Signal processing device of electric power steering system and electric power steering system

Abstract

The utility model relates to the technical field of electric power steering, and provides a signal processing device of an electric power steering system and the electric power steering system. The signal processing device comprises a Darlington tube, the input end of which is used for being connected with an electromagnetic sensor of the electric power steering system; the first photoelectric conversion module comprises a first light-emitting element, a light transmission device and a first photosensitive element, the first light-emitting element is connected with the output end of the Darlington tube, the input end of the light transmission device is arranged in the illumination range of the first light-emitting element, and the first photosensitive element is arranged in the illumination range of the output end of the light transmission device; the input end of the amplifying circuit is connected with the first photosensitive element, and the output end is connected with a controller of the electric power steering system. Analog signals of the electromagnetic sensor are amplified and converted into optical signals to be transmitted to the controller, the problems of transmission delay and signal distortion in a digital coding mode are solved, electromagnetic interference is not prone to occurring, and the requirement of automobile electrification for high electromagnetic interference performance of components is met.

Description

TECHNICAL FIELD

[0001] The utility model relates to electric power steering technical field, concretely relates to signal processing device and electric power steering system of electric power steering system. BACKGROUND

[0002] At present, the data transmission between electromagnetic sensor and controller in electric power steering system is completed by digital coding mode, after the analog signal of electromagnetic change collected by electromagnetic sensor, the transmission to the controller after the digital chip coding arrangement.

[0003] The current mode has the following shortcomings:

[0004] After the analog signal is coded, the resolution is limited by the communication protocol and the clock frequency of the conversion chip, which can easily cause signal distortion;

[0005] A certain clock is consumed in the digital signal conversion process, causing signal transmission delay;

[0006] In the case of increasing demand for automobile electrification, the digital coding mode is easily affected by electromagnetic interference.

[0007] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the utility model, and therefore can include information that does not constitute prior art known to those skilled in the art. UTILITY MODEL CONTENT

[0008] Therefore, the utility model provides a kind of signal processing device and electric power steering system of electric power steering system, analog signal of electromagnetic sensor of electric power steering system can be converted into optical signal transmission to controller, overcome the problems of signal distortion, transmission delay and easily affected by electromagnetic interference caused by digital coding mode.

[0009] One aspect of the utility model provides a kind of signal processing device of electric power steering system, comprising: darlington tube, the input end of the darlington tube is used to connect the electromagnetic sensor of electric power steering system;First photoelectric conversion module, including first light emitting element, light transmission device and first photosensitive element, the first light emitting element is connected the output end of the darlington tube, the input end of the light transmission device is arranged in the light illumination range of the first light emitting element, the first photosensitive element is arranged in the light illumination range of the output end of the light transmission device;Amplification circuit, the input end of the amplification circuit is connected the first photosensitive element, the output end of the amplification circuit is used to connect the controller of electric power steering system.

[0010] The analog signal output by the electromagnetic sensor is relatively weak, and the Darlington tube can amplify the weak analog signal of the electromagnetic sensor to be accurately perceived by the first photoelectric conversion module. Through the first photoelectric conversion module, the amplified analog signal after the Darlington tube is accurately perceived and converted into an optical signal for efficient transmission to the amplification circuit. Further, the electrical signal output by the first photosensitive element is amplified and processed by the amplification circuit, and the electrical signal clearly and accurately representing the analog signal of the electromagnetic sensor is efficiently transmitted to the controller.

[0011] Therefore, the signal processing device of the utility model, through converting the analog signal of the electromagnetic sensor into an optical signal for transmission to the controller, solves the problems of transmission delay and signal distortion in the digital coding mode, and is not susceptible to electromagnetic interference, and meets the demand of high electromagnetic interference performance of components for automobile electrification.

[0012] In some embodiments, the first light emitting element is a light emitting diode, and the positive electrode of the first light emitting element is connected to the power supply end and the negative electrode is connected to the output end of the Darlington tube.

[0013] In this way, the weak analog signal is amplified and converted into a continuously changing current by the Darlington tube, which drives the first light emitting element to emit light signals of different light intensities onto the optical transmission device.

[0014] In some embodiments, the output end of the Darlington tube is also connected to the positive electrode of a freewheeling diode, and the negative electrode of the freewheeling diode is connected to the power supply end.

[0015] The freewheeling diode functions as a freewheeling device to protect the Darlington tube from breakdown.

[0016] In some embodiments, the first light emitting element and the input end of the optical transmission device are packaged in the same chip unit, and / or the output end of the optical transmission device and the first photosensitive element are packaged in the same chip unit.

