Rotary transformer excitation circuit

Abstract

The utility model relates to the technical field of power electronics, and discloses a rotary transformer excitation circuit. The circuit comprises at least one power integrated operational amplifier unit and a direct current bias voltage unit, the power integrated operational amplifier unit comprises a signal input end, a bias voltage input end and a signal output end; the DC bias voltage unit is connected with the bias voltage input end. According to the application, the power integrated operational amplifier unit is arranged to carry out power amplification on the received excitation sinusoidal signal based on the direct current bias voltage and then output the excitation sinusoidal signal to the external main control chip, and due to the adoption of the power integrated operational amplifier design circuit, the circuit structure is simplified, the total number of devices in the circuit is reduced, and control blind spots are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power electronics, and particularly relates to a rotary transformer excitation circuit. BACKGROUND

[0002] With the continuous development of power electronics technology, the rotary transformer excitation circuit is used for current and voltage control of power equipment to ensure stable operation of the power system.

[0003] However, the existing rotary transformer excitation circuit is obtained by amplifying the voltage of an excitation sinusoidal signal and then connecting the amplified current to the rotary excitation signal through a push-pull circuit. At present, voltage amplification and current amplification need to be separately realized by setting a complex circuit structure, which makes the circuit structure design more complex and requires more devices, resulting in too many control blind spots in the entire circuit and being not conducive to subsequent control. CONTENT OF THE UTILITY MODEL

[0004] Therefore, the present application provides a rotary transformer excitation circuit to solve the problem of too many control blind spots in the circuit design of the existing rotary transformer excitation circuit.

[0005] The first aspect of the present application provides a rotary transformer excitation circuit, comprising: at least one power integrated operational amplifier unit and a direct current bias voltage unit; the power integrated operational amplifier unit is a device having at least a power push-pull circuit and an operational amplifier circuit, which comprises a signal input end, a bias voltage input end and a signal output end; the direct current bias voltage unit is connected with the bias voltage input end and is used for outputting a direct current bias voltage; the signal input end is used for receiving an input excitation sinusoidal signal; and the signal output end is used for outputting a rotary transformer excitation signal to an external master control chip.

[0006] In a feasible implementation, the power push-pull circuit is composed of at least two complementary transistors, and the operational amplifier circuit is composed of an amplifier; the input pins of the amplifier are respectively connected with the signal input end and the bias voltage input end, and the at least two complementary transistors are arranged between the output pin of the amplifier and the signal output end.

[0007] In a feasible implementation, the power integrated operational amplifier unit further integrates a detection circuit, which is connected with the signal output end, the power push-pull circuit and the operational amplifier circuit; the power integrated operational amplifier unit further comprises a detection output end connected with the detection circuit, which is used for outputting a corresponding fault signal when the power integrated operational amplifier unit abnormally operates.

[0008] In an implementation, the detection circuit comprises: an overcurrent detection circuit connected to the signal output terminal, configured to collect an output current of the power integrated operational amplifier unit and output an overcurrent detection signal; and an overtemperature detection circuit connected to the power push-pull circuit and the operational amplifier circuit, configured to collect a working temperature of the power integrated operational amplifier unit and output an overtemperature detection signal.

[0009] In an implementation, the rotary transformer excitation circuit further comprises a first pull-up resistor connected to an overcurrent detection output terminal of the overcurrent detection circuit.

[0010] In an implementation, the rotary transformer excitation circuit further comprises a second pull-up resistor connected to an overtemperature detection output terminal of the overtemperature detection circuit.

[0011] In an implementation, the DC bias voltage unit comprises a voltage dividing circuit and a first filter circuit; the voltage dividing circuit comprises at least two resistors connected in series, and the bias voltage input terminal is connected to a midpoint of the voltage dividing circuit, configured to provide a DC bias voltage; and the first filter circuit comprises at least one capacitor, and each capacitor is connected between the midpoint and the ground, configured to filter the DC bias voltage.

[0012] In an implementation, the rotary transformer excitation circuit further comprises an interface protection unit connected to the signal output terminal; the interface protection unit comprises an EMI filter circuit, an EMS protection TVS circuit and a common mode inductor; the EMI filter circuit and the EMS protection TVS circuit are connected in parallel between two input terminals of the common mode inductor.

[0013] In an implementation, the rotary transformer excitation circuit further comprises a power supply unit configured to provide a stable working voltage for each circuit / unit of the rotary transformer excitation circuit.

