Harmonic suppression circuit and device and vehicle-mounted control system

Abstract

The utility model provides a harmonic suppression circuit and device and a vehicle-mounted control system, and relates to the technical field of new energy automobiles, the harmonic suppression circuit and device are applied to the vehicle-mounted control system, the vehicle-mounted control system comprises a motor control circuit and an air conditioner control circuit, and the harmonic suppression circuit comprises at least one diode which is connected between the motor control circuit and the air conditioner control circuit; and the capacitor is used for generating a capacitance effect and changing a loop resonance point between the motor control circuit and the air conditioner control circuit so as to suppress loop current between the motor control circuit and the air conditioner control circuit. According to the invention, the loop between the motor control circuits does not generate resonance under the working frequency of the vehicle-mounted control system, the loop current between the motor control circuits is suppressed, and the technical problem of how to suppress the loop current in the vehicle-mounted control system is solved. The safety of the motor control circuit and devices in the motor control circuit is ensured, and the safety of the vehicle-mounted control system is improved.

Description

Technical Field

[0001] The present application relates to the field of new energy vehicle technology, and in particular to a harmonic suppression circuit, device and vehicle-mounted control system. Background Art

[0002] In the related art, the motor control circuit and the air-conditioning control circuit of the vehicle control system are both powered by a high-voltage DC power bus. A loop is formed between the two control circuits through the power bus and the bus capacitor. When the motor control circuit and / or the air-conditioning control circuit are working, a resonant current is easily generated in the loop between the two control circuits, resulting in excessive loop current and damage to the devices in the two control circuits.

[0003] Therefore, the problem of how to suppress the loop current in the vehicle control system needs to be solved urgently. Utility Model Content

[0004] The main purpose of this application is to provide a harmonic suppression circuit, device and vehicle-mounted control system, aiming to solve the technical problem of how to suppress the loop current in the vehicle-mounted control system.

[0005] To achieve the above objectives, this application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a harmonic suppression circuit, which is applied to a vehicle control system. The vehicle control system includes a motor control circuit and an air conditioning control circuit. The harmonic suppression circuit includes:

[0007] At least one diode is connected between the motor control circuit and the air conditioning control circuit to generate a capacitive effect, change the loop resonance point between the motor control circuit and the air conditioning control circuit, and suppress the loop current between the motor control circuit and the air conditioning control circuit.

[0008] Optionally, at least one diode is connected in series to a power bus between the motor control circuit and the air conditioning control circuit.

[0009] Optionally, the vehicle control system further includes two bus capacitors, any one of the two bus capacitors is connected to the power bus at the motor control circuit end, and the other bus capacitor other than any one of the two bus capacitors is connected to the power bus at the air conditioning control circuit end;

[0010] At least one diode is connected in series to the power bus between the two bus capacitors.

[0011] Optionally, the number of the diode is one, and the diode is connected in series to the positive electrode or the negative electrode of the power bus.

[0012] Optionally, there are multiple diodes, and the multiple diodes are respectively connected in series to the positive electrode and / or the negative electrode of the power bus.

[0013] Optionally, the two bus capacitors include a first capacitor C r1 and the second capacitor C r2 ;

[0014] The first capacitor C r1 One end of the first capacitor C is connected to the positive electrode of the power bus at the motor control circuit end. r1 The other end is connected to the negative pole of the power bus at the motor control circuit end;

[0015] The first capacitor C r2 One end of the first capacitor C is connected to the positive electrode of the power bus at the air conditioning control circuit end. r2 The other end is connected to the negative pole of the power bus at the air conditioning control circuit end.

[0016] Optionally, the at least one diode comprises a diode D;

[0017] The anode of the diode D and the first capacitor C r1 Connect the cathode of diode D to the second capacitor C r2 connect.

[0018] In a second aspect, the present application provides a harmonic suppression device, the harmonic suppression device comprising:

[0019] Such as the harmonic suppression circuit mentioned above.

[0020] In a third aspect, the present application provides a vehicle-mounted control system, the vehicle-mounted control system comprising:

[0021] Motor control circuit and air conditioning control circuit;

[0022] A harmonic suppression circuit as described above is connected between the motor control circuit and the air conditioning control circuit.

