TERMINAL FOR A POWER ELECTRONIC COMPONENT AND POWER ELECTRONIC COMPONENT

The present invention concerns a terminal for a power

electronic component and a power electronic component

comprising the terminal.

A terminal is configured to provide an electrical connection of a power electronic component to external circuits, for example by connecting a cable to the power electronic

component. During the assembly of the cable to the terminal, splashing of the cable may occur. In particular, fine- stranded cables and stranded cables may suffer from splashing when they are assembled to a terminal. Splashing of a cable reduces the creepage distance between adjacent terminals or between a terminal and a metal housing. A reduction in the creepage distance increases the risk of a voltage flashover. Moreover, splashing can also reduce a contact area of the cable to a busbar of the terminal, thereby reducing the quality of the electrical contact. Therefore, it is an object of the present invention to provide an improved terminal, for example, a terminal which is designed such that a cable that is connected to the terminal will not suffer from splashing.

This object is solved by the terminal according to claim 1.

A terminal for a power electronic component is provided which comprises a housing and a fixation element. The housing comprises an opening and the fixation element comprises a window. The fixation element is movable to an insertion state and to a fixing state, wherein the window of the fixation element is aligned with the opening of the housing in the insertion state of the fixation element.

The window of the fixation element may be considered as being aligned with the opening when the opening is arranged

completely in the window. The window of the fixation element may be considered as being aligned with the opening when an edge of the opening is completely arranged within the window. The window of the fixation element may be considered as being aligned with the opening when the opening does not comprise a part that is not overlapped by the window.

When the window is aligned to the opening, no edge of the window may be visible through the opening. When the window is aligned with the opening, it may not be possible for a cable that enters through the opening of the housing to touch the window .

The fixation element may be a fixing means which is

configured to fix a cable to a busbar of the terminal. As the window and the opening are aligned in the insertion state, it may be ensured that the fixing means do not obstruct the introduction of a cable into the terminal and, therefore, do not cause a splashing of the cable.

The terminal may ensure that stranded cables and fine- stranded cables can be assembled to the terminal and

disassembled from the terminal without splashing of the cable. Thereby, it can be ensured that the creepage distance between adjacent terminals or between a terminal and a metal housing is not reduced due to splashing and thus no risk of a voltage flashover is generated. Moreover, it is ensured that a contact area of the cable to a busbar of the terminal is not reduced by splashing, which would reduce the quality of the electrical contact.

The insertion state of the fixation element may be a state wherein the terminal is configured to receive a cable without any further manually operated steps. The insertion state may be characterized by the alignment of the opening and the window .

The fixing state of the fixation element may be a state wherein the opening is not aligned with the window. The fixing state may be a state wherein the fixation element fixes a cable to the terminal. The fixing state may be a state wherein a cable cannot be assembled to the terminal without performing a manually operated step before

introducing the cable into the terminal. This manually operated step may be the operation of a lever. The fixing state may be a state wherein a cable fixed to the terminal cannot be disassembled from the terminal without performing a manually operated step before introducing the cable.

In one embodiment, a cable can be inserted into the terminal through the opening in the housing and through the window in the fixation element when the fixation element is in its insertion state. The terminal may be configured to receive cables in a wide range of diameters. The diameter of the opening of the housing may form an upper limit for the allowed diameter of a cable that shall be fixed to the terminal. When the fixation element is a spring element, no lower limit regarding the diameter may be necessary, as the spring element may be compressed until a clamping of the cable is provided. In one embodiment, when the fixation element is in its fixing state, the cable may be mechanically fixed and electrically connected to the terminal by the fixation element.

In one embodiment, the fixation element is a spring element. The spring element may be configured to provide a clamping connection of the cable to the terminal in its fixing state. In alternative embodiments, the fixation element may be another type of fixation element. In principle, any element can be used as a fixation element which is enabled to fix a cable to the terminal .

When the fixation element is a spring element, the spring element may be compressed in its insertion state.

The terminal may comprise a lever, wherein the lever is movable to an open position and to a closed position, wherein the terminal is configured such that when the lever is moved into in its open position, the lever compresses the spring element and, thereby, moves the spring element into its insertion state. The terminal may be configured such that when the lever is moved from its open position to its closed position, the fixation element is moved into its fixing state .