[0014] In an implementation, the rotary transformer excitation circuit further comprises an input resistor and a filter capacitor connected in series, and a common terminal of the input resistor and the filter capacitor is connected to the signal input terminal, configured to filter an excitation sinusoidal signal transmitted through the input resistor.

[0015] In the technical scheme provided in the application, the circuit comprises at least one power integrated operational amplifier unit and a DC bias voltage unit; the power integrated operational amplifier unit comprises a signal input terminal, a bias voltage input terminal and a signal output terminal; and the DC bias voltage unit is connected to the bias voltage input terminal. In the application, the power integrated operational amplifier unit is configured to amplify a received excitation sinusoidal signal based on a DC bias voltage and output the amplified signal to an external master control chip. Since the power integrated operational amplifier is used to design the circuit, the circuit structure is simplified, the total number of devices in the circuit is reduced, and the control blind spot is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 A first schematic diagram of a rotary transformer excitation circuit provided for an embodiment of the present application;

[0017] Figure 2 A second schematic diagram of a rotary transformer excitation circuit provided for an embodiment of the present application;

[0018] Figure 3 A circuit schematic diagram of a power supply unit and a detection unit provided for an embodiment of the present application;

[0019] Figure 4 A circuit schematic diagram of a rotary transformer excitation circuit provided for an embodiment of the present application;

[0020] Figure 5 A circuit schematic diagram of a rotary transformer excitation circuit provided for an embodiment of the present application;

[0021] Figure 6 A circuit schematic diagram of a rotary transformer excitation circuit provided for an embodiment of the present application; DETAILED DESCRIPTION

[0022] The present application provides a rotary transformer excitation circuit, by setting a power integrated operational amplifier unit integrated with push-pull triode and operational amplifier, power amplifying and outputting the excitation sinusoidal signal, to replace the whole circuit of the existing push-pull circuit and operational amplifier, thereby simplifying the overall circuit structure of the rotary transformer excitation circuit, and setting an overcurrent and overtemperature detection circuit to realize overcurrent and overtemperature detection of the output current and working temperature in the circuit, and controlling the power integrated operational amplifier based on the feedback result of the detection. Such design not only simplifies the circuit structure, reduces the use of devices, thereby reducing the control blind spot in the circuit, but also realizes the detection of the abnormality of the circuit, and improves the safety of the whole system.

[0023] The terms "first", "second", "third", "fourth" and the like in the description and claims of the present application and above-described drawings (if any) are used to distinguish between similar objects, not necessarily in an ordinal, serial, or chronological sequence. It is to be understood that data used with such terms could, in appropriate cases, be interchanged, out of the contexts indicated, with data concerning a similar object, so that the examples that are described herein, for instance, can be implemented, in other than the order shown and / or described. Also, the terms "comprise", "comprising", "including", "comprises", "comprising", "including" and "contain" and / or "containing", are intended to cover a non-exclusive inclusion, such that a process, method, system, product, or apparatus that comprises, includes, contains or contains one or more steps or units, does not necessarily consist of the one or more steps or units, but can include other steps or units not expressly listed or inherent to such process, method, system, product, or apparatus.

[0024] As Figure 1As shown in the embodiment of this application, a resolver excitation circuit is provided. The circuit includes at least one power integrated operational amplifier unit 110 and a DC bias voltage unit 120. The at least one power integrated operational amplifier unit 110 is arranged in parallel, that is, the output terminals of each power integrated operational amplifier unit 110 are connected together. The input terminal of the power integrated operational amplifier unit 110 is connected to the DC bias voltage unit 120. The power integrated operational amplifier unit 110 amplifies the excitation sinusoidal signal based on the DC bias voltage unit 120 and outputs it.

[0025] It should be noted that the power integrated operational amplifier unit 110 is a device that integrates push-pull output function and operational amplifier function. That is to say, the power integrated operational amplifier unit 110 here is an integrated circuit that combines the logic devices inside the chip to form a push-pull transistor and an operational amplifier. For example, by connecting the logic devices that implement the transistor function inside the chip to form a push-pull transistor circuit, and by connecting the logic devices that implement the amplifier function to form an operational amplifier circuit.

[0026] The DC bias voltage unit 120 can be a voltage divider circuit structure or a voltage source. It mainly provides bias voltage to the power integrated operational amplifier 110. The bias voltage is amplified according to the voltage and current to provide an excitation sine signal, so as to output a resolver excitation signal to drive the external chip to work.

