EMC circuit of new energy automobile
By connecting inductors and capacitors in series to form a filter circuit in the EMC circuit of new energy vehicles, the problem of abnormal ripple current affecting the safety of power batteries and vehicles is solved, a smoother DC voltage is achieved, and the safety and stability of electronic devices are ensured. .
Patent Information
- Application Number
- CN202420530941.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-19
- Publication Date
- 2025-02-07
- Estimated Expiration
- 2034-03-19
AI Technical Summary
In the field of new energy vehicles, abnormal ripple current will affect the operating quality of power batteries and their management systems, and even affect the safety performance of the entire vehicle. The existing technology has not effectively solved this problem.
Design an EMC circuit for a new energy vehicle, and by connecting inductors and capacitors in series between the circuit and the load, the ripple of the load voltage is reduced, thereby meeting the requirements of EMC testing.
Through a filtering circuit that connects inductors and capacitors in series, the ripple of the output voltage is effectively reduced, and a smoother DC voltage is obtained, ensuring the safety and stability of new energy vehicle electronic devices.
Smart Images
Figure CN222441583U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of automobile electronics, in particular to an EMC circuit of a new energy automobile. Background Art
[0002] EMC testing, also known as electromagnetic compatibility (EMC) testing, refers to the comprehensive assessment of the interference size and anti-interference ability of electronic products in electromagnetic fields. It is one of the most important indicators of product quality. The purpose of EMC testing is to detect the impact of electromagnetic radiation generated by electrical products on the human body, public power grids, and other normally working electrical products.
[0003] Ripple is a phenomenon caused by voltage fluctuations in a DC stabilized power supply. Because a DC stabilized power supply is generally formed by an AC power supply through rectification and voltage stabilization, it is inevitable that there will be some AC components in the DC stabilized quantity. This AC component superimposed on the DC stabilized quantity is called ripple.
[0004] Ripple can easily generate harmonics of various frequencies in electrical appliances. In the field of new energy vehicles, if the ripple current is abnormal, it will not only affect the operating quality of the power battery and its management system, but in severe cases it will even affect the safety performance of the entire vehicle. Therefore, in the field of new energy vehicles, EMC testing is also required to detect the impact of ripple on automotive electrical appliances. However, there is currently no similar technology that can help reduce the ripple of the load voltage to pass the EMC test of new energy vehicles.
[0005] Based on the above reasons, the utility model designs an EMC circuit for new energy vehicles. By connecting an inductor and a capacitor in series between the circuit and the load to form a filter circuit, the ripple of the load voltage can be further reduced, thereby meeting the requirements of the EMC test. Summary of the invention
[0006] The purpose of the utility model is to overcome the shortcomings of the prior art and provide an EMC circuit for new energy vehicles. By connecting an inductor and a capacitor in series between the circuit and the load to form a filter circuit, the ripple of the load voltage can be further reduced, thereby meeting the requirements of the EMC test.
[0007] In order to achieve the above-mentioned purpose, the utility model provides an EMC circuit for a new energy vehicle, including a bidirectional motor, a positive pole, a negative pole, a resistor, a capacitor 1, a capacitor 3, a capacitor 2, an inductor 1 and an inductor 2. A resistor is connected in parallel between the positive pole and the negative pole of the bidirectional motor, the resistor is connected in parallel with the capacitor 1, an inductor 2 is connected in series between the positive pole and the bidirectional motor, the inductor 2 is connected to the capacitor 2, the capacitor 2 is grounded, an inductor 1 is connected in series between the negative pole and the bidirectional motor, the inductor 1 is connected to the capacitor 3, and the capacitor 3 is grounded.
[0008] The positive and negative poles can be switched.
[0009] The inductor 1 and inductor 2 are selected to be 6uH.
[0010] Capacitor 1 is 0.47uF.
[0011] Capacitor 3 and capacitor 2 are selected to be 4.7nF.
[0012] Compared with the prior art, the utility model connects an inductor and a capacitor in series on the positive and negative poles of the bidirectional motor respectively, so that the AC component can be dropped on the inductor, and the energy storage effect of the inductor can be used to reduce the ripple of the output voltage. The DC component is transmitted to the bidirectional motor with almost no attenuation. At the same time, the AC component falls into the capacitor, and the DC component falls directly into the bidirectional motor, thereby obtaining a smoother DC. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 It is a circuit diagram of the utility model.
[0014] Figure 2 The test results of the utility model are shown in FIG. Figure 1 .
[0015] Figure 3 The test results of the utility model are shown in FIG. Figure 2 .
[0016] Figure 4 The test results of the utility model are shown in FIG. Figure 3 .
[0017] Description of reference numerals:
[0018] 1 bidirectional motor, 2 positive pole, 3 negative pole, 4 resistor, 5 capacitor one, 6 capacitor three, 7 capacitor two, 8 inductor one, 9 inductor two. DETAILED DESCRIPTION
[0019] The utility model is now further described with reference to the accompanying drawings.
