BLDC voltage and motion equations

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Variable description:

R	Internal Resistance
I	Phase Current
U	Bus voltage
	Power tube pressure drop
	Back-to-Force
	Back-EMR Coefficient
N	Motor Speed (RPM)
	Electric torque (Nm)
	Load torque (Nm)
	Flywheel moment (another method of moment of inertia J ,)

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BLDC MotorDynamicFeature equation:

???????????????????????????? (1)

???????????????????????????????? (2)

???????????????????????????????? (3)

???????????????????????????? (4)

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The BLDC motor is obtained from formula (1)-(3 ).Stable OperationMechanical Characteristic Equation

???????????????????????????? (5)

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Derived from formula (1)-(4:

Lath Transformation:

Obtain the BLDC transfer function:

???????????????? (6)

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Ling

EMR transfer coefficient:

Torque transfer coefficient:

Electromagnetic time constant:

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The motor speed equation is obtained:

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Dynamic Structure of BLDC Motor