[0027] In this embodiment, the power integrated operational amplifier 110 includes a signal input terminal 111, a bias voltage input terminal 112, and a signal output terminal 113;

[0028] The DC bias voltage unit 120 is connected to the bias voltage input terminal 112 and is used to output DC bias voltage;

[0029] The signal input terminal 111 is used to receive the input excitation sinusoidal signal;

[0030] The signal output terminal 113 is used to output the resolver excitation signal to the external main control chip.

[0031] In this embodiment, the power integrated operational amplifier unit 110 can also be a device that simultaneously has push-pull output function, operational amplifier function and detection function, which correspond to the power push-pull circuit 114, operational amplifier circuit 115 and detection circuit 116, respectively.

[0032] Understandably, the power push-pull circuit 114 is located at the output of the operational amplifier circuit 115. The input of the operational amplifier circuit 115 is connected to the signal input terminal 111 and the signal output terminal 113. The detection circuit 116 is connected to the detection input terminal 111 and is used to output a fault signal when the power integrated operational amplifier 110 is detected to be faulty.

[0033] The power push-pull circuit 114 is composed of at least two complementary transistors, and the operational amplifier circuit 115 is composed of an amplifier; input pins of the amplifier are connected with the signal input end 111 and the bias voltage input end 112 respectively, and the at least two complementary transistors are arranged between an output pin of the amplifier and the signal output end 113.

[0034] Specifically, the power integrated operational amplifier unit 110 further comprises a detection output end 117 connected with the detection circuit 116, for outputting a corresponding fault signal when the power integrated operational amplifier unit 110 appears an abnormality; specifically, the detection output end 117 comprises two kinds of detection output ports, one is an overcurrent detection output end, and the other is an overtemperature detection output end; correspondingly, two overcurrent and overtemperature detection circuits are also arranged on the detection circuit 116, for detecting whether the temperature is overtemperature, and detecting whether the currents of the HS signal and the LS signal are overcurrent.

[0035] In another embodiment, as shown in Figure 2 The detection circuit 116 comprises: an overcurrent detection circuit 1161 connected with the signal output end 113, for collecting an output current of the power integrated operational amplifier unit 110 and outputting an overcurrent detection signal; and an overtemperature detection circuit 1162 connected with the power push-pull circuit 114 and the operational amplifier circuit 115, for collecting a working temperature of the power integrated operational amplifier unit 110 and outputting an overtemperature detection signal.

[0036] It can be understood that the rotary variable reluctance magnet circuit further comprises a first pull-up resistor and a second pull-up resistor; the first pull-up resistor is connected with an overcurrent detection output end of the overcurrent detection circuit, and the second pull-up resistor is connected with an overtemperature detection output end of the overtemperature detection circuit; when it is detected that the output current of the power integrated operational amplifier unit 110 exceeds a preset overcurrent threshold, an overcurrent detection signal is outputted to an external master control chip through the overcurrent detection output end; when it is detected that the working temperature of the power integrated operational amplifier unit 110 exceeds a preset overtemperature threshold, an overtemperature detection signal is outputted to the external master control chip through the overtemperature detection output end.

[0037] In the embodiment, the rotary variable reluctance magnet circuit further comprises a power supply unit 130, for providing stable working voltages for each circuit / unit of the rotary variable reluctance magnet circuit.

[0038] As shown in Figure 3As shown, the power supply unit 130 is composed of a plurality of capacitors in parallel, for filtering out high-frequency noise interference of the input voltage signal and outputting to the detection circuit 116, wherein the overcurrent detection output end of the detection circuit 116 includes two, which are HS signal overcurrent detection end A1 and LS signal overcurrent detection end A2, wherein the HS signal collected by the HS signal overcurrent detection end A1 is input into the power integrated operational amplifier unit 110, and an overcurrent point of 400mA is set inside the power integrated operational amplifier unit 110, and a high level is output when the current is lower than 400mA, and a low level is output to the DSP TM detection pin of the external main control chip when overcurrent occurs, for detecting and judging whether overcurrent occurs in this path amplification, and a first resistor R2 of 10K is applied to enhance the pull-up function and increase the anti-interference ability; the LS signal collected by the LS signal overcurrent detection end A2 is input into the power integrated operational amplifier unit 110, and an overcurrent point of 400mA is set inside the power integrated operational amplifier unit 110, and a high level is output when the current is lower than 400mA, and a low level is output to the DSP TM detection pin of the external main control chip when overcurrent occurs, for detecting and judging whether overcurrent occurs in this path amplification, and a first resistor R3 of 10K is applied to enhance the pull-up function and increase the anti-interference ability.

