Air-cooled vehicle-mounted driving motor controller
Technical Field
The invention relates to the technical field of vehicle control, in particular to an air-cooled vehicle-mounted driving motor controller.
Background
Along with the weight reduction and cost pressure of automobiles, the size of a driving motor controller is made small, the power density is high and the cost is low under the premise of ensuring the performance. The motor controller is provided with a power component, a large amount of heat can be generated in the working process, and if the heat cannot be effectively dissipated, the service life of the product is influenced, and even potential safety hazards exist. In the running process of the automobile, in order to avoid overheat of the controller of the vehicle-mounted driving motor, the real-time temperature of the controller needs to be controlled. And meanwhile, the requirements of the maximum performance of the vehicle are met. But at present, a technical scheme capable of controlling the temperature of a vehicle-mounted driving motor controller is lacking.
Chinese patent CN103204072a, publication date 2013, 7 and 17, discloses a vehicle-mounted controller, which comprises a rectifying power module, an inverting power module and a control circuit, wherein the rectifying power module, the inverting power module and the power battery are all connected in parallel, the rectifying power module, the inverting power module and the power battery are connected through a bus, the rectifying power module is connected with the generator, the inverting power module is connected with the driving motor, and the control circuit is respectively and independently connected with the rectifying power module and the inverting power module. The technical scheme is that a generator controller and a driving motor controller are designed into a rectifying power module and an inverting power module, the two modules are organically integrated and connected into a whole, and are controlled by a common control circuit, and the invention can be used as a component for direct loading after optimized integration. However, the technical scheme cannot control the temperature of the vehicle-mounted driving motor controller and cannot effectively guarantee the temperature.
Disclosure of Invention
The invention aims to solve the technical problem that a vehicle-mounted driving motor controller with high-efficiency heat dissipation and a temperature control function is lacking at present. An air-cooled vehicle-mounted driving motor controller is provided, which can improve heat dissipation efficiency and control temperature more effectively.
In order to solve the technical problems, the air-cooled vehicle-mounted driving motor controller comprises a radiator and a control unit arranged on the radiator, wherein the control unit comprises a driving plate, a plurality of conductive columns and a plurality of igbt single tubes arranged on the driving plate, a film capacitor, a temperature sensor, a current sensor and an MCU, the radiator is provided with an upper bridge arm and a lower bridge arm, the film capacitor and the conductive columns are correspondingly arranged between the upper bridge arm and the lower bridge arm, two rows of the igbt single tubes are symmetrically arranged and correspond to the upper bridge arm and the lower bridge arm respectively, the igbt single tubes are connected with the driving end of the vehicle-mounted motor through the conductive columns, the temperature sensor detects the current temperature T of the radiator, the current sensor detects the driving current I of the vehicle-mounted motor, the temperature sensor and the current sensor are connected with the MCU, and the MCU runs a temperature control program, predicts the temperature Tt of the radiator according to the current temperature T and the driving current I, and predicts the predicted temperature Tt and generates a driving permission duration according to the predicted temperature Tt.
Preferably, when the MCU calculates the predicted temperature Tt, the following steps are performed:
the MCU periodically reads the current temperature T of the radiator and the driving current I of the vehicle-mounted motor;
The MCU calculates Tt=T (1+k1I-k 2T), wherein k1 and k2 are preset constant coefficients;
the calculated Tt is the predicted radiator temperature Tt after the time t.
Preferably, when the MCU calculates the predicted temperature Tt, the following steps are further performed:
The MCU controls the driving current I to be instantaneously increased to a preset driving current Im, and the driving current I is recovered after the driving current I lasts for a preset time period delta t;
respectively detecting the current temperature values of the radiator before and after the driving current is increased, and recording the current temperature values as T1 and T2;
When the driving current I is in an increasing trend, the MCU calculates k3= (T2-T1)/T0, where T0 is a preset constant value, and then calculates tt=t (1+k1k3i-k2×k3×t);
when the driving current I is in a decreasing trend, the MCU calculates k3=t0/(T2-T1), and then calculates tt=t (1+k1k3i—k2 k3×t).