[0017] By packaging the first light emitting element and the input end / output end of the optical transmission device and the first photosensitive element in the same chip unit, stable and accurate transmission of the optical signal is ensured, and loss is reduced.

[0018] In some embodiments, the amplification circuit includes an operational amplifier, two input ends of the operational amplifier are respectively connected to two ends of the first photosensitive element, and a pull-up resistor is connected to the power supply end and the output end of the operational amplifier.

[0019] The operational amplifier amplifies the potential difference generated at two ends of the first photosensitive element, accurately collects the electrical signal change caused by the change of the analog signal of the electromagnetic sensor, and amplifies the collected electrical signal, so that the electrical signal output to the controller is clear and accurate.

[0020] In some embodiments, the signal processing device further comprises: a second photoelectric conversion module comprising a second light emitting element and a second photosensitive element, the second photosensitive element being arranged within the light irradiation range of the second light emitting element, and the second photosensitive element being used for connecting the controller; and a triode, a control end of the triode being connected to an output end of the operational amplifier, and the second light emitting element being connected in series with the triode.

[0021] The output end of the operational amplifier is connected to the control end of the triode to control the working state of the triode, thereby controlling the electrical signal output by the second photoelectric conversion module to the controller. When the triode is turned on, the second light emitting element emits light, and the second photosensitive element outputs a high-level signal; when the triode is turned off, the second light emitting element does not emit light, and the second photosensitive element outputs a low-level signal.

[0022] In some embodiments, a first current limiting resistor is connected in series between the second light emitting element and the triode; and / or, a second current limiting resistor is connected in series with the second photosensitive element, and a node of the second photosensitive element and the second current limiting resistor is used for connecting the controller.

[0023] The first current limiting resistor and the second current limiting resistor are respectively used for current limiting protection in the corresponding loop.

[0024] In some embodiments, the second light emitting element and the second photosensitive element are packaged in the same chip unit.

[0025] In this way, the stable and accurate transmission of optical signals between the second light emitting element and the second photosensitive element is ensured, and the loss is reduced.

[0026] In some embodiments, the optical transmission device is an optical fiber.

[0027] The optical fiber has the characteristics of high anti-interference, high transmission speed and high reliability, and can accurately and efficiently realize optical signal transmission.

[0028] Another aspect of the utility model provides a kind of electric power assisted steering system, the electric power assisted steering system is configured with the signal processing device as described in any of the above embodiments, and the signal processing device is connected between electromagnetic sensor and controller of the electric power assisted steering system.

[0029] The electric power assisted steering system configured with the signal processing device can amplify the relatively weak analog signal output by the electromagnetic sensor and convert the analog signal into an optical signal to be transmitted to the controller, solve the problems of transmission delay and signal distortion in the digital coding mode, and is not susceptible to electromagnetic interference, and meets the demand of high electromagnetic interference performance of components for automobile electrification.

[0030] The beneficial effects of the utility model compared with the prior art at least include:

[0031] The signal processing device amplifies the weak analog signal of the electromagnetic sensor to the first photoelectric conversion module through the Darlington tube; the first photoelectric module accurately perceives the analog signal amplified by the Darlington tube and converts the analog signal into an optical signal to be efficiently transmitted to the amplification circuit; the electrical signal of the electromagnetic sensor is efficiently transmitted to the controller after the electrical signal output by the first photosensitive element is amplified and processed by the amplification circuit. Thus, the signal processing device of the utility model converts the analog signal of the electromagnetic sensor into an optical signal to be transmitted to the controller, solves the problems of transmission delay and signal distortion in the digital coding mode, is not susceptible to electromagnetic interference, and meets the demand of high electromagnetic interference performance of components for automobile electrification.

[0032] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and cannot limit the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0033] The drawings incorporated into the specification and forming a part thereof show, illustrate the embodiments in accordance with the utility model, and together with the specification serve to explain the principle of the utility model. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0034] Figure 1 The circuit module schematic diagram of the signal processing device in the embodiment of the utility model is shown;

[0035] Figure 2 The circuit structure schematic diagram of the optical signal conversion and emission part of the signal processing device in the embodiment of the utility model is shown;

[0036] Figure 3 The circuit structure schematic diagram of the optical signal receiving and processing part of the signal processing device in the embodiment of the utility model is shown. DETAILED DESCRIPTION

[0037] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the implementations set forth herein. Rather, these implementations are provided as non-limiting examples, so that this disclosure will fully convey the scope of the application to those skilled in the art.

[0038] The accompanying drawings are included to provide a further understanding of the application, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0039] The terms "first", "second", and similar terms do not denote any order, quantity, or importance, but are used to identify different components. Also, in the description of the application, when a device is said to be "connected" to another device, this includes not only the case of direct connection, but also the case of indirect connection through other elements.

