Patent MX-351653-B (MX)
Title: Constant torque control method for ecm motor.
Inventor: YONG ZHAO
IPC: H02P6/18
Filed: 2013-11-08
Abstract: A constant torque control method for an ECM motor comprises the following steps: step A) the value of a target torque T0 from external inputs is obtained; if the motor is in a stopped state, the motor is started, and a microprocessor acquires the original value of the chopped output voltage P of a PWM signal; if the motor is in a running state, the microprocessor acquires the current value of the chopped output voltage P of the PWM signal; step B) the microprocessor calculates the value of the corresponding target bus current Itad by using the function Itad= F(T, P) on the basis of the values of the target torque T0 and the chopped output voltage P of the PWM signal, detects the real-time bus current Ibus; step C) the microprocessor compares the value of the target bus current Itad with the value of the real-time bus current Ibus on the basis of the detected real-time bus current Ibus, and performs closed-loop control. The mathematical model of the constant torque control method is simple, the algorithm is concise, the calculation requirement for CPU is low, the cost is low and the control precision is high. A constant torque control method for an ECM motor comprises the following steps: step A) the value of a target torque T0 from external inputs is obtained; if the motor is in a stopped state, the motor is started, and a microprocessor acquires the original value of the chopped output voltage P of a PWM signal; if the motor is in a running state, the microprocessor acquires the current value of the chopped output voltage P of the PWM signal; step B) the microprocessor calculates the value of the corresponding target bus current Itad by using the function Itad= F(T, P) on the basis of the values of the target torque T0 and the chopped output voltage P of the PWM signal, detects the real-time bus current Ibus; step C) the microprocessor compares the value of the target bus current Itad with the value of the real-time bus current Ibus on the basis of the detected real-time bus current Ibus, and performs closed-loop control. The mathematical model of the constant torque control method is simple, the algorithm is concise, the calculation requirement for CPU is low, the cost is low and the control precision is high. A heat-conducting apparatus, a backlight module, and a liquid crystal display. The heat-conducting apparatus (3) comprises: collecting frames (31) and conductive plates (32) that are perpendicularly connected with each other. The collecting frames (31) are used for surrounding LEDs (2) and for being tightly affixed with a mount surface (10) of a circuit board (1). The conductive plates (32) are used for being tightly affixed with a back panel. The backlight module comprises the heat-conducting apparatus (3). The liquid crystal display comprises the backlight module. No effective thermal pathway defect is present between the circuit board (1) and the back panel. By arrangement of the heat-conducting apparatus (3), heat accumulated on the circuit board is conducted rapidly and in large amounts to the back panel for heat dissipation, thus increasing heat conducting efficiency and cooling effects.