Preferably, the method of obtaining the preset driving current Im includes:
Under the laboratory condition, gradually increasing the driving current I from a preset value according to a preset step length, and simultaneously detecting the acceleration generated by the vehicle;
and keeping the vehicle acceleration below a preset threshold value, wherein the maximum value obtained by the driving current I is used as a preset driving current Im.
Preferably, the method for obtaining the preset time period Δt includes:
setting a driving current to Im under laboratory conditions, and detecting a speed variation value generated by a vehicle;
and when the speed change value reaches a preset threshold value, the duration is used as a preset duration delta t.
Preferably, the radiator also comprises a pressing strip and ceramic heat conducting fins, wherein each igbt single tube is respectively pressed and connected on the radiator through the corresponding pressing strip, and the ceramic heat conducting fins are arranged between the radiator and the igbt single tubes;
the heat radiator also comprises a thin film capacitor heat radiation plate, and the contact surface of the thin film capacitor heat radiation plate and the radiator is provided with heat conduction silicone grease.
Preferably, the driving board is a six-layer board, and the conductive columns include an anode conductive column, a cathode conductive column, a U-phase conductive column, a V-phase conductive column and a W-phase conductive column which are respectively and fixedly conducted with the driving board.
Preferably, the solar cell further comprises a heat conducting block and an insulating heat conducting pad, wherein the heat radiator is arranged below the installation position of the positive electrode conductive column and the negative electrode conductive column, and the insulating heat conducting pad is arranged above the heat conducting block.
Preferably, the heat-conducting fixing glue is further included, and the heat-conducting fixing glue is paved at the upper and lower positions of the igbt single-tube pins.
Preferably, the surface of the igbt single tube is stuck with graphite sheets.
Preferably, the bus input and three-phase output ends of the control unit are provided with simple quick-plug mounting connectors.
Preferably, the radiator is a 6063 aluminum profile radiator.
Preferably, the heat conducting block is a heat conducting aluminum block.
The invention has the beneficial technical effects that the effect of improving the heat dissipation efficiency of the film capacitor, the conductive column and the igbt single tube is realized through the upper bridge arm and the lower bridge arm, the temperature control is realized through the temperature control program, the overheat condition of the vehicle-mounted driving motor controller can be effectively avoided, the normal operation of a vehicle is ensured, the driving current is increased in a short time to force the vehicle-mounted driving motor controller to generate heat, the real-time heat dissipation efficiency of the vehicle-mounted driving motor controller can be reflected by detecting the change value of the temperature after the duration of the preset time, the temperature of the radiator is predicted more effectively, the maximum allowable value of the current driving current is calculated, the safety of the vehicle-mounted driving motor controller is further ensured, and the volume of the driving motor controller is reduced, the power density is increased and the cost is reduced by redesigning the whole structure of the driving motor controller.
Other features and advantages of the present invention will be disclosed in the following detailed description of the invention and the accompanying drawings.
Drawings
The invention is further described with reference to the accompanying drawings:
fig. 1 is a schematic structural diagram of a vehicle-mounted driving motor controller according to an embodiment of the present invention.
Fig. 2 is a flowchart illustrating a method for calculating a predicted temperature Tt according to an embodiment of the present invention.
Fig. 3 is a flowchart illustrating a method for calculating a predicted temperature Tt more accurately according to an embodiment of the present invention.
Fig. 4 is a side view of a vehicle-mounted driving motor controller according to an embodiment of the present invention.
Fig. 5 is an exploded view of a vehicle-mounted driving motor controller according to an embodiment of the present invention.
Fig. 6 is a partial view of the top of a heat sink in accordance with an embodiment of the present invention.
Fig. 7 is a partial view of a side portion of a heat sink in accordance with an embodiment of the present invention.
Fig. 8 is a schematic structural diagram of a thin film capacitor according to an embodiment of the invention.
Wherein, 1, an upper cover plate, 2, a terminal seat, 3, an upper shell, 4, a simple quick-plug mounting joint, 5, a control board, 6, a conductive column, 7, a driving board, 8, igbt single tubes, 9, a radiator, 91, an upper bridge arm, 92, a lower bridge arm, 10 parts of ceramic heat conducting sheets, 11 parts of film capacitors, 12 parts of heat conducting blocks, 13 parts of pressing strips, 14 parts of insulating heat conducting pads, 15 parts of film capacitor heat radiating plates, 16 parts of heat conducting fixing glue, 17 parts of graphite sheets, 18 parts of heat conducting silicone grease.
