three phase rectifier voltage issue

[alal]

I captured an output voltage waveform of the three-phase rectifier system. Could anyone help me understand what might be the cause of the little spikes?

 

[Minder]

Is this supplying any load, or just a 3ph rectifier?
What is the source of the 3ph?
Where are you referencing it to, the wave form is not a normal rectified pattern for 3phase.
The should have a 120deg overlap for every cycle.
M.

 

[alal]

Is this supplying any load, or just a 3ph rectifier?
What is the source of the 3ph?
M.

It has dc crane and dc led lights on the system. The crane load is on and off. When the led lights are on, the problem exaggerates. I'm trying to figure out the source of the problem, the rectifier or the led driver. The source of the 3ph is from a three-phase ac transformer.

 

[Minder]

I added a edit in the mean time, as I said the wave form does not look normal other than the spike.
M.

 

[Minder]

It appears to be more 1phase than a typical 3 phase output.
M.

 

[alal]

It appears to be more 1phase than a typical 3 phase output.
M.

I think the correct waveform should look like this. It seems it's missing every other peak.

 

[Minder]

You should be getting a 360deg approx 5% ripple sitting on the top.
What is the nature of the rectifier and where is your reference point from?
M.

 

[alal]

You should be getting a 360deg approx 5% ripple sitting on the top.
What is the nature of the rectifier and where is your reference point from?
M.

The time division is 7.95 on the x-axis. I counted the peaks based on this time.

 

[Alec_t]

Are you sure the polarities of all the rectifier diodes are correct?

 

[alal]

Are you sure the polarities of all the rectifier diodes are correct?

I think the polarities are correct. I run a simulation with the wrong polarity, the waveform does not look like the measured.

 

[alal]

I found out it is actually half controlled rectifier, so 3 diodes, 3 SCRs. The waveform is normal.