[Inductor-Recorded Traction Motor Sound モハラジオ録音] Keikyu N1000 Series [Siemens GTO-VVVF]

#モハラジオ #TractionMotorPWMSound #Keikyu
Car Type: Keiyu N1000 Series (1033 Set)
Traction: Siemens 2-Level GTO-VVVF
PWM Pattern:
Asynchronous (90 Hz → 100 Hz → … → 400 Hz) → Advanced PWM (Several steps. I used the word "Multi-Pulse Mode(s)" for them in this video.) → 1P
(Details are described in this video.)
Sound Characteristics:
As it is called "Do-Re-Mi-Fa Inverter" or "Singing Train", the most distinctive feature is the asynchronous modulation part that sounds like playing the scale when the train is accelerating from 0 km/h. If you listen to it normally at the station or in a car, you might recognize the sound of "(E♭)-F-G-A-B-C-D-E♭-F-G" ((156 Hz)-175 Hz-...-400 Hz), but in fact, it is further preceded by "F♯-G-C-D" (90 Hz-100 Hz-131 Hz-147 Hz). However, they are almost unrecognizable in stations and cars because of their low volume or short duration.
For synchronous modulation, advanced PWM (not the simple sinusoidal PWM) is used in several stages.
For this part, I've described the pulse modes with reference to this video by yuqquu, who did the analysis of them.
• ドレミファインバーター(京急1000形・E5...
Depending on the way of acceleration and braking, the pattern of synchronous modulations seems to vary, but in this first video I will show only the usual patterns of them.
(If you want to check those patterns, please watch this second video.)
• [モハラジオ録音]【加減速パターン集】 京急...
The third file shows the "scale" part not rising ideally.I think you can sometimes recognize this even if you listen to it normally. Also, at this time, it was accelerating to nearly 110-120 km/h at once.
Since the car has an aluminum body, such a sound could not be picked up on the floor above the motor, so it was recorded at the door rail of the passengers' doorway behind the driver's cab of Car 1033 and Car 1040. (Shown in the last photo. It has become difficult to pick up this sound at the same position of Car 1040 from the latter half of 2020, probably because of the car repair.)
Although the noise component is also large, the modulation spectrum can be visualized relatively clearly.
The AC traction PWM sound shown in this video is recorded by a sensor which is placed on the floor of a train car. This sensor is made by myself just using a 100mH inductor.
Due to the resolution of the spectrogram software, the frequency displayed in this video may include some error. Thank you for your understanding.
This sound is recorded in June and October 2020. The 1033 Set, which was the last one that had this sound, unfortunately finished operation with Siemens traction in July 2021, and was later refurbished. Therefore, this sound cannot be heard now.
Sorry, I am NOT taking requests for recordings.
Posted by Ebara Express
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vvvfdatabase.st...
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Thanks to: yuqquu
/ yuqquu