00:00High Efficiency in Everyday Driving
00:05Instantaneous High Power when Accelerating
00:08That's the kind of EV we dream of
00:11Made possible by the balance of power, efficiency and lasting performance
00:17A challenge no one solved
00:19Until Hyundai Motor Group did with their new Motor Drive System
00:22Let's take a closer look
00:24Sure, sounds great
00:26Electric vehicles don't just move with a motor alone
00:29The Motor Drive System consists of three key parts
00:32The motor, reducer and inverter
00:35The motor generates torque
00:38The reducer transfers that torquer to the wheels
00:41And the inverter, the conductor of the system
00:44Converts the battery's DC power into AC power for the motor
00:48Precisely controlling how and when that power is used
00:51How does it control power exactly?
00:54The inverter consists of semiconductor-based switches
00:57When the switches are closed, current flows
01:00When they're open, it doesn't
01:03Depending on the rhythm and pattern of the switches
01:07The motor rotates and moves the vehicle forward
01:10When AC current flows through the motor's coils
01:14It creates a magnetic field that constantly changes as the current alternates
01:19This shifting magnetic field pushes and pulls the magnetized rotor at the motor's center
01:24Causing it to spin
01:26Wow, so that's how an EV moves
01:29Now, let's talk about power
01:32The power output is determined by voltage and current
01:35To increase the drive motor's power
01:38You can increase the battery voltage or adjust the motor's characteristics to increase current
01:43Usually, it's the latter
01:45But increasing current makes the motor drive system larger and heavier
01:50And heat management becomes more difficult
01:53Also, when designed mainly for high power output
01:57Efficiency drops significantly during everyday city driving
02:01So, how are these limitations solved?
02:05That's where the inverter plays a crucial role
02:07While it doesn't increase battery voltage itself
02:10The way it applies and controls that voltage greatly affects the power
02:14And, we developed an innovative system that expands this usable voltage range
02:21By increasing voltage utilization
02:23Conventional inverters use six switches
02:27Often employing silicon carbide semiconductors
02:30A high-efficiency but costly material
02:33We added six silicon switches
02:36Creating a total of 12 switches in our new system
02:39As a result, the voltage that can be applied to the motor increased by about 70%
02:45How exactly was the voltage range expanded?
02:48By doubling the number of inverter switches connected to a single motor
02:52We were able to apply higher voltage levels
02:54In regular driving, only the silicon carbide switch set is used to maintain high efficiency
03:00In high-speed or high-output power conditions, both switch sets operate together
03:05Is doubling the number of switches really that significant?
03:09It's more than just adding parts
03:11It's a fundamental transformation of the entire control system architecture
03:15When more switches are added, a completely new level of coordination between them becomes necessary
03:21Like two riders on a tandem bicycle who must pedal in perfect sync to move forward
03:27A conventional six-switch inverter divides them into upper and lower sets for three phases
03:32Operating in eight different combinations under strict switching rules
03:37So, what happens when the number of switches doubles?
03:39The combinations increase eightfold, requiring much more precise control
03:44To move precisely, the key must be how the flow of electricity is controlled, right?
03:49Exactly! If you visualize the six-switch combinations as a hexagonal voltage space vector
03:55The maximum voltage that can be applied to the motor equals one side of that hexagon
04:00Now imagine moving a voltage vector along that line
04:04If it moves in steps, how would the car feel?
04:07Uh, like it's jerking or stuttering
04:10Right! That's why advanced control to smooth the voltage vectors is so important
04:16While six-switch control is common, Hyundai Motor Group devised a system that controls
04:2212 switches simultaneously, expanding the usable voltage space
04:27One module fixes six switches in a six-step configuration, while the other controls the remaining six through 64 possible combinations
04:36To manage these two voltage spaces flexibly, Hyundai Motor Group introduced a transfer switch
04:42that shifts to the optimal state depending on driving conditions
04:46So, the car can respond freely depending on the situation?
04:50Precisely! The transfer switch's precise control allows smooth mode transitions, providing
04:57strong power during acceleration and high efficiency during regular and long-distance driving
05:03Saying the whole system was rebuilt from scratch wasn't an exaggeration
05:07It's not just about increasing numbers
05:09It's about orchestrating 12 switches to operate as one through an advanced control strategy
05:15But with all this complexity, doesn't the system get bigger or heavier?
05:19Normally yes, but we solved the size and weight issue with our own in-house designed power modules
05:25The inverter's size depends on its built-in semiconductor power modules
05:30By integrating nine modules into three, we created a simpler structure
05:34And improved cooling from single-sided to double-sided
05:40Thanks to these step-by-step optimizations, we achieved a high-performance yet compact inverter design
05:47Wow! I didn't realize EV motor systems were this advanced!
05:51This is only the beginning
05:54The technology will expand to more vehicle types and soon it will be on roads everywhere
06:00As EVs become part of everyday life, Hyundai Motor Group continues to shape the standards of tomorrow
06:07Hello!
06:16For more videos – check the rule
06:19For more videos – check the rule
06:20Untertitelung des ZDF, 2020
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