5 results about "Differential mode noise" patented technology

This utility model discloses a frequency converter controller, including a control unit, a first filtering topology, and a second filtering topology. The first filtering topology includes a differential-mode inductor unit, and the second filtering topology includes a common-mode inductor unit. The first filtering topology is connected to the live wire, neutral wire, and protective ground wire, and receives the input signal from the power input terminal, suppresses the differential-mode noise and common-mode noise of the input signal from the power input terminal, and generates a first electrical signal. The second filtering topology receives the first electrical signal, suppresses the differential-mode noise and common-mode noise of the first electrical signal, and generates a second electrical signal. The control unit receives the second electrical signal. Because a differential-mode inductor unit is added to the first filtering topology, the number of magnetic rings can be reduced, the number of installation steps can be reduced, and costs can be optimized.

This application provides an AC switching power supply. In this AC switching power supply, the input terminal of each inverter bridge arm is connected to the output terminal of a DC switching power supply; each output terminal of the AC switching power supply is connected to the output terminal of the corresponding inverter bridge arm. In this application, since the common-mode noise of at least two DC switching power supplies cancels each other out, the common-mode noise of the AC switching power supply is suppressed. Furthermore, since in the prior art, the drive signal frequencies of each DC switching power supply in the AC switching power supply are the same, i.e., the number of noise sources at the same frequency point is equal to the number of DC switching power supplies, when the number of DC switching power supplies is the same, the noise sources of this AC switching power supply at the same frequency point will not exceed those in the prior art. Therefore, the differential-mode noise of this AC switching power supply can at least remain unchanged. In summary, the AC switching power supply provided in this application suppresses its own EMI.

The utility model discloses a kind of multi-stage filtering integrated module of composite structure, electric drive system and vehicle, belong to new energy electric car electric drive technical field, multi-stage filtering integrated module of composite structure includes upper cover fastener, lower fastener, capacitor filter module, magnetic filter module, bus copper bar, external copper bar, connecting copper column;The magnetic ring is sleeved in the outer circumferential surface of copper bar along copper bar extension direction;Capacitor filter module includes PCB board and the capacitor welded on PCB board, capacitor filter module is crimped with bus copper bar by connecting copper column, another grounding hole is additionally provided on PCB board, ensure that the Y capacitor of connecting bus copper bar and ground can have good electrical contact with metal shell;The multi-stage filtering integrated module of composite structure can guarantee its effective suppression new energy electric car's common mode and differential mode noise in electric drive, while guarantee the simplicity of assembly and the stability of fastening, filtering integrated module meets national standard, with the characteristics of better electrical and structural stability.

The application belongs to the technical field of power electronics, and relates to a CM-DM integrated active EMI filter with adjustable common-mode and differential-mode attenuation, comprising: a first noise attenuation circuit and a second noise attenuation circuit; the first noise attenuation circuit and the second noise attenuation circuit are both composed of a detection link, an amplification link and an injection link; the application takes a negative bus as a reference, two operational amplifiers use the same power supply system, and common-mode and differential-mode noises can be simultaneously and effectively attenuated through constructing a proper compensation current path, and common-mode and differential-mode insertion losses can be respectively changed by changing the gains of the first and second noise attenuation circuits; therefore, the application realizes the separate adjustment of common-mode and differential-mode noise attenuation capabilities.

The utility model discloses a kind of multi-stage filtering integrated devices, electric drive system and vehicle, belong to new energy electric car electric drive technical field, multi-stage filtering integrated devices include structural member, multiple magnetic elements, multi-stage capacitor filter unit and copper bar;The copper bar is fixed on structural member, and copper bar end is used for connecting load by lead through magnetic element, other magnetic element is set on copper bar and is connected with structural member;Multi-stage capacitor filter unit is interval arranged along the arrangement direction of copper bar, and capacitor filter unit includes PCB board, and capacitor is set on it, PCB board is across set on the top of copper bar, grounding point of PCB board is embedded with ground terminal, and the pin of capacitor is respectively connected with copper bar and ground terminal of PCB board;The multi-stage filtering integrated device can effectively suppress common mode and differential mode noise of electric drive in new energy electric car, filtering performance meets international standard, and has the characteristics of strong electrical stability and strong structure.