[0020] See also Figures 1 to 4 The utility model provides an EMC circuit for a new energy vehicle, including a bidirectional motor 1, a positive pole 2, a negative pole 3, a resistor 4, a capacitor 1 5, a capacitor 3 6, a capacitor 2 7, an inductor 1 8 and an inductor 2 9. The resistor 4 is connected in parallel between the positive pole 2 and the negative pole 3 of the bidirectional motor 1, the resistor 4 is connected in parallel with the capacitor 1 5, the inductor 2 9 is connected in series between the positive pole 2 and the bidirectional motor 1, the inductor 2 9 is connected to the capacitor 2 7, the capacitor 2 7 is grounded, the inductor 1 8 is connected in series between the negative pole 3 and the bidirectional motor 1, the inductor 1 8 is connected to the capacitor 3 6, and the capacitor 3 6 is grounded.
[0021] The positive electrode 2 and the negative electrode 3 can be switched with each other.
[0022] The inductor 1 8 and the inductor 2 9 are selected to be 6uH.
[0023] Capacitor 15 is 0.47uF.
[0024] Capacitor 3 6 and capacitor 2 7 are selected to be 4.7nF.
[0025] Working principle:
[0026] See also Figure 1 Since the bidirectional motor 1 can switch between positive and negative poles, the positive and negative poles of the bidirectional motor 1 are respectively connected in series with an inductor 1 8 and an inductor 2 9, and are respectively connected with a capacitor 3 6 and a capacitor 2 7. The capacitor 2 7 and the capacitor 3 6 are equivalent to an open circuit for DC, but present a small impedance for AC. , specifically , where f is the frequency in Hz, is the angular frequency, unit is 1 / s, so the rectified DC component all flows through the bidirectional motor 1, and the AC component falls on capacitor 2 7 and capacitor 3 6.
[0027] The impedance of inductor 1 8 and inductor 2 9 to DC is zero. The resistance of the coil in the inductor can be ignored, but it presents a large impedance to AC. , where inductive reactance As the frequency of the alternating current increases, the inductive reactance increases. Therefore, the rectified DC component is transmitted to the bidirectional motor 1 with almost no attenuation, but most of the AC component falls on the inductor 1 8 and the inductor 2 9. The AC component on the bidirectional motor 1 is very small, and its voltage is close to the DC voltage. Therefore, the energy storage function of the inductor 1 8 and the inductor 2 9 can reduce the ripple of the output voltage, thereby obtaining a relatively smooth DC.
[0028] See also Figures 2 to 4 , the EMC requirement for new energy vehicles is within the frequency range of 0.15 to 1000MHz, and its interference level should be below the limit. After calculation and experiment, the inductor 1 8 and the inductor 2 9 are selected to be 6uH, the capacitor 1 5 is selected to be 0.47uF, the capacitor 2 7 and the capacitor 3 6 are selected to be 4.7nF to form the EMC circuit, which can meet the EMC test requirements.
[0029] The above are only preferred implementations of the present invention, which are only used to help understand the method and core ideas of the present application. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the idea of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.
[0030] The utility model solves the problem in the prior art that in the field of new energy vehicles, if the ripple current is abnormal, it will not only affect the operating quality of the power battery and its management system, but even affect the safety performance of the entire vehicle in severe cases, and there is no corresponding solution in the prior art. By connecting an inductor and a capacitor in series on the positive and negative poles of the bidirectional motor respectively, the AC component can be dropped on the inductor, and the energy storage effect of the inductor can be used to reduce the ripple of the output voltage. The DC component is conducted to the bidirectional motor with almost no attenuation. At the same time, the AC component falls into the capacitor, and the DC component falls directly into the bidirectional motor, thereby obtaining a smoother DC, which provides a guarantee for the safety and stability of electronic devices in new energy vehicles.
Claims
1. An EMC circuit for a new energy vehicle, characterized in that: The invention comprises a bidirectional motor (1), a positive pole (2), a negative pole (3), a resistor (4), a capacitor 1 (5), a capacitor 3 (6), a capacitor 2 (7), an inductor 1 (8) and an inductor 2 (9), wherein a resistor (4) is connected in parallel between the positive pole (2) and the negative pole (3) of the bidirectional motor (1), the resistor (4) is connected in parallel with the capacitor 1 (5), an inductor 2 (9) is connected in series between the positive pole (2) and the bidirectional motor (1), the inductor 2 (9) is connected to the capacitor 2 (7), the capacitor 2 (7) is grounded, an inductor 1 (8) is connected in series between the negative pole (3) and the bidirectional motor (1), the inductor 1 (8) is connected to the capacitor 3 (6), and the capacitor 3 (6) is grounded.
2. The EMC circuit of the new energy vehicle according to claim 1, characterized in that: The positive electrode (2) and the negative electrode (3) can be switched with each other.
3. The EMC circuit of the new energy vehicle according to claim 1, characterized in that: The inductor 1 (8) and the inductor 2 (9) are selected to be 6uH.
4. The EMC circuit of the new energy vehicle according to claim 1, characterized in that: The capacitor 1 (5) is selected to be 0.47uF.
5. The EMC circuit of the new energy vehicle according to claim 1, characterized in that: The capacitor three (6) and capacitor two (7) are selected to be 4.7nF.