[0023] Optionally, the motor control circuit includes a first power module, and the air conditioning control circuit includes a second power module;

[0024] The first power module is connected to the power battery and the power motor respectively, and is used to work according to the received motor control signal to drive the power motor;

[0025] The second power module is connected to the power battery and the air-conditioning motor respectively, and is used to work according to the received air-conditioning control signal to drive the air-conditioning motor.

[0026] The above one or more technical solutions provided by this application may have the following advantages or at least achieve the following technical effects:

[0027] The present application provides a harmonic suppression circuit, device and vehicle-mounted control system, which are applied to the vehicle-mounted control system. The vehicle-mounted control system includes a motor control circuit and an air-conditioning control circuit. The harmonic suppression circuit includes: at least one diode, both of which are connected between the motor control circuit and the air-conditioning control circuit, and are used to reduce the loop voltage between the motor control circuit and the air-conditioning control circuit, and change the loop resonance point between the motor control circuit and the air-conditioning control circuit to suppress the loop current between the motor control circuit and the air-conditioning control circuit.

[0028] Therefore, the present application generates a capacitance effect by connecting at least one diode between the motor control circuit and the motor control circuit, thereby changing the loop resonance point, so that the loop between the motor control circuit and the motor control circuit will not resonate at the operating frequency of the vehicle control system, thereby suppressing the loop current between the motor control circuit and the motor control circuit, solving the technical problem of how to suppress the loop current in the vehicle control system, ensuring the safety of the motor control circuit and the devices in the motor control circuit, and improving the safety of the vehicle control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0030] Figure 1 A connection diagram of the first embodiment of the vehicle-mounted control system provided by the utility model;

[0031] Figure 2 This is a circuit schematic diagram of an implementation scheme of a vehicle-mounted control system provided by the utility model.

[0032] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0034] It should be noted that in this application, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a device or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a device or system. In the absence of more restrictions, an element defined by the sentence "includes..." does not exclude the existence of other identical elements in the device or system including the element.

[0035] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] In this application, the meaning of "and / or" in the whole text includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the protection scope required by this application.

[0037] With the development of new energy technologies, electric vehicles are gradually replacing fuel vehicles and becoming an important tool for human life and production. And with the increasing global shortage of oil energy and environmental pollution, electric vehicles have been rapidly developed due to their advantages of no pollution, no noise, and energy saving. Different from traditional internal combustion engines, electric vehicles convert the electrical energy of power batteries into mechanical energy through motor control circuits to drive the vehicle. At the same time, car air conditioners can also be directly powered by power batteries, and no additional energy conversion system is required, which is conducive to improving the efficiency of the entire vehicle and reducing the size of the air conditioning system.

[0038] At present, both the motor control circuit and the air conditioning control circuit include bus capacitors and IGBTs (Insulate-Gate Bipolar Transistor). The bus capacitor has the function of storing energy and smoothing the bus voltage, which is beneficial to prolonging the service life of the battery and facilitating the stable operation of the motor control circuit. In the vehicle architecture, the high voltage of the motor control circuit and the air conditioning control circuit comes from the high-voltage DC power bus output by the battery. Therefore, when any one of the control circuits is working or the two control circuits are working at the same time, a loop can be formed between the two control circuits through the power bus and bus capacitors. The size of the loop current is closely related to the matching of the vehicle, that is, it is related to the loop stray inductance, power bus, bus capacitor and switching frequency in the control circuit. When this current is large, it is easy to damage the components in the motor control circuit and the air conditioning control circuit.

[0039] Based on the current vehicle control system architecture, the loop current between the motor control circuit and the air conditioning control circuit is unavoidable and uncontrollable. In particular, the variable carrier frequency of the motor control circuit makes it easy for the loop between the motor control circuit and the air conditioning control circuit to resonate. Once resonance occurs, the loop current will increase greatly, causing irreversible damage to the components in the motor control circuit and the air conditioning control circuit. The damage is mainly reflected in two aspects: (1) the loop current exceeds the maximum current allowed by the device, causing damage to the device; (2) the loop current is large, causing the device to heat up for a long time and be damaged. Therefore, the problem of how to suppress the loop current in the vehicle control system needs to be solved urgently.