[0040] It should be noted that the features of the embodiments of the application and the features of different embodiments can be combined with each other without conflict.

[0041] Figure 1 The circuit module of the signal processing device is shown in FIG. 1, and the signal processing device provided by the embodiment of the application comprises: Figure 1 The signal processing device provided by the embodiment of the application comprises:

[0042] The input end of the Darlington tube 100 is used to connect the electromagnetic sensor of the electric power steering system.

[0043] The first photoelectric conversion module 200 comprises a first light emitting element 110, a light transmission device 120, and a first light sensitive element 130. The first light emitting element 110 is connected to the output end of the Darlington tube 100. The input end 120a of the light transmission device 120 is arranged within the light range of the first light emitting element 110. The first light sensitive element 130 is arranged within the light range of the output end 120b of the light transmission device 120.

[0044] The input end of the amplification circuit 300 is connected to the first light sensitive element 130. The output end of the amplification circuit 300 is used to connect the controller of the electric power steering system.

[0045] The analog signal output by the electromagnetic sensor is relatively weak, and the weak analog signal of the electromagnetic sensor can be amplified to be accurately perceived by the first photoelectric conversion module 200 through the Darlington tube 100. The Darlington tube 100 can include two triodes in series, and can amplify very small signals, and the amplification factor is the product of the amplification factors of the two triodes. The weak analog signal of the electromagnetic sensor is amplified by the Darlington tube 100 to a high multiple, and is converted into a varying current to be provided to the first photoelectric conversion module 200.

[0046] The analog signal amplified by the Darlington tube 100 is accurately perceived by the first photoelectric conversion module 200, and is converted into an optical signal and transmitted to the amplification circuit 300. The first light-emitting element 110 is used to perceive the varying current output by the Darlington tube 100 and emit light signals with different light intensities. The optical transmission device 120 is used to transmit the light signals, so that the signal processing device is arranged between the electromagnetic sensor and the controller of the electric power steering system. The optical transmission device 120 has high transmission speed, high reliability and strong anti-interference performance. The first light-sensitive element 130 perceives the light signal transmitted by the optical transmission device 120 and converts it into an electrical signal transmitted to the amplification circuit 300.

[0047] Further, the electrical signal output by the first light-sensitive element 130 is amplified and processed by the amplification circuit 300, and the electrical signal accurately representing the analog signal of the electromagnetic sensor is efficiently transmitted to the controller.

[0048] Therefore, the signal processing device of the utility model converts the analog signal of the electromagnetic sensor into an optical signal transmitted to the controller, solves the problems of transmission delay and signal distortion of the digital coding mode, and is not easy to be interfered by electromagnetic interference, and meets the needs of high electromagnetic interference performance of components in automobile electrification.

[0049] The specific connection method of the Darlington tube 100 can be set as needed. For example, the Darlington tube 100 can be formed as an NPN compound transistor composed of two NPN transistors, wherein: the base of the first NPN transistor is used as the input end of the Darlington tube 100, the emitter of the first NPN transistor is connected to the base of the second NPN transistor, the emitter of the second NPN transistor can be grounded, and the collector of the first NPN transistor is connected to the collector of the second NPN transistor as the output end of the Darlington tube 100.

[0050] Figure 2 The circuit structure of the optical signal conversion and emission part of the signal processing device is shown, and the combination of Figure 1 and Figure 2As shown, in some embodiments, a Darlington transistor array integrated circuit UI can be used in the circuit, which has seven groups of Darlington transistors, and one group of Darlington transistors can be selected to connect the electromagnetic sensor of the electric power steering system and the first photoelectric conversion module 200 according to specific application, for example, the Darlington transistor 100 with pin 1 as input IN and pin 16 as output is selected.

[0051] Continuing to combine Figure 1 and Figure 2 As shown, in some embodiments, the first light-emitting element 110 is a light-emitting diode LED1, the anode of the light-emitting diode LED1 is connected to the power supply end Vcc, and the cathode is connected to the output end of the Darlington transistor 100.

[0052] In this way, the weak analog signal is amplified and converted into a continuously changing current by the Darlington transistor 100, which drives the light-emitting diode LED1 to emit light signals of different light intensities to the input end 120a of the light transmission device 120.

[0053] In some embodiments, the output end of the Darlington transistor 100 is also connected to the anode of the freewheeling diode D1, and the cathode of the freewheeling diode D1 is connected to the power supply end Vcc.

[0054] The freewheeling diode D1 plays a freewheeling role and can protect the Darlington transistor 100 from breakdown.