[0039] For the over-temperature detection output end, that is, the chip over-temperature detection pin B in the figure, the temperature signal collected by the chip over-temperature detection pin B is input into the power integrated operational amplifier unit 110, and an over-temperature point of 75℃ is set inside the power integrated operational amplifier unit 110, and a high level is output when the temperature is lower than 75℃, and a low level is output to the DSP TM detection pin of the external main control detection chip when over-temperature occurs, for detecting and judging whether over-temperature occurs in the chip, and a second resistor R4 of 10K is applied to enhance the pull-up function and increase the anti-interference ability.

[0040] In the embodiment, the DC bias voltage unit 120 is provided mainly to avoid waveform distortion after the rear-stage amplification, and specifically includes a voltage dividing circuit 121 and a first filter circuit 122; the output end of the voltage dividing circuit 121 is connected with the bias voltage input end 112, for providing a DC bias voltage; and the first filter circuit 122 is connected with the bias voltage input end 112, for filtering the DC bias voltage. The voltage dividing circuit 121 includes at least two resistors connected in series, and the bias voltage input end 113 is arranged at a middle point of the voltage dividing circuit 121; the first filter circuit 122 includes at least one capacitor, and each capacitor is arranged between the middle point and the ground. As shown in the figure, Figure 4 As shown, the DC bias voltage unit 120 generally selects 1 / 2VCC, and is generally designed by using the same resistors R7 and R12 in series and a capacitor C10, and the C10 is used for DC bias filtering.

[0041] In the embodiment, the rotating variable excitation circuit further comprises an interface protection unit 140 connected with the signal output end 113, for improving the anti-interference ability and electromagnetic compatibility of the circuit.

[0042] It should be noted that the interface protection unit 140 comprises an EMI filter circuit, an EMS protection TVS circuit and a common mode inductor; the EMI filter circuit and the EMS protection TVS circuit are connected in parallel between two input ends of the common mode inductor. As shown in Figure 4 In the embodiment, the EMI filter circuit is composed of capacitors C20, C24 and C25 connected in series, and C20 and C25 are grounded, and C24 is connected in parallel between the two input ends of the common mode inductor; the EMS protection TVS circuit is composed of two ordinary diodes and two TVS diodes connected in reverse series, wherein one ordinary diode and one TVS diode are connected in reverse series to form a group, and the two groups are connected in series and grounded; the common mode inductor is L1 in the figure, and the two output ends are connected with an external chip to output the rotating variable excitation signal.

[0043] In the embodiment, the rotating variable excitation circuit further comprises a second filter circuit and a feedback circuit, wherein the second filter circuit is arranged on the signal input end 111 of the power integrated operational amplifier unit 110, and the feedback circuit is arranged between the signal input end 111 and the signal output end 113 of the power integrated operational amplifier unit 110. As shown in Figure 4 The second filter circuit is composed of an input resistor R15 10K and a filter capacitor C17 1nF; the feedback circuit is composed of a resistor and a capacitor connected in parallel to achieve a corresponding multiple of amplification gain, and in the figure, the resistor is R18 30K, the amplification gain G=4, and the pole filter capacitor C23 100pF is achieved.

[0044] In another embodiment, the rotating variable excitation circuit further comprises a third filter circuit arranged between the output end of the power integrated operational amplifier unit 110 and the interface protection unit 140, which is specifically implemented by a ceramic capacitor, which has the characteristics of passing alternating current and resisting direct current, and is used to filter the direct current bias after voltage amplification and current amplification, so as to avoid the oxidation and corrosion of the excitation signal line by the direct current source in the case of rotating variable insulation failure.

[0045] In the embodiment, the rotating variable excitation circuit further comprises an input resistor and a filter capacitor connected in series, and the common end of the input resistor and the filter capacitor is connected with the signal input end 111, for filtering the excitation sinusoidal signal transmitted through the input resistor.

[0046] In the embodiment, the resolver excitation circuit further comprises an excitation sinusoidal signal generating unit 150, the output end of which is connected with the signal input end 111, and used for outputting an excitation sinusoidal signal to the power integrated operational amplifier unit 110. The excitation sinusoidal signal generating unit 150 is realized by two operational amplifiers connected in series, and the specific circuit implementation is as shown in Figure 5 .