[0040] The harmonic suppression circuit, device and vehicle-mounted control system of the present application are described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0041] Embodiment 1

[0042] Reference Figure 1 and 2 , Figure 1 This is a connection diagram of the first embodiment of the vehicle-mounted control system provided by the utility model. Figure 2 This is a circuit schematic diagram of an implementation scheme of a vehicle-mounted control system provided by the utility model.

[0043] This embodiment provides a harmonic suppression circuit, which is applied to a vehicle control system. The vehicle control system may include a motor control circuit and an air conditioning control circuit, such as Figure 1 As shown, the harmonic suppression circuit may include:

[0044] At least one diode is connected between the motor control circuit and the air conditioning control circuit to generate a capacitive effect, change the loop resonance point between the motor control circuit and the air conditioning control circuit, and suppress the loop current between the motor control circuit and the air conditioning control circuit.

[0045] In this embodiment, the motor control circuit includes a first power module, and the air-conditioning control circuit includes a second power module; the first power module is respectively connected to the power battery and the power motor, and is used to work according to the received motor control signal to drive the power motor; the second power module is respectively connected to the power battery and the air-conditioning motor, and is used to work according to the received air-conditioning control signal to drive the air-conditioning motor.

[0046] The first power module and the second power module are both connected to the power battery through the power bus. By controlling the on and off of the power devices in the first power module and the second power module, the driving of the power motor and the air-conditioning motor can be realized accordingly.

[0047] In this embodiment, at least one diode is connected in series to the power bus between the motor control circuit and the air conditioning control circuit.

[0048] It is understandable that Figure 2 As shown, a loop is formed between the motor control circuit and the air-conditioning control circuit through the power bus. When the motor control circuit and / or the air-conditioning control circuit are working, the stray capacitance and stray inductance on the power bus will produce resonance. Therefore, at least one diode needs to be connected in series to the power bus between the motor control circuit and the air-conditioning control circuit.

[0049] In this embodiment, if Figure 2 As shown, the vehicle control system also includes two bus capacitors, one of the two bus capacitors is connected to the power bus at the motor control circuit end, and the other bus capacitor other than one of the two bus capacitors is connected to the power bus at the air conditioning control circuit end;

[0050] At least one diode is connected in series to the power bus between the two bus capacitors.

[0051] It can be understood that when the motor control circuit and / or the air conditioning control circuit are working, the resonant frequency between the motor control circuit and the air conditioning control circuit is also related to the two bus capacitors. Therefore, at least one diode needs to be connected in series to the power bus between the two bus capacitors.

[0052] In this embodiment, if Figure 2 As shown, the two bus capacitors may include a first capacitor C r1 and the second capacitor C r2 ;

[0053] The first capacitor C r1 One end of the first capacitor C is connected to the positive electrode of the power bus at the motor control circuit end. r1 The other end is connected to the negative pole of the power bus at the motor control circuit end;

[0054] The first capacitor C r2 One end of the first capacitor C is connected to the positive electrode of the power bus at the air conditioning control circuit end. r2 The other end is connected to the negative pole of the power bus at the air conditioning control circuit end.

[0055] When the motor control circuit and / or the air conditioning control circuit are working, there are multiple resonant frequencies in the loop between the motor control circuit and the air conditioning control circuit, as shown in the following formula:

[0056]

[0057]

[0058]

[0059] L r is the total loop inductance between the motor control circuit and the air conditioning control circuit, including stray inductance and wire inductance, etc., C r is the circuit stray capacitance, C r1 is the bus capacitance at the motor control circuit end, C r2 It is the bus capacitor at the air conditioning control circuit end.

[0060] When a diode is connected between the motor control circuit and the air conditioning control circuit, a voltage drop U will be generated on the diode due to the internal resistance of the diode, which is related to the voltage applied across the diode. s , so that the loop current I between the motor control circuit and the air conditioning control circuit is:

[0061]

[0062] Among them, z is the total impedance of the loop, R is the total internal resistance of at least one diode, ω is the angular frequency of the loop current, L is the total inductance of the loop, and c is the total capacitance of the loop. Therefore, at least one diode will produce a voltage drop, thereby reducing the loop voltage between the motor control circuit and the air conditioning control circuit, thereby suppressing the loop current between the motor control circuit and the air conditioning control circuit.

[0063] In this embodiment, when a forward voltage is applied to at least one diode, a diffusion capacitance effect is generated to change the loop resonance point.