When the lever is moved from its open position to its closed position, the spring element may at least partly relax and the window may be moved out of alignment with the opening of the housing.

The fixation element may abut the housing. Accordingly, no gap may be formed between the fixation element and the housing. Such a gap could cause splashing of a cable that is introduced into the terminal through the opening of the housing and the window of the fixation element. The abutment of the fixation element and the housing may, therefore, prevent splashing of a cable. The fixation element may abut an inner surface of the housing.

The terminal may be configured such that, when the fixation element moves from its insertion state to its fixing state, the window of the fixation element moves out of alignment with the opening of the housing until a further movement of the window is obstructed. The further movement of the window may be obstructed by the cable and/or a busbar.

The housing may have an outer surface and an inner surface. The outer surface may face away from a spaced enclosed by the housing and the inner surface may face to the space enclosed by the housing. The opening of the housing may be larger at the outer surface of the housing than at the inner surface of the housing. In particular, the opening may be cone-shaped or funnel-shaped. The shape of the opening may guide a movement of a cable when the cable is introduced into the housing. Thus, the shape of the opening may further decrease the risk of splashing the cable.

The housing may comprise a rail and wherein the rail is configured to guide a movement of the fixation element. The rail may ensure that the window of the fixation element is aligned with the opening of the housing when the fixation element is moved to the insertion state. The window may slide alone the rail.

The rail may be configured such that the window of the fixation element can only move perpendicular to the opening. The rail may be configured such that the window of the fixation element can only move parallel to an inner surface of the housing. Thus, in any state of the fixation element, the window may always be parallel to an outer surface of the housing. Thus, when a cable is introduced into the terminal, the cable can be introduced in a 90° angle to the outer surface. This may facilitate the assembly of a cable to the terminal for a user.

The terminal may be configured such that the window of the fixation element blocks the opening of the housing when no cable is arranged in the terminal and the fixation element is in its fixing state. In particular, it may not be possible to introduce a cable into the terminal when the fixation element blocks the opening. Thus, the blocking of the opening may prevent a user from not properly fixing a cable, thereby increasing the security of the terminal.

The housing may comprise a second opening which is arranged opposite of the opening, wherein the terminal comprises a second fixation element comprising a second window, wherein the second fixation element is movable to an insertion state and to a fixing state, wherein the second window of the second fixation element is aligned with the second opening of the housing when the second fixation element is in its insertion state. The second fixation element may be identical to the above described fixation element. All functional and structural features of the fixation element may also apply to the second fixation element. The second fixation element may be a spring element.

The fixation element and the second fixation element may be configured to provide a symmetric double side connection of the terminal . In one embodiment, a second cable can be inserted into the terminal through the second opening in the housing and through the second window in the second fixation element when the second fixation element is in its insertion state. The electronic power component may be connected in parallel by the cables.

The terminal may further comprise a discharge resistor which is fixed to the terminal by a plugging connection. The discharge resistor may be plugged onto an internal pin of the electronic power component.

According to a further aspect, the present invention concerns an electronic power component comprising a terminal. The terminal may be the above described terminal. The electronic power component may be a power capacitor.

In the following, preferred embodiments of the present invention are discussed with respect to the figures.

Figure 1 shows a terminal for a power electronic component in a cross-sectional view.

Figure 2 shows the terminal 1 in a perspective view.

Figure 3 shows a perspective view of the cross-section.

Each of figures 4 to 8 shows a fixation element.

Figure 9 shows a part of a terminal before an assembly of a cable .

Figure 10 shows the terminal after a first step of the assembly of a cable. Figure 11 shows the terminal after a second step of the assembly of the cable .

Figure 12 shows the terminal after a final step of the assembly of the cable.

Figure 13 shows an alternative embodiment of the terminal.

Figure 1 shows a terminal for a power electronic component in a cross-sectional view. Figure 2 shows the terminal 1 in a perspective view. Figure 3 shows a perspective view of the cross-section .

The terminal 1 is configured for a power electronic

component. In particular, the terminal 1 may be a terminal of a power electronic capacitor. The terminal 1 is configured to receive cables 2 and to connect the cables 2 electrically and mechanically to the power electronic component. In the embodiment shown in the Figures, six cables 2 are connected to the power electronic component by the terminal 1.