[0055] In some embodiments, the light-emitting diode LED1 and the input end 120a of the light transmission device 120 are packaged in a chip unit U2. In this way, the stable and accurate transmission of the light signal between the light-emitting diode LED1 and the light transmission device 120 is ensured, and the loss is reduced.

[0056] Figure 3 The circuit structure of the light signal receiving and processing part of the signal processing device is shown, combining Figure 1 and Figure 3 As shown, in some embodiments, the first light-sensitive element 130 can be a light-sensitive diode D2, but not limited thereto. Further, the output end 120b of the light transmission device 120 and the light-sensitive diode D2 can be packaged in a chip unit U3. In this way, the stable and accurate transmission of the light signal between the light transmission device 120 and the light-sensitive diode D2 is ensured, and the loss is reduced.

[0057] Continuing to combine Figure 1 and Figure 3 As shown, in some embodiments, the amplification circuit 300 includes an operational amplifier U4, two input ends of the operational amplifier U4 are respectively connected to two ends of the light-sensitive diode D2; and a pull-up resistor R1 connected to the power supply end Vcc and the output end of the operational amplifier U4.

[0058] The operational amplifier U4 amplifies the potential difference generated at both ends of the photodiode D2, accurately collects the electrical signal change caused by the change of the analog signal of the electromagnetic sensor, and amplifies the collected electrical signal to make the electrical signal output to the controller clear and accurate. The pull-up resistor R1 is used to stabilize the output of the operational amplifier U4 and avoid oscillation.

[0059] In some embodiments, the signal processing device further comprises a second photoelectric conversion module including a second light emitting element LED2 and a second light sensitive element Q2, the second light sensitive element Q2 is arranged within the light range of the second light emitting element LED2, and the second light sensitive element Q2 is used to connect the controller; a triode Q1, the control end of the triode Q1 is connected to the output end of the operational amplifier U4, and the second light emitting element LED2 is connected in series with the triode Q1.

[0060] The output end of the operational amplifier U4 is connected to the control end of the triode Q1 to control the working state of the triode Q1, and further control the electrical signal output to the controller by the second photoelectric conversion module. When the triode Q1 is turned on, the second light emitting element LED2 emits light, and the second light sensitive element Q2 outputs a high-level signal; when the triode Q1 is cut off, the second light emitting element LED2 does not emit light, and the second light sensitive element Q2 outputs a low-level signal.

[0061] Specifically, as shown in Figures 1 to 3 The triode Q1 is, for example, an NPN transistor. When the optical transmission device 120 outputs an optical signal, the photodiode D2 is turned on, a potential difference is generated at both ends of the photodiode D2, the operational amplifier U4 outputs a high level, the triode Q1 is turned on, and the current flows from the power supply end Vcc through the second light emitting element LED2 and the triode Q1 to the ground. The second light sensitive element Q2 works in the conductive state by sensing the light signal emitted by the second light emitting element LED2, and the output end OUT of the signal processing device outputs a high level. When the optical transmission device 120 does not transmit an optical signal to the photodiode D2, the photodiode D2 is cut off, no potential difference is generated at both ends of the photodiode D2, the operational amplifier U4 outputs a low level, the triode Q1 works in the cut-off state, the second light emitting element LED2 does not work at this time, the second light sensitive element Q2 is in the cut-off state, and the output end OUT outputs a low level.

[0062] In the practical application of the electric power steering system, the analog signal of the electromagnetic sensor continuously changes. When the analog signal decreases, the current flowing through the light-emitting diode LED1 decreases, the light-emitting intensity of the light-emitting diode LED1 weakens, the light signal received by the light transmission device 120 and transmitted to the photodiode D2 weakens, the potential difference between the two ends of the photodiode D2 decreases, the level output by the operational amplifier U4 decreases, the transistor Q1 works in the amplification region, the current flowing through the second light-emitting element LED2 weakens, the sensing current of the second photodiode Q2 decreases, and the output voltage of the output end OUT decreases. When the analog signal increases, the current flowing through the light-emitting diode LED1 increases, the light-emitting intensity of the light-emitting diode LED1 strengthens, the light signal received by the light transmission device 120 and transmitted to the photodiode D2 strengthens, the potential difference between the two ends of the photodiode D2 increases, the level output by the operational amplifier U4 increases, the transistor Q1 works in the amplification region, the current flowing through the second light-emitting element LED2 strengthens, the sensing current of the second photodiode Q2 increases, and the output voltage of the output end OUT increases.