[0064] It can be understood that when the motor control circuit and / or the air-conditioning control circuit are working, the external voltage of the diode can be a forward voltage. At this time, a large current flows through the diode, the depletion region of the PN junction of the diode becomes narrower, and the capacitance becomes larger, resulting in a diffuse capacitance effect, which is equivalent to connecting a capacitor in series between the motor control circuit and the air-conditioning control circuit, so that the loop resonance point between the motor control circuit and the air-conditioning control circuit changes, thereby suppressing the loop current between the motor control circuit and the air-conditioning control circuit.

[0065] In this embodiment, when a reverse voltage is applied to at least one diode, an excess capacitance effect is generated to change the loop resonance point.

[0066] It can be understood that when the motor control circuit and / or the air-conditioning control circuit are working, the external voltage of the diode can be a reverse voltage. At this time, the diode produces an excessive capacitance effect, which is equivalent to connecting a capacitor in series between the motor control circuit and the air-conditioning control circuit, so that the loop resonance point changes, thereby suppressing the loop current between the motor control circuit and the air-conditioning control circuit.

[0067] Therefore, in this embodiment, at least one diode is set between the motor control circuit and the air-conditioning control circuit, which can reduce the loop voltage and change the loop resonance point when the motor control circuit and / or the air-conditioning control circuit is in operation, so as to suppress the loop current between the motor control circuit and the air-conditioning control circuit and ensure the safety of the motor control circuit and the air-conditioning control circuit.

[0068] In this embodiment, when the number of the diode is one, the diode is connected in series to the positive electrode or the negative electrode of the power bus.

[0069] It can be understood that when there is only one diode, the diode can be connected in series to the positive or negative pole of the power bus between the two bus capacitors, and the connection direction of the positive and negative poles of the diode can be determined according to actual usage.

[0070] Preferably, if Figure 2 As shown, the at least one diode may include a diode D;

[0071] The anode of the diode D and the first capacitor C r1 Connect the cathode of diode D to the second capacitor C r2 connect.

[0072] exist Figure 2 In the circuit shown, the anode of the diode D is connected to the first capacitor C at the motor control circuit end. r1 Connect the cathode of diode D to the second capacitor C at the air conditioning control circuit end r1 connect.

[0073] In this embodiment, when there are multiple diodes, the multiple diodes are respectively connected in series to the positive electrode and / or the negative electrode of the power bus.

[0074] It can be understood that when there are multiple diodes, the diodes are connected in series to the positive electrode and / or negative electrode of the power bus between the two bus capacitors, and the positive and negative electrode connection directions of the diodes can be determined according to actual usage. That is, multiple diodes can be connected in series to the positive electrode of the power bus between the two bus capacitors, or multiple diodes can be connected in series to the negative electrode of the power bus between the two bus capacitors, or multiple diodes can be connected in series to the positive electrode and negative electrode of the power bus between the two bus capacitors, respectively.

[0075] This embodiment provides a harmonic suppression circuit, which generates a capacitance effect by connecting at least one diode between the motor control circuit and the motor control circuit, changes the loop resonance point, and makes the loop between the motor control circuit and the motor control circuit not resonate at the operating frequency of the vehicle control system, suppresses the loop current between the motor control circuit and the motor control circuit, solves the technical problem of how to suppress the loop current in the vehicle control system, ensures the safety of the motor control circuit and the components in the motor control circuit, and improves the safety of the vehicle control system. In addition, since the internal resistance of the diode is small, the heat dissipation difficulty is small, compared with the harmonic suppression achieved by connecting inductors or capacitors in series, there is no need for heat dissipation, and the cost is low, which improves the economy of the harmonic suppression circuit.

[0076] Embodiment 2

[0077] Based on the same technical concept, this embodiment proposes a harmonic suppression device, which may include:

[0078] Such as the harmonic suppression circuit mentioned above.

[0079] It should be noted that the specific structure of the harmonic suppression circuit in this embodiment refers to the above-mentioned embodiment 1. Since this embodiment adopts all the technical solutions of the above-mentioned embodiment 1, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiment 1, which will not be described one by one here.