In particular, three cables 2 are connected to a first side face la of the terminal 1 and three cables 2 are connected to a second side face lb of the terminal 1 which is opposite of the first side face la. Accordingly, the terminal and, therefore the power electronic component, is connected in a double side three-phase type connection.

In alternative embodiments, the terminal 1 may be connected to an arbitrary other number of cables 2. The terminal 1 may also be connected in a single side connection wherein all cables 2 are connected to the same side of the terminal 1. Further, the terminal 1 comprises a housing 3. The housing 3 has a lower part 3a and an upper part 3b. The lower part 3a of the housing 3 faces towards the power electronic

component. The upper part 3b of the housing 3 faces away from the power electronic component. The lower part 3a of the housing 3 is a support block. The lower part 3a of the housing 3 and the upper part 3b of the housing 3 are

connected to each other by a snap connection.

The upper part 3b of the housing 3 comprises openings 4. In particular, the upper part 3b of the housing 3 comprises one opening 4 for each cable 2 which can be connected to the terminal 1. In the embodiment shown in the Figures, the openings 4 of the upper part 3b are arranged at the first side face la of the housing 3 and three openings 4 of the upper part 3b of the housing 3 are arranged at the second side face lb of the upper part 3b which is opposite of the first side face la.

The housing 3 has an outer surface 3c and an inner surface 3d. The inner surface 3d faces towards a space 15 that is enclosed by the housing 3. The outer surface 3c faces away from the space 15 that is enclosed by the housing 3. Each of the openings 4 has a larger diameter at the outer surface 3c of the housing 3 than at the inner surface 3d of the housing 3. Accordingly, as seen from the outside of the housing 3 to the inside, the openings 4 become narrower. In other words, each of the openings 4 is cone-shaped or funnel-shaped. This shape of the openings 4 facilitates an insertion of a cable 2 into the terminal 1. The shape of the opening 4 guides a movement of the cable 2 during the insertion of the cable 2.

Further, the housing 3 comprises a rail 5. In particular, the housing 3 comprises one rail 5 for each opening 4. The rails 5 are arranged at the inner surface 3d of the housing 3. The rails 5 extend in a direction perpendicular to the openings 4. Each rail 5 forms a straight line. As will be described later, the rails 5 are configured to guide a movement of a fixation element 6.

The terminal 1 further comprises fixation elements 6. In particular, the fixation elements 6 are spring elements. The fixation elements 6 are configured to provide a spring clamp connection wherein a cable 2 is fixed to the terminal 1 by clamping. In particular, the terminal 1 comprises one

fixation element 6, i.e. one spring element, for each cable 2 that can be connected to the terminal 1.

The terminal 1 comprises levers 7. In particular, the

terminal 1 comprises one lever 7 for each fixation element 6. Each of the levers 7 can be moved to an open position and to a closed position. In its open position, the lever 7

compresses the fixation element 6 that corresponds to the lever 7. In its closed position, the lever 7 does not abut the fixation element 6, thereby allowing the fixation element

6 to relax at least partly. Figures 1, 2 and 3 show the levers 7 in the closed position.

The terminal 1 also comprises a busbar 8. When the cables 2 are fixed to the terminal 1, an electrical connection is provided from the cable 2 via the busbar 8 to the power electronic component. The cables 2 fixed to the first side face la of the terminal 1 are electrically connected to the cables 2 fixed to the second side face lb of the terminal 1 by the busbar 8. The busbar 8 further comprises a hole 8a configured to receive an internal pin 9 of the electronic power component. Power can be transferred from the busbar 8 to the electronic power component and vice versa by the internal pin 9 arranged in the hole 8a of the busbar 8.

The terminal 1 further comprise a discharge resistor 10. The discharge resistor 10 is plugged onto an upper end 9a of the internal pin 9.

The housing 3 further comprises a chamber 11 which is separated from the space 15 enclosed by the housing 3. The chamber 11 is formed by the upper part 3b of the housing 3 and by a lid 12. The upper end 9a of the internal pin 9 protrudes into the chamber 11. The discharge resistor 10 is arranged in the chamber 11. The lid 12 is removably fixed to the upper part 3b. When the lid 12 is removed, the discharged resistor 10 can be plugged onto the internal pin 9.