Detailed Description
The technical solutions of the embodiments of the present invention will be explained and illustrated below with reference to the drawings of the embodiments of the present invention, but the following embodiments are only preferred embodiments of the present invention, and not all embodiments. Based on the examples in the implementation manner, other examples obtained by a person skilled in the art without making creative efforts fall within the protection scope of the present invention.
In the following description, directional or positional relationships such as the terms "inner", "outer", "upper", "lower", "left", "right", etc., are presented for convenience in describing the embodiments and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the invention.
Referring to fig. 1, an air-cooled vehicle-mounted driving motor controller comprises a radiator 9 and a control unit mounted on the radiator 9, wherein the control unit comprises a driving plate 7, a plurality of conductive posts 6 and a plurality of igbt single tubes 8 mounted on the driving plate 7, a film capacitor 11, a temperature sensor, a current sensor and an MCU, the radiator 9 is provided with an upper bridge arm 91 and a lower bridge arm 92, the film capacitor 11 and the conductive posts 6 are correspondingly arranged at mounting positions between the upper bridge arm 91 and the lower bridge arm 92, the igbt single tubes 8 are symmetrically provided with two rows of columns which are respectively corresponding to the upper bridge arm 91 and the lower bridge arm 92, the igbt single tubes 8 are connected with the driving end of the vehicle-mounted motor through the conductive posts 6, the temperature sensor detects the current temperature T of the radiator 9, the current sensor detects the driving current I of the vehicle-mounted motor, the temperature sensor and the current sensor are connected with the MCU, the MCU runs a temperature control program, and the temperature control program predicts the temperature Tt according to the current T and the driving current I, and the radiator 9 after predicting the time T predicts the temperature Tt and generates a driving current allowable upper limit value according to the predicted temperature Tt.
Referring to fig. 2, when the mcu calculates the predicted temperature Tt, the following steps are performed:
Step A01), the MCU periodically reads the current temperature T of the radiator 9 and the driving current I of the vehicle-mounted motor;
Step a 02) the MCU calculates tt=t (1+k1i—k2×t), where k1 and k2 are preset constant coefficients;
Step a 03) calculates the calculated Tt as the predicted temperature Tt of the radiator 9 after the time period t.
The predicted temperature Tt is related to the present temperature T and the present drive current I, i.e., tt=t+a1 (I-I0), where a1 is a coefficient and I0 is a reference current. The reference current is not constant, but the suitable reference current value is not the same for different current temperatures T. I.e. i0=a2×t, a2 being a coefficient. Thus, a calculation formula of tt=t (1+k1 i-k 2T) is obtained for calculating the predicted temperature Tt. The effect of improving the heat dissipation efficiency of the thin film capacitor 11, the conductive columns 6 and igbt single tubes 8 is achieved through the upper bridge arm 91 and the lower bridge arm 92, the temperature is controlled through a temperature control program, the overheat condition of the vehicle-mounted driving motor controller can be effectively avoided, and the normal operation of the vehicle is guaranteed.
On the other hand, the present embodiment further provides a more accurate scheme for calculating the predicted temperature Tt, and referring to fig. 3, when the mcu calculates the predicted temperature Tt, the following steps are further performed:
Step B01), the MCU controls the driving current I to be instantaneously increased to a preset driving current Im, and the driving current I is restored after the preset time period delta t is continued;
step B02) detecting the current temperature values of the radiator 9 before and after the driving current is increased, and recording the current temperature values as T1 and T2;
Step B03), when the driving current I is in an increasing trend, the MCU calculates k3= (T2-T1)/T0, wherein T0 is a preset constant value, and then calculates tt=t (1+k1k3i-k2 k3);
Step B04) when the driving current I is in a decreasing trend, the MCU calculates k3=t0/(T2-T1), and then calculates tt=t (1+k1×k3×i-k2×k3×t).
