Passive signal filter for processing CP signal transmission within AC charging piles

Abstract

This utility model discloses a passive signal filter for processing CP signal transmission in AC charging piles, belonging to the field of new energy vehicle charging technology. It includes a first signal path 1-1' and a second signal path 2-2'. Multiple differential-mode inductors L are connected in series on both the first and second signal paths 1-1' and 2-2'. A through-hole capacitor C1 is connected in parallel at both the input and output terminals of the first signal path 1-1', with the other end of C1 grounded. Similarly, a through-hole capacitor C1 is connected in parallel at both the input and output terminals of the second signal path 2-2', with the other end of C1 grounded. A through-hole capacitor C2 is connected in parallel between the series connection node of two adjacent differential-mode inductors L on both the first and second signal paths 1-1' and 2-2' and ground. This passive CP filter enables direct PWM transmission without significant signal distortion, meeting the noise floor requirements for anechoic chamber testing.

Description

Technical Field

[0001] This utility model relates to the field of new energy vehicle charging technology, specifically to a passive signal filter for processing CP signal transmission within an AC charging pile. Background Technology

[0002] With the popularization of new energy vehicles and the rapid development of vehicle charging technology, more stringent requirements have been placed on the EMC performance of vehicle electrical components under various conditions. Good EMC performance is a necessary condition to ensure the vehicle's performance during charging, starting, driving, and parking (braking).

[0003] Currently, in AC charging technology, such as Figure 1 As shown, the charging pile has 7 interfaces: L1, L2, L3, N, PE, CC, and CP. L1, L2, L3, and N are power interfaces, PE is ground, CC is the charging connection confirmation signal, and CP is the control guidance signal. In the automotive electronic anechoic chamber, L1, L2, L3, and N are processed using a three-phase four-wire power filter; PE is directly grounded without processing; the CC interface uses a signal filter; and CP outputs a PWM wave.

[0004] Because the CP signal is transmitted in the form of a PWM square wave, conventional filters cannot meet the requirements for signal transmission, and there are currently no matching filters on the market. Traditional signal filters cannot simultaneously address the transmission of PWM signals and EMC performance in anechoic chamber environments (PWM waves are easily distorted by traditional signal filters, or the signal may not even be transmitted at all). Existing solutions generally use photoelectric conversion to transmit signals into the anechoic chamber. One approach is to use an integrated CP filter, and the other is to use a separate CP filter. However, neither approach can solve the problem of EMC anechoic chamber testing noise floor because the optical transceiver itself generates interference, increasing the testing noise floor.

[0005] Based on this, the present invention designs a passive signal filter for processing CP signal transmission within an AC charging pile to solve the above problems. Utility Model Content

[0006] To address the aforementioned shortcomings of existing technologies, this invention provides a passive signal filter for processing CP signal transmission within AC charging piles. It enables AC charging piles to test EMC performance during electric vehicle charging and to shield CP signals.

[0007] To achieve the above objectives, this utility model provides the following technical solution: The passive signal filter used to process the CP signal transmission in the AC charging pile includes two parallel signal transmission paths, namely the first signal path 1-1' and the second signal path 2-2'. Multiple differential mode inductors L are connected in series in both the first signal path 1-1' and the second signal path 2-2'. A through-core capacitor C1 is connected in parallel at the input and output terminals of the first signal path 1-1', and the other end of the through-core capacitor C1 is grounded; a through-core capacitor C1 is also connected in parallel at the input and output terminals of the second signal path 2-2', and the other end of the through-core capacitor C1 is grounded. On the first signal path 1-1', a through-hole capacitor C2 is connected in parallel between the series node of two adjacent differential mode inductors L and ground; on the second signal path 2-2', a through-hole capacitor C2 is also connected in parallel between the series node of two adjacent differential mode inductors L and ground.

[0008] Furthermore, three differential mode inductors L are connected in series on both the first signal path 1-1' and the second signal path 2-2'.

[0009] Furthermore, the number of differential mode inductors L is three.

[0010] Furthermore, the number of core capacitors C2 is three.

