公开(公告)号：US20200162004A1

公开(公告)日：2020-05-21

申请号：US16634423

申请日：2018-07-23

Applicant: Edwards Limited

Inventor： Jian Li ,  James Alexander Haylock

IPC: H02P21/36 ,  H02P21/00 ,  H02P21/22 ,  H02P27/12

Abstract: A method of controlling an induction motor, an apparatus and a computer program product are disclosed. The method comprises: in response to an indication that a rotational frequency of the rotor is to be reduced from an initial operating frequency to a reduced operating frequency, applying an alternating braking voltage to the stator, the alternating braking voltage having a frequency selected to provide a slip of less than around −1. In this way, the applied to alternating braking voltage generates a negative torque to slow the rotor while ensuring that a large proportion of the power generated by the motor is dissipated within the motor itself. This helps to reduce the amount of power required to be dissipated by any driving circuitry.

公开(公告)号：US20190226914A1

公开(公告)日：2019-07-25

申请号：US16330306

申请日：2017-09-06

Applicant: Edwards Limited

Inventor： Brent Haslett ,  Andrew Grantham ,  James Alexander Haylock

IPC: G01J5/06 ,  F04D19/04 ,  F04D27/00 ,  G01J5/00 ,  G01J5/02 ,  G01J5/04 ,  G01J5/12

Abstract: Infra-red sensors are often used in turbo molecular pumps to detect the temperature of the rotor or other mechanical parts and therefore indicate imminent, or potential, running failures.As deposits build up on either the infra-red sensor, or on the surface being monitored, the reading given by the sensor may not be a true representation of the actual surface temperature which can cause the pump controller to fail to stop the pump in time.The present invention provides a method and device for calibrating the sensor by creating a determined temperature rise in the sensor whilst keeping the rotor at ambient temperature. In particular the present invention uses the motor stator as the heater for causing the temperature increase.

公开(公告)号：US20240093692A1

公开(公告)日：2024-03-21

申请号：US18256551

申请日：2021-12-14

Applicant: Edwards Limited

Inventor： James Alexander Haylock ,  Christopher Miles ,  Alexander James Patey

IPC: F04D27/00 ,  F04D29/056 ,  G01M13/04

CPC classification number: F04D27/001 ,  F04D29/056 ,  G01M13/04

Abstract: A monitoring apparatus includes: input reception circuitry configured to receive a signal indicative of a characteristic of rotating assembly rotation; and bearing wear monitoring circuitry configured to analyze the signal characteristic of rotating assembly rotation. The bearing wear monitoring circuitry is also configured to identify one or more signal features indicative of bearing wear. Bearing wear produces variation in rolling friction of the bearing and therefore is one cause of variation in shaft torque. Aspects recognise that variations in shaft torque can be indirectly monitored, measured and/or determined by appropriate measurement or monitoring of operational characteristics of a pump motor and that it may be possible to distinguish variations in shaft torque which can be attributed to bearing wear from those variations in shaft torque caused by one or more other factors.

公开(公告)号：US10514040B2

公开(公告)日：2019-12-24

申请号：US15310841

申请日：2015-05-13

Applicant: EDWARDS LIMITED

Inventor： James Alexander Haylock ,  Richard Lee Harkin ,  Ian Keech ,  Jian Li

IPC: F04D27/00 ,  F04D19/04 ,  F04D17/16 ,  F04D29/58 ,  F04D25/06 ,  F04B39/06 ,  F04B53/08 ,  F04C25/02

Abstract: A vacuum system includes a vacuum pump and an electric motor for driving the vacuum pump. A cooling arrangement cools the vacuum system. A control performs at least one of decreasing voltage and increasing frequency of a signal applied to the electric motor to decrease an amount of magnetic flux generated in the electric motor instead of decreasing the current applied to the electric motor to arrive at a desired torque generated by the electric motor in response to pumping requirements of the vacuum pump.

公开(公告)号：US20190162748A1

公开(公告)日：2019-05-30

申请号：US16309379

申请日：2017-05-16

Applicant: Edwards Limited

Inventor： James Alexander Haylock ,  Alexander James Patey ,  Michael Simmonds

IPC: G01P15/08 ,  F04D25/06 ,  F04D27/00

Abstract: A pump assembly method and computer program are disclosed. The pump assembly comprises: a pump, an associated motor controller and an accelerometer mounted on the pump. The motor controller is configured to control power supplied to drive the pump and to receive data output from the accelerometer, the motor controller comprising processing circuitry configured to process the data received from the accelerometer to determine accelerations experienced at the pump due to the pump operation. These accelerations can be used to determine a condition of the pump.