[0080] Embodiment 3

[0081] Reference Figure 1 , Figure 1 This is a connection diagram of the first embodiment of the vehicle control system provided by the utility model. Based on the same technical concept, this embodiment proposes a vehicle control system, which may include:

[0082] Motor control circuit and air conditioning control circuit;

[0083] A harmonic suppression circuit as described above is connected between the motor control circuit and the air conditioning control circuit.

[0084] It should be noted that the specific structure of the harmonic suppression circuit in this embodiment refers to the above-mentioned embodiment 1. Since this embodiment adopts all the technical solutions of the above-mentioned embodiment 1, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiment 1, which will not be described one by one here.

[0085] As an implementation, the motor control circuit includes a first power module, and the air conditioning control circuit includes a second power module;

[0086] The first power module is connected to the power battery and the power motor respectively, and is used to work according to the received motor control signal to drive the power motor;

[0087] The second power module is connected to the power battery and the air-conditioning motor respectively, and is used to work according to the received air-conditioning control signal to drive the air-conditioning motor.

[0088] In this embodiment, the specific structures of the first power module and the second power module refer to the above-mentioned embodiment 1, and the motor control signal and the air conditioning control signal can be output to the first power module and the second power module correspondingly by the vehicle control unit in the vehicle control system.

[0089] The above description is only an optional embodiment of the present application, and does not limit the patent scope of the present application. All equivalent structural changes made based on the concept of the present application and the contents of the present application description and drawings, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A harmonic suppression circuit, characterized in that: Applied to a vehicle control system, the vehicle control system includes a motor control circuit and an air conditioning control circuit, and the harmonic suppression circuit includes: At least one diode is connected between the motor control circuit and the air conditioning control circuit, and is used to generate a capacitive effect to change the loop resonance point between the motor control circuit and the air conditioning control circuit to suppress the loop current between the motor control circuit and the air conditioning control circuit.

2. The harmonic suppression circuit according to claim 1, characterized in that: At least one of the diodes is connected in series to a power bus between the motor control circuit and the air conditioning control circuit.

3. The harmonic suppression circuit according to claim 2, characterized in that: The vehicle-mounted control system further includes two bus capacitors, one of the two bus capacitors is connected to the power bus at the motor control circuit end, and the other bus capacitor other than the one of the two bus capacitors is connected to the power bus at the air conditioning control circuit end; At least one of the diodes is connected in series to the power bus between the two bus capacitors.

4. The harmonic suppression circuit according to claim 2, characterized in that: The number of the diode is one, and the diode is connected in series to the positive electrode or the negative electrode of the power bus.

5. The harmonic suppression circuit according to claim 2, characterized in that: There are multiple diodes, and the multiple diodes are respectively connected in series to the positive electrode and / or the negative electrode of the power bus.

6. The harmonic suppression circuit according to claim 3, characterized in that: The two bus capacitors include a first capacitor C r1 and the second capacitor C r2 ; The first capacitor C r1 One end of the first capacitor C is connected to the positive electrode of the power bus at the motor control circuit end, and the first capacitor C r1 The other end is connected to the negative pole of the power bus at the motor control circuit end; The first capacitor C r2 One end of the first capacitor C is connected to the positive electrode of the power bus at the air conditioning control circuit end, and the first capacitor C r2 The other end is connected to the negative pole of the power bus at the air conditioning control circuit end.

7. The harmonic suppression circuit according to claim 6, characterized in that: The at least one diode comprises a diode D; The anode of the diode D and the first capacitor C r1 The cathode of the diode D is connected to the second capacitor C r2 connect.

8. A harmonic suppression device, characterized in that: The harmonic suppression device comprises: A harmonic suppression circuit as claimed in any one of claims 1 to 7.

9. A vehicle-mounted control system, characterized in that: The vehicle-mounted control system comprises: Motor control circuit and air conditioning control circuit; A harmonic suppression circuit as claimed in any one of claims 1 to 7 connected between the motor control circuit and the air conditioning control circuit.

10. The vehicle-mounted control system according to claim 9, characterized in that: The motor control circuit includes a first power module, and the air conditioning control circuit includes a second power module; The first power module is connected to the power battery and the power motor respectively, and is used to work according to the received motor control signal to drive the power motor; The second power module is connected to the power battery and the air-conditioning motor respectively, and is used to work according to the received air-conditioning control signal to drive the air-conditioning motor.

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