Abstract: A method for measuring an air volume of a blower motor, including: a) establishing M constant air volume control functions Qi=F(n) corresponding to M air volume points CFMi in a microprocessor of a motor controller; b) starting the motor, measuring a real-time rotational speed n0 and a parameter Q0 of the motor after the motor runs in a stable state, putting the parameter Q0 into the functions Qi=F(n) to obtain multiple rotational speeds ni, comparing the real-time rotational speed n0 with the multiple rotational speeds ni corresponding to the multiple air volume points CFMi, and determining a real-time detected air volume CFM0 which falls within two air volumes CFMi and CFMi-1; and c) calculating the real-time detected air volume CFM0 according to the two air volumes CFMi and CFMi-1 and the rotational speeds ni and ni-1 using an interpolation method.

Abstract: A daughter circuit board of an electronically commutated motor. The daughter circuit board has the function of interface signal conversion and can be plugged into a mother circuit board of a motor controller to match with an interface signal of a user end control system. The daughter circuit board includes an interface unit circuit. The interface unit circuit includes an RS485 interface circuit. The interface unit circuit is integrated on the daughter circuit board.

Abstract: A daughter circuit board of a brushless DC motor for interface signal conversion, having circuit units integrated on the daughter circuit and eight ports for communicating with a control system of a user terminal. The daughter circuit board is plugged into a motor controller for signal conversion so that the motor controller communicates with the control system of the user terminal. The eight ports include a signal input port of analog control, a signal port for activating a fan mode, signal ports of speed feedback, a reserved signal port, a port of COM, a port of DC power supply, and a R/T port.

Abstract: A method for controlling air volume including: 1) establishing a functional relation formula for air volume in a microprocessor control unit of a motor controller; 2) inputting a target air volume into the microprocessor control unit; 3) starting a motor by the motor controller to enable the motor to achieve a rotational speed and fall on a steady state; 4) recording the torque and rotational speed in the steady state, and calculating an air volume in the steady state; 5) comparing the target air volume with the calculated air volume; 6) re-recording a steady torque after the motor falls on a new steady state under an increased or reduced rotational speed, and recalculating the air volume in the new steady state; and 7) repeating steps 5) and 6) to adjust the rotational speed until the calculated air volume is equal or equivalent to the target air volume.

Abstract: A method for controlling air volume including: 1) establishing a functional relation formula for air volume in a microprocessor control unit of a motor controller; 2) inputting a target air volume into the microprocessor control unit of the motor controller; 3) starting a motor by the motor controller under a torque to enable the motor to fall on a steady state; 4) recording the rotational speed in the steady state, and calculating an air volume in the steady state; 5) comparing the target air volume with the calculated air volume; 6) re-recording a steady rotational speed after the motor falls on a new steady state under an increased or reduced torque, and recalculating the air volume in the new steady state; and 7) repeating steps 5) and 6) to adjust the torque until the calculated air volume is equal or equivalent to the target air volume.

Abstract: A daughter circuit board of a brushless DC motor for interface signal conversion, having circuit units integrated on the daughter circuit and eight ports for communicating with a control system of a user terminal. The daughter circuit board is plugged into a motor controller for signal conversion so that the motor controller communicates with the control system of the user terminal. The eight ports include a signal input port of analog control, a signal port for activating a fan mode, signal ports of speed feedback, a reserved signal port, a port of COM, a port of DC power supply, and a R/T port.