[Inductor-Recorded Traction Motor Sound モハラジオ録音] 700-7000 Series Shinkansen

#モハラジオ #TractionMotorPWMSound #700Series

00:00 Title & Introduction
00:05 File 1-1: Type 1 Acceleration
02:56 File 1-2: Type 1 Braking
05:22 File 2-1: Type 2 Acceleration
09:11 File 2-2: Type 2 Braking
11:35 Manufacturer Presumption

Car Type: JR West 700-7000 Series Shinkansen
VVVF: Mitsubishi/Toshiba? 3-level IGBT-VVVF

Pattern (Type 1):
Asynchronous (Dipolar Modulation → Unipolar Modulation) → Multi-Pulse Mode → 1P
Asynchronous Mode Carrier Frequency:
500Hz (Dipolar Modulation) → 1000Hz → (Continuous Transition) → 1200Hz (Unipolar Modulation)
For the dipolar modulation, the most emphasized component is around twice the carrier frequency.

Pattern (Type 2):
Asynchronous (Dipolar Modulation → Unipolar Modulation) → Multi-Pulse Mode → 1P
Asynchronous Mode Carrier Frequency:
500Hz (Dipolar Modulation) → 1000Hz (Unipolar Modulation)
For the dipolar modulation, the most emphasized component is around four times the carrier frequency.

Sound Characteristics:
Please refer to the "Manufacturer Presumption" section of the video.

Others:
The following website summarizes the distribution of the two types of sounds:
http://iamreck.g2.xrea.com/tec700e/sh...
(Red = Type 1, Green = Type 2)
In addition, although it is from the C sets which have already been retired (the traction system is different from the B/E sets), there is a description of the pulse mode of Fuji Electric VVVF in the PDF below, as "Asynchronous → 15P → 9P → 3P → 1P".
https://www.fujielectric.co.jp/compan...
This may be the reason why the sound of C sets' cars that are thought to be equipped with this Fuji Electric's VVVF is different from the Type 2 in this video, especially for the time when shifting to synchronous modulation during acceleration.

The sound sources for the other cars in this video can be found below.

・Meitetsu 3100 Series (Toshiba Traction)
http://vvvfdatabase.starfree.jp/vvvf_...

・JR East E2-1000 Series
   • [Inductor-Recorded Traction Motor Sou...  

・Sapporo Municipal Subway 5000 Series (Mitsubishi Traction)
http://vvvfdatabase.starfree.jp/vvvf_...

・JR Kyushu 800 Series Shinkansen
   • [Inductor-Recorded Traction Motor Sou...  

・Additional data
① 700-7000 series (Type 1) with frequent chattering during braking
② EH200 series departure recorded from outside the car (on the platform)
https://x.com/VVVF_tokyu2000/status/1...

The AC traction PWM sound shown in this video is recorded by a sensor. This sensor is made by myself just using a 100mH inductor.
Regarding the files used, the extra noise components has been reduced from the ones saved immediately after recording.
Due to the resolution of the spectrogram software, the frequency displayed in this video may include some error. Thank you for your understanding.
These sounds are recorded in 2022 - 2023.
Sorry, I am NOT taking requests for recordings.

Posted by Ebara Express
Twitter (Available in Japanese; translate please!)
  / vvvf_tokyu2000  

Website "VVVF Database" (Available in Japanese; translate please!)
http://vvvfdatabase.starfree.jp

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