New energy electric vehicle power system scheme 15kw-144-312V (DC) motor

1. Motor appearance and structure

 

2. Motor technical parameters

project		Specification	Executive standard
	type	Permanent Magnet Synchronous Motor	GB/T18488.1-2015              Motors and Controllers for Electric Vehicles Part 1 Specifications         GB/T18488.2-2015 Electric Motors and Controllers for Electric Vehicles Part 2 Test Methods
	three-phase connection	Y type
	rated power	15KW
	Rated speed	3000r / min
	Rated torque	47N.M
	peak power	35KW
	peak speed	6600r / min
	peak torque	150N.M
	Working temperature	-25℃~40℃
	storage temperature	-40℃~85℃
	quality	35kg±2
	Insulation class	H
	cooling method	Free cooling

3. Motor technical description

1. Motor installation method: This motor is a pure electric system drive motor. The drawings and the shape and structure of the motor are batch products of our company and are for reference only (the dimensions of the motor body and shaft extension)

2. Motor outlet method:

    a. Three-phase power line: use a junction box, and lead the line out through a waterproof cable lock   

    b. Sensor port: The sensor port adopts Amphenol waterproof connector ;

3. Magnetic material: high temperature permanent magnet

4. The bearing adopts imported high protection grade products

5. Cooling method: natural cooling

6. The rotor position sensor is a resolver

7. Built-in stator temperature sensor: PT100

8. Motor installation size: 285 × 223 ( excluding shaft extension and junction box)

4. Motor analysis report

Rated voltage	144VDC	peak current	400A
rated power	15KW	peak power	35KW
Rated speed	3000rpm	peak speed	6600rpm
Rated torque	47Nm	peak torque	150 Nm

1 . Technical indicators

2. Finite element simulation

1 ) Peak torque simulation

Simulation conditions:

Speed: 2300 RPM   Stator OD: 180   Number of Poles: 8

Coercivity: 870KA/M

According to the above simulation conditions, the results of various parameters are given:

 

1 ) -1 torque curve

1 ) -2 wire back EMF curve

 

1) -3 Back EMF Fourier decomposition

 

Peak torque simulation conclusion

According to the above analysis conclusion:

When the loading current is 400A , the peak torque of the motor is 162.5 Nm , and the peak power is 39.1KW . At this time, the peak value of the winding back EMF line voltage does not exceed 113V.

The motor meets peak power and peak torque requirements.

2) Peak speed simulation

Simulation conditions:

Speed: 6600 RPM   Stator OD: 180 Number of Poles: 8

Coercivity: 870KA/M

According to the above simulation conditions, the results of various parameters of the quadrature axis current at 80A are given:

 

2 ) --1 torque curve

2)-2 line back EMF curve

 

2)  -3 Back EMF Fourier decomposition

 

Peak speed simulation conclusion

According to the above analysis conclusion:

When the current is loaded at 300A and the quadrature axis current is 80A , the torque is 57Nm . At this time, the peak value of the winding back-EMF line voltage is 112.5V , and the motor power is: 6.28 × 57 × 6600/60=39.4KW,

Meet the requirements of constant power expansion range.

3) No-load rated speed simulation

Simulation conditions:

Speed: 3000 RPM   Stator Outer Diameter: 180 Number of Poles: 8    Coercive Force: 970KA/M

According to the above simulation conditions, the results of various parameters are given:

3 ) 1 Magnetic field line analysis

 

3 ) -2 magnetic density distribution

 

3 ) -3 cogging torque curve

 

4) No-load peak speed simulation

Simulation conditions:

Speed: 6600 RPM   Stator Outer Diameter: 180 Number of Poles: 8    Coercive Force: 970KA/M

According to the above simulation conditions, the results of various parameters are given:

 

4 ) -1 cogging torque

4 ) -2 winding back EMF curve

 

4 ) -3 Back EMF Fourier decomposition

The maximum value of the back EMF line voltage is 192.3V . Considering the parameters of the magnetic steel performance at 20 degrees in the simulation, the back EMF is about 185V in actual operation, and a MOS with a withstand voltage of 200V can be used, and the cost of the controller will be greatly reduced.

 

3. Rotor stress simulation

Simulation conditions:  1.2 times the peak speed

 

Simulation model

 

centrifugal stress

Safety factor

 

From the above analysis, it can be seen that at 1.2 times the peak speed of the motor, the stress at the magnetic isolation bridge is the largest, which is only 34.7Mpa, and the safety factor is large, so it can run safely.

Measured rated curve

 

Rated electric characteristic curve conforms to simulation and theoretical design

actual data

 

Measured rated data collection.

actual data

 

Measured rated data collection.

Feeding characteristic curve

 

efficiency map

 

More than 80% of the high-efficiency area accounts for 82% , and the highest efficiency is 94.5% . The distribution of the high-efficiency area is in line with the ideal operating conditions of electric vehicles

Motor temperature rise curve

 

The measured temperature rise curve of the motor, the air temperature is 25 degrees, the full load still air flow test temperature is up to 105 degrees, and the actual temperature rise is 70K , which is well adapted to the vehicle operating environment

High-speed temperature rise data

 

The measured high-speed temperature rise data of the motor is suitable for running at the highest speed of the vehicle

Motor compatible models