The fixation elements 6 will be described in detail with respect to Figures 4 to 8.

Figure 4 shows a perspective view of one of the fixation elements 6 in a relaxed state. Figure 5 shows a perspective view of the fixation element 6 in the insertion state. Figure 6 shows the fixation element 6, the busbar 8 and parts of the housing 3 wherein the fixation element 6 is in its insertion state. Figure 7 shows the fixation element 6, the busbar 8 and parts of the housing 3 wherein the fixation element 6 is in its fixing state. Figure 8 shows a side view of three fixation elements 6, one fixation element 6a being in its relaxed state, one fixation element 6b being in its fixing state and one fixation element 6c being in its insertion state .

As mentioned above, each of the fixation elements 6 can be in the relaxed state, the insertion state or the fixing state. The fixation element 6 can be moved from one state to each of the two other states by a corresponding operation of a user.

The fixation element 6 comprises a window 13. The window 13 of the fixation element 6 is configured to receive further elements which are fixed to the fixation element 6 or which are fixed by the fixation element 6. In particular, the busbar 8 and a cable 2 can be arranged in the window 13. The window 13 has a lower end 13a and an upper end 13b. The lower end 13a of the window 13 faces towards the lower part 3a of the housing 3 when the fixation element 6 is assembled in the terminal 1. The lower end 13a of the window 13 is in contact with a cable 2 when the cable 2 is fixed by the fixation element 6 to the terminal 1. The upper end 13b of the window 13 is in contact with the busbar 8 when the cable 2 is fixed by the fixation element 6 to the terminal 1. The lower end 13a of the window 13 has a sharp edge. The sharp edge is configured to slightly cut into the cable 2 that is fixed by the fixation element 6. Thereby, the sharp edge of the lower end 13a acts as a claw which additionally fixes the cable 2 to the terminal 1 in addition to a clamping force applied by the fixation element 6.

Further, the fixation element 6 comprises a spring body 14. The spring body 14 comprises a first end section 14a, a middle section 14b and a second end section 14c. The middle section 14b is arranged between the first end section 14a and the second end section 14c. The spring body 14 and the window 13 are unitarily formed from a single piece of metal. The spring body 14 and the window 13 comprise spring steel. In particular, the spring body 14 and the window 13 consist of spring steel. The first end section 14a of the spring body 14 protrudes into the window 13. The first end section 14a of the spring body 14 separates the window 13 in an upper partition 13c and a lower partition 13d. The upper partition 13c of the window 13 extends from the upper end 13b of the window 13 to the first end section 14a of the spring body 14. The lower partition 13d of the window 13 extends from the first end section 14a of the spring body 14 to the lower end 13a of the window 13.

The fixation element 6 is configured such that the window 13 is moved relative to the first end section 14a when the fixation element 6 is tensed or when the fixation element 6 partly or completely relaxes. Accordingly, the size of the lower partition 13d of the window 13 and the size of the upper partition 13c of the window 13 change depending on the state of the fixation element 6. In its relaxed state, as shown in Figure 4, both of the upper partition 13c of the window 13 and the lower partition 13d of the window 13 have a size larger than zero. The first end section 14a of the spring body 14 neither abuts the lower end 13a of the window

13 nor the upper end 13b of the window 13. The lower

partition 13d of the window 13 has its minimal size in the relaxed state of the fixation element 6.

In the insertion state of the fixation element 6, as shown in

Figures 5 and 6, the first end section 14a of the spring body

14 abuts the upper end 13b of the window 13. In the insertion state, the first end section 14a is moved so far that there is no upper partition 13c of the window 13 due to the

abutment of the first end section 14a and the upper end 13b of the window 13 and that the window 13 consists only of the lower partition 13d. In the fixing state of the fixation element 6, as shown in Figure 7, the first end section 14a abuts neither the lower end 13a of the window 13 nor the upper end 13b of the window 13. Thus, the window 13 is separated in the lower partition 13d and the upper partition 13c. The lower partition 13d of the window 13 is larger in the fixing state than in the relaxed state of the fixation element 6.

