Power control method for a motor of an air-moving device

Abstract

A method to control an input power of a motor of an air-moving device that includes performing a measurement process to determine a first value of an operating parameter of the motor. The operating parameter is an operating pressure of the motor or an airflow rate through the motor. The method includes performing a determination process to determine a value of the inlet restriction of the air-moving device, based on the first value of the operating parameter of the motor and a first pre-determined relationship between values of the operating parameter of the motor and values of an inlet restriction of the air-moving device. The method also includes controlling, based on the determined value of the inlet restriction, the input power of the motor.

1 . A method to control an input power of a motor of an air-moving device, the method comprising:
 performing a measurement process to determine a first value of an operating parameter of the motor, wherein the operating parameter is an operating pressure of the motor or an airflow rate through the motor;   performing a determination process to determine, based on the first value of the operating parameter of the motor and a first pre-determined relationship between values of the operating parameter of the motor and values of an inlet restriction of the air-moving device, a value of the inlet restriction of the air-moving device; and   controlling, based on the determined value of the inlet restriction, the input power of the motor.   
     
     
         2 . The method of  claim 1 , wherein the operating parameter is the operating pressure and the measurement process comprises determining the first value of the operating parameter of the motor based on:
 an ambient pressure measurement; and   a motor-inlet pressure measurement during operation of the motor.   
     
     
         3 . The method of  claim 2 , wherein the ambient pressure measurement and the motor-inlet pressure measurement are measured at different times by a single pressure sensor. 
     
     
         4 . The method of  claim 1 , wherein the measurement process comprises determining the first value of the operating parameter of the motor based on:
 a first pressure measurement of a pressure at a first position in a motor assembly in which the motor is located; and   a second pressure measurement of a pressure at a second position in the motor assembly;   wherein the second position is downstream of the first position.   
     
     
         5 . The method of  claim 1 , wherein the first pre-determined relationship relates values of the operating parameter of the motor and values of one or more further parameters to values of the inlet restriction of the air-moving device, and wherein the determination process comprises:
 determining the value of the inlet restriction based on one or more respective further parameter values of the one or more parameters.   
     
     
         6 . The method of  claim 5 , wherein the one or more further parameters comprise one or more of:
 an ambient pressure;   an ambient temperature;   a motor input power; and   a build tolerance of the air-moving device.   
     
     
         7 . The method of  claim 5 , wherein the determination process comprises:
 determining a first normalised value of the operating parameter by normalising the first value of the operating parameter by use of one or more respective values of the one or more further parameters; and   determining the value of the inlet restriction of the air-moving device based on the normalised operating parameter.   
     
     
         8 . The method of  claim 5 , wherein the one or more further parameters comprise a value of a filter loading of a filter of the air-moving device. 
     
     
         9 . The method of  claim 8 , wherein the determination process comprises determining the value of the filter loading. 
     
     
         10 . The method of  claim 9 , wherein the determining the value of the filter loading comprises:
 performing a second measurement process comprising determining a first value of a second operating parameter of the air-moving device, the first value being a value of the second operating parameter when the air-moving device is operating with a first inlet restriction condition; and   performing a second determination process to determine the value of the filter loading, the determination process comprising determining, based on the first value of the second operating parameter and a second pre-determined relationship relating, for the air-moving device when operating with the first inlet restriction condition, values of the second operating parameter to values of the filter loading, the value of the filter loading.   
     
     
         11 . The method of  claim 10 , wherein the second operating parameter is:
 the operating pressure of the motor of the air-moving device;   a speed of the motor of the air-moving device; or   an airflow rate through the motor of the air-moving device.   
     
     
         12 . The method of  claim 10 , wherein the determining the first value of the second operating parameter comprises:
 determining a plurality of values of the second operating parameter;   determining a distribution of the plurality of values of the second operating parameter;   determining a first property of the distribution; and   determining, based on the first property of the distribution, the first value of the second operating parameter.   
     
     
         13 . The method of  claim 12 , wherein the first property of the distribution is a minimum value in the distribution. 
     
     
         14 . The method of  claim 1 , wherein the controlling comprises adjusting the motor input power according to a set profile relating motor input power values to inlet restriction values. 
     
     
         15 . The method of  claim 14 , wherein the set profile is a continuous profile. 
     
     
         16 . The method of  claim 14 , wherein the set profile comprises a plurality of discrete power levels, each of the power levels corresponding to a respective range of values of inlet restriction. 
     
     
         17 . The method of  claim 1 , comprising, during operation of the air-moving device, performing the measurement process, the determination process and the controlling a plurality of times. 
     
     
         18 . A set of machine-readable instructions which when executed by a processor of an air-moving device cause the air-moving device to perform the method according to  claim 1 . 
     
     
         19 . An air-moving device comprising:
 a processor; and   a storage comprising a set of machine-readable instructions which when executed by the processor cause the processor to perform the method according to  claim 1 .   
     
     
         20 . The air-moving device of  claim 19 , wherein the air-moving device is a vacuum cleaner.