The temperature value of the radiator 9 is related not only to the present temperature T and the drive current I, but also to the current heat dissipation situation. The real-time heat dissipation conditions of the vehicle are variable and difficult to predict accurately. Therefore, the present embodiment observes the temperature change of the radiator 9 under real-time conditions by actively increasing the driving current I. And thus, the real-time heat dissipation condition is tested once, and the real-time heat dissipation condition is characterized by the test result, namely k 3. When the driving current I is in an increasing trend, the temperature T will rise, where k3= (T2-T1)/T0, and when the driving current I is in a decreasing trend, the temperature T will fall, where k3=t0/(T2-T1). The driving current is increased in a short time, the vehicle-mounted driving motor controller is forced to generate heat, and the change value of the temperature is detected after the preset time duration is continued, so that the real-time heat dissipation efficiency of the vehicle-mounted driving motor controller can be reflected, the temperature of the radiator 9 is predicted more effectively, the maximum allowable value of the current driving current is calculated, and the safety of the vehicle-mounted driving motor controller is further ensured
Under laboratory conditions, gradually increasing the driving current I according to a preset step length from a preset value, and simultaneously detecting acceleration generated by a vehicle;
The vehicle acceleration is kept below a preset threshold, and the maximum value taken by the driving current I is taken as a preset driving current Im.
Setting a driving current to be Im under laboratory conditions, and detecting a speed change value generated by a vehicle at the same time;
when the speed change value reaches a preset threshold value, the duration is used as a preset duration delta t.
The embodiment also comprises pressing strips 13 and ceramic heat conducting fins 10, wherein each igbt single tube 8 is respectively pressed on the radiator 9 through the corresponding pressing strips 13, and the ceramic heat conducting fins 10 are arranged between the radiator 9 and the igbt single tubes 8. The structure can reduce thermal resistance, and has large heat dissipation area and good heat dissipation effect.
The embodiment also comprises a thin-film capacitor radiating plate 15, and the contact surface of the thin-film capacitor radiating plate 15 and the radiator 9 is provided with heat-conducting silicone grease 18. More specifically, the thin film capacitor 11 is fixed in the middle of the radiator 9, an aluminum plate is embedded at the bottom of the thin film capacitor 11, the back surface of the aluminum plate is coated with heat conducting silicone grease 18, namely a thin film capacitor radiating plate 15, and heat of the thin film capacitor 11 is conducted through the plate to cause the radiator 9.
The igbt single tube 8 pin of this embodiment is welded with the drive plate 7, the drive plate 7 is six-layer board, the conductive column 6 includes positive pole conductive column, negative pole conductive column, U looks conductive column, V looks conductive column, W looks conductive column and drive plate 7 respectively through bolt fastening switch on, this overall arrangement mode flow equalizing effect is good.
The embodiment further comprises a heat conducting block 12 and an insulating heat conducting pad 14, wherein the heat conducting block 12 (aluminum block) is arranged at the position of the radiator 9 below the installation position of the positive electrode conductive column and the negative electrode conductive column, the insulating heat conducting pad 14 is arranged above the heat conducting block 12, and heat of the driving plate 7 can be conducted to the radiator 9 through the heat conducting block 12, so that the overall heat dissipation effect is improved.
The embodiment further comprises a heat conduction fixing adhesive 16, the heat conduction fixing adhesive 16 is paved at the upper and lower positions of the pins of the igbt single tube 8, heat can be conducted to the radiator 9, graphite sheets 17 are stuck on the surface of the molding shell of the igbt single tube 8, and the graphite sheets 17 are extended and stuck to the two sides of the radiator 9, so that the igbt single tube 8 achieves a double-sided heat dissipation effect, and the overall performance is improved.
Through redesigning the integral structure of the driving motor controller, the volume of the driving motor controller is reduced, the power density is increased and the cost is reduced.
It should be noted that the control unit part in the product further includes components (shown in the drawings) such as an upper cover plate 1, a terminal base 2, an upper housing 3, a control board 5, etc., which are all in the prior art, and therefore will not be described in detail.
The bus input and three-phase output end of the control unit of the embodiment adopts a simple quick-plug mounting connector 4, and the connector is convenient to mount and low in cost.
While the invention has been described in terms of embodiments, it will be appreciated by those skilled in the art that the invention is not limited thereto but rather includes the drawings and the description of the embodiments above. Any modifications which do not depart from the functional and structural principles of the present invention are intended to be included within the scope of the appended claims.