Patent US2090905A successfully refreshed from Google Patents.
Patent EP0100390A2 successfully refreshed from Google Patents.
EP0100390A2
Expired / Lapsed
EP
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A method of driving the impeller of a liquid pump by means of a brushless A.C. motor, and a liquid pump for carrying out the method
Assignee: Institut Cerac SA
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Filing: 1982-11-03
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Granted: —
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Expires: 2002-11-03
Abstract
Abstract The invention relates to a method and apparatus for driving the impeller (5) in a turbo-type liquid pump operating at relatively low power and relatively high delivery head by means of an a.c. motor (2). The invention is mainly characterized in that the motor (2) is driven from a static inverter (6) which operates at an operating frequency of 100-1000Hz. This enables high specific speed impellers to be used, and therewith provides a considerable increase in the efficiency and capacity of the pump at unchanged motor sizes.
Inventors
- 👤 Carl Hartwig
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 22:25
CPC Classifications
H; H02; H02P; H02P27/00; H02P27/04; H02P27/06; H02P27/08; F; F04; F04D; F04D15/00; F04D15/0066; F04D29/00; F04D29/66; F04D29/669; H02K; H02K11/00; H02K11/30; H02K11/33
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
89 words
A method of driving by means of a brushless, a.c. motor the impeller of a turbo-type liquid pump operating with relatively low power and high delivery height, characterised by supplying energy to the motor via a static inverter with an output frequency in the order of 100-1000Hz; and by selecting the frequency of the voltage supplied to the motor, the pole number of said motor and the specific speed of the impeller so that the dimensions of the pump are minimised in relation to the flow and/or head desired.
Claim 2
Independent Claim
89 words
A method of driving by means of a brushless, a.c. motor the impeller of a turbo-type liquid pump operating with relatively low power and high delivery height, characterised by supplying energy to the motor via a static inverter with an output frequency in the order of 100-1000Hz; and by selecting the frequency of the voltage supplied to the motor, the pole number of said motor and the specific speed of the impeller so that the dimensions of the pump are minimised in relation to the flow and/or head desired.
Claim 3
Dependent Claim
45 words
A method according to Claim 1, characterized by setting the output frequency of the inverter for a constantly increasing impeller speed; and by setting the.power delivered from the inverter to the motor to a maximum value substantially corresponding to the rated power of the motor.
Claim 4
Dependent Claim
65 words
A method according to Claim 1 or Claim 2, characterized by selecting the pole number of the motor to 2.n, where n is an integer greater than 1. 4. A method according to any one of Claims 1 - 3, characterized in that the output frequency of the inverter is regulated so that the impeller speed is maintained at or beneath a cavitation-free maximum value.
Claim 5
Dependent Claim
41 words
S. A method according to any one of Claims 1 - 4, characterized by utilising the level of the pump fluid to control the inverter in a manner such that the motor speed will not exceed a given maximum idling speed.
Claim 6
Dependent Claim
86 words
A liquid pump for carrying out the method according to Claim 1, comprising an impeller (5) located in a pump casing (1) and arranged to be driven by a brushless, a.c. motor (2), characterized in that a static inverter (6) is arranged to supply energy with an output frequency in the order of 100-1000Hz to said motor; that the impeller has a blade or vane form of the Francis or propeller type; and that the motor is arranged to drive the impeller at high specific speeds.
Claim 7
Dependent Claim
29 words
A liquid pump according to Claim 6, characterized in that the inverter (6) is incorporated in the pump casing (1) together with the motor (2) and the impeller (5).
Claim 8
Dependent Claim
46 words
A liquid pump according to Claim 6 or Claim 7, characterized in that a pressure surge transducer (16) is located adjacent the impeller (5) and arranged to control the inverter (6) such that should cavitation occur the motor speed is reduced to a cavitation-free value .
Claim 9
Dependent Claim
28 words
A liquid pump according to any one of Claims 6 - 8, characterized in that a semi-conductor element, preferably transistors, are used as switching elements in the inverter.
References Cited (Backward Citations)
No citation records indexed.
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