The first end section 14a of the spring body 14 does not move relative to the housing 3 or the busbar 8 when the fixation element 6 is moved from its insertion state to its fixing state or vice versa. Instead, the window 13 moves relative to the housing 3 and to the busbar 8 when the fixation element 6 is moved from its insertion state to its fixing state or vice versa .

The middle section 14b of the spring body 14 connects the first end section 14a and the second end section 14c. The middle section 14b of the spring body 14 forms a curve. When the fixation element 6 is relaxed, the curve formed by the middle section 14b is shaped such that the first end section 14a and the second end section 14c point away from each other. When the fixation element 6 is compressed, the middle section 14b is compressed and the radius of the curve formed by the middle section 14b is reduced such that the first end section 14a and the second end section 14c of the spring body 14 are moved towards each other.

The second end section 14c of the spring body 14 is fixed to the upper end 13b of the window 13. When the middle section 14b is deformed due to a compression or a relaxation of the fixation element 6, the second end section 14c is moved relative to the housing 3. When the second end section 14c of the spring body 14 moves relative to the housing 3, the window 13 follows the movement of the second end section 14c.

In the insertion state, the fixation element 6 is compressed. The first end section 14a of the spring body 14 abuts the upper end 13b of the window 13. Thus, in this state, it is not possible to further compress the fixation element 6. The upper partition 13c of the window 13 is completely closed and the window 13 consists only of the lower partition 13d.

Figure 7 shows the fixation element 6 in its fixing state. In the fixing state, the fixation element 6 is partly

compressed. A further movement of the window 13 to further relax the fixation element 6 is prevented by an abutment of the window 13 with the busbar 8 which is arranged in the window 13. The first end section 14a of the spring body 14 and the lower end 13a of the window 13 both abut the busbar

Figures 1 and 3 also show the fixation element 6 in its fixing state. In the configuration shown in Figures 1 and 3, the busbar 8 and a cable 2 are arranged in the window 13 of the fixation element 6. A movement of the window 13 of the fixation element 6 is obstructed by the busbar 8 and the cable 2. In particular, the lower end 13a of the window 13 abuts the cable 2 and the first end section 14a of the spring body 14 abuts the busbar 8. The fixation element 6 thereby provides a clamping connection of the busbar 8 and the cable 2.

Figure 8 shows a side view of three fixation elements 6a, 6b, 6c wherein, for the sake of visualization, one fixation element 6a is shown in its relaxed state, one fixation element 6b in its fixing state and one fixation element 6c in its insertion state. Figure 8 shows that the window 13 is at its lowest position in the insertion state of the fixation element 6c and that the fixation element 6c is most

compressed in the insertion state. Further, Figure 8 shows that the fixation element 6b in the fixing state is more compressed than the fixation element 6a in the relaxed state.

Figure 8 also shows that the first end section 14a does not move relative to the busbar 8. The window 13 only moves in a direction perpendicular to the busbar 8 when the fixation element 6 is moved from its fixing state to its insertion state and vice versa. Accordingly, the window 13 only moves in a direction parallel to the inner surface 3d of the housing 3 when the fixation element 6 is moved from its fixing state to its insertion state and vice versa.

In the following, an assembly of a cable 2 to the terminal 1, and thereby to the power electric component, is described in detail :

Figure 9 shows a part of the terminal 1 wherein no cable 2 has been assembled to the terminal 1. The fixation element 6 is in its fixing state, wherein the busbar 8 is clamped between the lower end 13a of the window 13 and the first end section 14a of the spring body 14. The lever 7 is in its closed position. Accordingly, the lever 7 does not abut the fixation element 6 and does not apply pressure on the

fixation element 6.

The window 13 of the fixation element 6 is not aligned to the opening 4 of the housing 3. In particular, the lower end 13a of the window 13 blocks the opening 4 of the housing 3.

Accordingly, it is not possible to enter a cable 2 into the terminal 1 in this configuration. Thereby, the fixation element 6 provides an additional security feature as the user is prevented from falsely operating the terminal 1 by

introducing a cable 2 before operating the lever 7.

The first step of the assembly of the cable 2 to the terminal 1 is to move the lever 7 form its closed position to its open position. Figure 10 shows the terminal 1 after a user has moved the lever 7 from its closed position to its open position .