[0063] In some embodiments, the second light-emitting element LED2 and the transistor Q1 are connected in series with a first current-limiting resistor R2; and / or, the second photodiode Q2 is connected in series with a second current-limiting resistor R3, and a node of the second photodiode Q2 and the second current-limiting resistor R3 is used for connecting the controller.

[0064] The first current-limiting resistor R2 and the second current-limiting resistor R3 are respectively used for playing a current-limiting protection role in the corresponding loop.

[0065] In some embodiments, the second light-emitting element LED2 and the second photodiode Q2 are packaged in the same chip unit U5. In this way, the stable and accurate transmission of the light signal between the second light-emitting element LED2 and the second photodiode Q2 is ensured, and the loss is reduced.

[0066] In some embodiments, the second light-emitting element LED2 can be a light-emitting diode, and the second photodiode Q2 can be a phototransistor, but not limited thereto.

[0067] In some embodiments, the light transmission device 120 is an optical fiber. The optical fiber has the characteristics of high anti-interference, high transmission speed and high reliability, and can accurately and efficiently realize the transmission of the light signal.

[0068] The utility model embodiment further provides an electric power steering system, be provided with the signal processing device as described in any of the above embodiments, the signal processing device is connected between the electromagnetic sensor and the controller of the electric power steering system, wherein the electromagnetic sensor can be an electromagnetic torque sensor, an electromagnetic angle sensor, etc.

[0069] The electric power steering system configured with the signal processing device can amplify the relatively weak analog signal output by the electromagnetic sensor and convert the analog signal into an optical signal to be transmitted to the controller, solves the problems of transmission delay and signal distortion in the digital coding mode, and is not susceptible to electromagnetic interference, and meets the demand of high electromagnetic interference performance of components for automobile electrification.

[0070] The above is a further detailed description of the utility model in combination with specific preferred embodiments, and cannot be deemed as limiting the specific implementation of the utility model to these descriptions. For ordinary skilled persons in the technical field to which the utility model belongs, some simple deductions or replacements can be made without departing from the concept of the utility model, and all of them shall be deemed as falling within the protection scope of the utility model.

Claims

1. A signal processing device for an electric power steering system, characterized in that: include: A Darlington tube, wherein the input end of the Darlington tube is used to connect to an electromagnetic sensor of an electric power steering system; A first photoelectric conversion module includes a first light-emitting element, a light transmission device, and a first photosensitive element, wherein the first light-emitting element is connected to the output end of the Darlington tube, the input end of the light transmission device is arranged within the illumination range of the first light-emitting element, and the first photosensitive element is arranged within the illumination range of the output end of the light transmission device; an amplifier circuit, wherein an input end of the amplifier circuit is connected to the first photosensitive element, and an output end of the amplifier circuit is used to be connected to a controller of the electric power steering system.

2. The signal processing device according to claim 1, wherein The first light-emitting element is a light-emitting diode, the positive electrode of the first light-emitting element is connected to the power supply end, and the negative electrode is connected to the output end of the Darlington tube.

3. The signal processing device according to claim 1, wherein The output end of the Darlington tube is also connected to the positive electrode of the freewheeling diode, and the negative electrode of the freewheeling diode is connected to the power supply end.

4. The signal processing device according to claim 1, wherein The first light-emitting element and the input end of the light transmission device are packaged in the same chip unit; and / or The output end of the optical transmission device and the first photosensor are packaged in the same chip unit.

5. The signal processing device according to claim 1, wherein The amplifying circuit comprises: an operational amplifier, wherein two input terminals of the operational amplifier are respectively connected to two terminals of the first photosensitive element; The pull-up resistor is connected to the power supply terminal and the output terminal of the operational amplifier.

6. The signal processing device according to claim 5, wherein Also includes: A second photoelectric conversion module includes a second light-emitting element and a second photosensitive element, wherein the second photosensitive element is arranged within the illumination range of the second light-emitting element and is used to connect to the controller; A transistor, wherein the control end of the transistor is connected to the output end of the operational amplifier, and the second light-emitting element is connected in series with the transistor.

7. The signal processing device according to claim 6, wherein A first current-limiting resistor is connected in series between the second light-emitting element and the transistor; And / or, the second photosensitive element is connected in series with a second current-limiting resistor, and a series node between the second photosensitive element and the second current-limiting resistor is used to connect to the controller.

8. The signal processing device according to claim 6, wherein The second light emitting element and the second photosensor element are packaged in the same chip unit.

9. The signal processing device according to any one of claims 1 to 8, wherein: The optical transmission device is an optical fiber.

10. An electric power steering system, characterized in that: The electric power steering system is equipped with a signal processing device according to any one of claims 1 to 9, and the signal processing device is connected between an electromagnetic sensor and a controller of the electric power steering system.

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