[0011] Compared to existing technologies, the advantages of this invention are as follows: This invention forms a multi-stage differential-mode filter topology of "inductor series connection + capacitor parallel connection" by connecting differential-mode inductors in series on two parallel signal transmission paths and connecting through-hole capacitors in parallel at the signal path terminations and inductor nodes. The passive CP filter of this invention can achieve direct PWM transmission without significant signal distortion, meeting the noise floor requirements for anechoic chamber testing. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 It provides 7 interfaces for existing AC charging piles.

[0014] Figure 2 This is a schematic diagram of the passive signal filter of this utility model for processing CP signal transmission in AC charging piles. Figure 3 This is a structural diagram of the passive signal filter of this utility model used for processing CP signal transmission in AC charging piles. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0016] Example 1: In some embodiments, please refer to the accompanying drawings. Figure 2-3 A passive signal filter for processing CP signal transmission in AC charging piles includes two parallel signal transmission paths, namely the first signal path 1-1' and the second signal path 2-2'. Multiple differential mode inductors L are connected in series in both the first signal path 1-1' and the second signal path 2-2'. A through-core capacitor C1 is connected in parallel at the input and output terminals of the first signal path 1-1', and the other end of the through-core capacitor C1 is grounded; a through-core capacitor C1 is also connected in parallel at the input and output terminals of the second signal path 2-2', and the other end of the through-core capacitor C1 is grounded. On the first signal path 1-1', a through-core capacitor C2 is connected in parallel between the series node of two adjacent differential mode inductors L and ground; on the second signal path 2-2', a through-core capacitor C2 is also connected in parallel between the series node of two adjacent differential mode inductors L and ground. Preferably, the number of differential mode inductors L is three, and the number of feedthrough capacitors C2 is three, thus forming a three-stage filter structure; Among them, the through-core capacitor C1 and through-core capacitor C2 are the ground capacitances (i.e., Cy capacitors) in the line, that is, one end is connected to the line and the other end is directly connected to the filter housing, i.e., grounded.

[0017] The basic principle of pulse width modulation (PWM) is as follows: Control method—controlling the on / off state of the switching devices in the inverter circuit to obtain a series of pulses of equal amplitude at the output. These pulses replace the sine wave or the desired waveform. In other words, multiple pulses are generated within half a cycle of the output waveform, ensuring that the equivalent voltage of each pulse is a sine wave, resulting in a smooth output with fewer low-order harmonics. By modulating the width of each pulse according to certain rules, the magnitude of the inverter circuit's output voltage and the output frequency can be changed.

[0018] This invention forms a multi-stage differential-mode filter topology of "inductor series + capacitor parallel" by connecting differential-mode inductors in series on two parallel signal transmission paths and connecting through-hole capacitors in parallel at the signal path terminations and inductor nodes. The passive CP filter of this invention enables direct PWM transmission without significant signal distortion, meeting the noise floor requirements for anechoic chamber testing.

[0019] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A passive signal filter for processing CP signal transmission in an AC charging pile, characterized in that, The two parallel signal transmission paths are a first signal path 1-1' and a second signal path 2-2'; On the first signal path 1-1' and the second signal path 2-2', a plurality of differential mode inductors L are connected in series; On the input end and the output end of the first signal path 1-1', a through-hole capacitor C1 is connected in parallel, and the other end of the through-hole capacitor C1 is grounded; on the input end and the output end of the second signal path 2-2', a through-hole capacitor C1 is also connected in parallel, and the other end of the through-hole capacitor C1 is grounded; On the first signal path 1-1', a through-hole capacitor C2 is connected in parallel between the series connection node of two adjacent differential mode inductors L and the ground; on the second signal path 2-2', a through-hole capacitor C2 is also connected in parallel between the series connection node of two adjacent differential mode inductors L and the ground.

2. The passive signal filter for processing CP signal transmission in AC charging piles according to claim 1, wherein, On the first signal path 1-1' and the second signal path 2-2', three differential mode inductors L are connected in series.

3. The passive signal filter for processing CP signal transmission in AC charging piles according to claim 2, characterized in that, The number of differential mode inductors L is three.

4. The passive signal filter for processing CP signal transmission in AC charging piles according to claim 3, characterized in that, The number of through-hole capacitors C2 is three.

Images