When the lever 7 is moved to its open position, the lever 7 abuts and compresses the fixation element 6. In particular, the lever 7 abuts the second end section 14c of the fixation element 6 and forces the second end section 14c to move towards the first end section 14a. Thereby, the middle section 14b of the spring body 14 is compressed and the radius of the curve formed by the middle section 14b is reduced. The window 13 follows the movement of the second end section 14c. The movement of the window 13 is guided by the rail 5 of the housing 3. The window 13 is moved into

alignment with the opening 4 in the housing 3. The fixation element 6 is compressed until the first end section 14a of the spring body 14 abuts the upper end 13b of the window 13 and a further compression of the fixation element 6 is not possible .

The movement of the window 13 is guided by the rail 5 such that the window 13 slides along the inner surface 3d of the housing 3. In particular, no gap is formed between the window 13 of the fixation element 6 and the inner surface 3d of the housing 3. Accordingly, when a stranded cable or a fine- stranded cable 2 is introduced into the terminal 1 through the opening 4 and the window 13, splashing of the cable 2 is prevented as there is no gap which could causes the

splashing .

The second step of the assembly of the cable 2 to the

terminal 1 is to move the cable 2 into the terminal 1 through the opening 4 of the housing 3 and through the window 13 of the fixation element 6. Figure 11 shows the terminal 1 after the cable 2 has been introduced into the terminal 1.

The lever 7 is still in its open position and compresses the fixation element 6. Thus, the fixation element 6 is in its insertion state. Accordingly, in this configuration, the window 13 does not provide a clamping force onto the cable 2 and, instead, allows a smooth entry of the cable 2 due to the alignment of the window 13 with the opening 4. The window 13 and the opening 4 are perpendicular to a cable path along which the cable 2 is moved into the terminal 1. Thus, the cable 2 can be introduced perpendicular to the outer surface 3c of the housing 3.

The final step of the assembly of the cable 2 to the terminal 1 is to move the lever 7 from its open position to its closed position after the cable 2 has been introduced into the terminal 1. Figure 12 shows the terminal 1 after the final step of the assembly of the cable 2.

In its closed position, the lever 7 is moved away from the fixation element 6. Accordingly, the lever 7 no longer abuts the fixation element 6 and, thereby, allows the fixation element 6 to relax partly. The fixation element 6 relaxes until the lower end 13a of the window 13 abuts the cable 2. The fixation element 6 is now in its fixing state. In this configuration, the fixation element 6 provides a clamping force which fixes the cable 2 to the busbar 8. The above-described assembly process can be performed with all kinds of cables 2. In particular, cables 2 having a wide range of diameters can be connected to the terminal 1. The fixation element 6 adapts to the diameter of the cable 2 as the fixation element 6 relaxes until it clamps the cable 2.

The cable 2 can be disassembled from the terminal 1 by moving the lever 7 to its open position, then by removing the cable 2 from the terminal 1 and then by moving the lever 7 to its closed position.

Figure 13 shows an alternative embodiment of the terminal 1. According to the alternative embodiment, the terminal 1 is configured such that cables 2 can only be connected to the first side face la of the terminal 1. The housing 3 does not comprise an opening 4 at the second side face lb of the terminal 1. The housing 3 comprises openings 4 only on the first side face la. Further, the terminal 1 comprises levers 7 and fixation elements 6 only close to the first side face la .

The double side spring clamp connection shown in the first embodiment allows to connect the power electronic component in a symmetric parallel connection. The possibility to block one side of the terminal 1, as shown in Figure 13, allows the connection of one side only. Some power electronic components require a single side connection. Reference numbers

1 terminal

la first side face lb second side face

2 cable

3 housing

3a lower part of housing

3b upper part of housing

3c outer surface

3d inner surface

4 opening

5 rail

6 fixation element

6a fixation element

6b fixation element

6c fixation element

7 lever

8 busbar

8a hole

9 internal pin

9a upper end

10 discharge resistor 11 chamber

12 lid

13 window

13a lower end of window 13b upper end of window 13c upper partition

13d lower partition

14 spring body

14a first end section 14b middle section 14c second end section

15 space