CLAIM OF PRIORITY

This application claims the priority based on the Japanese Patent Application No. 2018-238310 filed on Dec. 20, 2018. The entire contents of which are incorporated herein by reference for all purpose.

BACKGROUND

Technical Field

The present invention relates to a power conversion device and a high-voltage noise filter.

Related Art

In an electric vehicle, a plug-in hybrid vehicle, and the like, a higher voltage is progressively employed in a power drive battery for the purpose of improving charging efficiency. Additionally, in an electric vehicles or the like, DC current output from the power drive battery is converted to AC current by a power conversion device (inverter) and then supplied to a three-phase motor so as to drive the three-phase motor with the AC current to rotate tires.

In a power conversion device, it is known that an electromagnetic noise is generated during power conversion, adversely affects another electronic circuit mounted on an electric vehicle or the like, and causes malfunction and the like. Additionally, it is also known that the electromagnetic noise generated from the power conversion device is increased along with: increase in a voltage of the input DC current; and increase in a frequency of the output AC current.

Considering such situations, conventionally, a high-voltage noise filter is provided in the power conversion device in order to suppress the generated electromagnetic noise from being propagated to the outside of the power conversion device via a cable and the like. The high-voltage noise filter includes: a magnetic core functioning as an inductor (L) constituting an LC filter; and a capacitor (C).

Incidentally, the magnetic core included in the high-voltage noise filter generates heat due to the generated electromagnetic noise, and a heat generation amount is increased along with increase in the electromagnetic noise. Therefore, in the case where a voltage of the power drive battery is increased, a measure to dissipate the heat is required because the increase of the electromagnetic noise causes increase in the heat generation amount of the magnetic core. Additionally, a measure to suppress the increased electromagnetic noise is also required.

Regarding a heat dissipation structure in the power conversion device, WO 2015/133201 A discloses a structure in which a cooling medium is circulated in an entire housing of the power conversion device.

SUMMARY

As an exemplary measure to dissipate heat from a magnetic core, a method of providing a heat sink in the magnetic core is conceivable.

Also, as an exemplary measure to suppress an electromagnetic noise, a method of increasing capacitance of a capacitor constituting an LC filter is conceivable.

However, in the case of providing the heat sink in the magnetic core and further increasing the capacitance of the capacitor, an entire size of a high-voltage noise filter is increased and the weight is also increased. Such situations are not preferable in consideration of in-vehicle use.

The present invention is made in view of the above-described situations, and an object of the present invention is to achieve both heat dissipation from a magnetic core and improvement in a suppression effect of an electromagnetic noise.

The present application includes a plurality of means to solve at least a part of the above-described problems, and an example thereof is as follows. To solve the above-described problems, a power conversion device according to an aspect of the present invention includes: a power module that converts DC current to AC current; and a high-voltage noise filter that suppresses an electromagnetic noise generated from the power module. The high-voltage noise filter includes: a metal housing that is grounded; an anode bus bar connecting an anode of a power source of the DC current and an anode of the power module; a cathode bus bar connecting a cathode of the power source and a cathode of the power module; a first magnetic core formed in an annular shape and having a through hole where the anode bus bar and the cathode bus bar are made to pass through; an X capacitor having one end connected to the anode bus bar and having the other end connected to the cathode bus bar; a first Y capacitor having one end connected to the anode bus bar and having the other end grounded; a second Y capacitor having one end connected to the cathode bus bar and having the other end grounded; and a first cooling unit connected to the first magnetic core and the metal housing. A part of the anode bus bar is arranged in a manner facing the first cooling unit, and a part of the cathode bus bar is arranged in a manner facing the first cooling unit.

According to the present invention, it is possible to achieve both heat dissipation from the magnetic core and improvement in a suppression effect of an electromagnetic noise.

Problems, configurations, and advantageous effects other than those described above will be clarified by the following description of embodiments.

