METHOD OF CONSTANT RPM CONTROL FOR A VENTILATION SYSTEM
First Claim
1. A method of operating an electric motor in a ventilation system, the method comprising:
- providing a blower comprising a motor and a fan coupled to the motor, the blower being configured to generate an airflow in a ventilation duct;
monitoring a rotational speed of the motor;
monitoring an electric current applied to a motor; and
controlling the motor'"'"'s operation so as to maintain the rotational speed within proximity of a target rotational speed while the electric current is smaller than a reference value.
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0 Petitions
Accused Products
Abstract
A method of constant airflow control for a ventilation system is disclosed. The method includes various controls to accomplish a substantially constant airflow rate over a significant change of the static pressure in a ventilation duct. One control is a constant I·RPM control, which is primarily used in a low static pressure range. Another control is a constant RPM control, which is primarily used in a high static pressure range. These controls requires neither a static pressure sensor nor an airflow rate sensor to accomplish substantially constant airflow rate while static pressure changes. This is because these controls use only intrinsic control variables which are electric current and rotational speed of the motor. Also, the method improves the accuracy of the control by correcting certain deviations that are caused by the motor'"'"'s current-RPM characteristics. To compensate the deviation, the method adopts a test operation in a minimum static pressure condition. Also disclosed is an apparatus for conducting these control methods.
126 Citations
21 Claims
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1. A method of operating an electric motor in a ventilation system, the method comprising:
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providing a blower comprising a motor and a fan coupled to the motor, the blower being configured to generate an airflow in a ventilation duct; monitoring a rotational speed of the motor; monitoring an electric current applied to a motor; and controlling the motor'"'"'s operation so as to maintain the rotational speed within proximity of a target rotational speed while the electric current is smaller than a reference value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. A method of operating an electric motor in a ventilation system, the method comprising:
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providing a blower comprising a motor and a fan coupled to the motor, the blower being configured to generate an airflow in a ventilation duct; detecting an electric current applied to the motor; detecting a rotational speed of the motor; and controlling the motor'"'"'s operation so as to generate the airflow with a substantially constant airflow while a static pressure within the duct substantially changes, wherein controlling the motor'"'"'s operation does not use an input of an airflow rate generated by the blower. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21)
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Specification