 ) as a function of a motor current value ( 110 ) and a motor constant k e and a loss torque value ( 108 ) as a function of a temperature value ( 104 ) and a motor RPM value ( 106 );
said pressure controller ( 12 ), based upon a difference between an instantaneous fluid pressure value ( 64 ) and a target pressure value ( 62 ), generating a setpoint value ( 118 ) which influences power supplied to said motor ( 31 ), to bring said instantaneous pressure value ( 64 ) toward said target pressure value ( 62 ); and
a changeover switch ( 80 ) which determines when control of said pump is passed from said speed ramp ( 14 ), handling a start-up mode, to said pressure controller ( 12 ), handling a continuous-operation mode.

Assignees

• Ebm Papst St Georgen Gmbh & Co Kg

Inventors

• Hahn Alexander
• Hellmann Marcus
• Kisch Michael
• Loeffler Jens
• Bitzer Manfred

Classifications

• F04C2240/40

  Electric motor · CPC title

• F04C2270/025

  Controlled or regulated · CPC title

• F04C28/06

  specially adapted for stopping, starting, idling or no-load operation · CPC title

• F04B49/06

  Control using electricity (regulating by means of floats actuating electric switches F04B49/04) · CPC title

• H02P1/16

  for starting dynamo-electric motors or dynamo-electric converters · CPC title