[0047] In another embodiment, the resolver excitation circuit is not limited to the way of using two power integrated operational amplifier units 110 to realize the differential excitation output of the resolver excitation signal, and is also applicable to the single-ended common-mode excitation driving output. As shown in Figure 6 , the circuit of the single-ended common-mode mode is half less, and then through appropriate change of the corresponding amplification gain, after current amplification, current limiting, and direct current capacitor output, it is also applicable. As for the selection of the power integrated operational amplifier unit 110, it is not limited to ALM2402F operational amplifier, and is also applicable to the operational amplifier with the same function.

[0048] Through the implementation of the resolver excitation circuit provided above, since the power integrated operational amplifier is directly used for the excitation signal power amplification output, the push-pull triode and the operational amplifier are integrated inside the device, and the voltage amplification and the current amplification are realized at the same time, and the device usage is reduced by 95%.

[0049] Further, the detection circuit is also arranged in the power integrated operational amplifier unit, which is used for detecting whether the circuit is overcurrent or overvoltage, realizing that the resolver excitation circuit has an abnormal shutdown detection pin, and can respectively feed back the detection of whether the two-way amplification output is overcurrent, and detect whether it is in the safe temperature working range; realizing the diagnosis of the working abnormality of the resolver position detection end excitation signal, and increasing the safety of the automobile electronic control system.

[0050] Finally, it should be noted that: the above embodiments are only specific embodiments of the present application, which are used to illustrate the technical solutions of the present application, but not to limit them, and the protection scope of the present application is not limited to this. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily think of changes to the technical solutions recorded in the foregoing embodiments within the technical range disclosed by the present application, or make equivalent replacement to some technical features; and these modifications, changes or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and all should be covered in the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A resolver excitation circuit, characterized in that, include: At least one power integrated operational amplifier unit and a DC bias voltage unit; The power integrated operational amplifier unit is a device that has at least a power push-pull circuit and an operational amplifier circuit, and includes a signal input terminal, a bias voltage input terminal, and a signal output terminal; The DC bias voltage unit is connected to the bias voltage input terminal and is used to output DC bias voltage; The signal input terminal is used to receive the input excitation sinusoidal signal; The signal output terminal is used to output the resolver excitation signal to the external main control chip.

2. The resolver excitation circuit according to claim 1, characterized in that, The power push-pull circuit consists of at least two complementary transistors, and the operation and discharge circuit consists of an amplifier. The input pins of the amplifier are connected to the signal input terminal and the bias voltage input terminal, respectively, and the at least two complementary transistors are disposed between the output pins of the amplifier and the signal output terminal.

3. The resolver excitation circuit according to claim 1, characterized in that, The power integrated operational amplifier unit also integrates a detection circuit, which is connected to the signal output terminal, the power push-pull circuit, and the operational amplifier circuit; The power integrated operational amplifier unit also includes a detection output terminal connected to the detection circuit, used to output a corresponding fault signal when the power integrated operational amplifier unit malfunctions.

4. The resolver excitation circuit according to claim 3, characterized in that, The detection circuit includes: An overcurrent detection circuit, which is connected to the signal output terminal, is used to collect the output current and output overcurrent detection signal of the power integrated operational amplifier unit; An over-temperature detection circuit, which is connected to the power push-pull circuit and the operational amplifier circuit, is used to collect the operating temperature of the power integrated operational amplifier unit and output an over-temperature detection signal.

5. The resolver excitation circuit according to claim 4, characterized in that, The resolver excitation circuit also includes a first pull-up resistor connected to the overcurrent detection output terminal of the overcurrent detection circuit.

6. The resolver excitation circuit according to claim 5, characterized in that, The resolver excitation circuit also includes a second pull-up resistor connected to the over-temperature detection output terminal of the over-temperature detection circuit.

7. The resolver excitation circuit according to claim 1, characterized in that, The DC bias voltage unit includes a voltage divider circuit and a first filter circuit; The voltage divider circuit includes at least two resistors connected in series, and the bias voltage input terminal is connected at the midpoint of the voltage divider circuit to provide a DC bias voltage. The first filter circuit includes at least one capacitor, each of which is disposed between the neutral point and ground, for filtering the DC bias voltage.

8. The resolver excitation circuit according to claim 1, characterized in that, The resolver excitation circuit further includes: an interface protection unit connected to the signal output terminal; The interface protection unit includes an EMI filter circuit, an EMS protection TVS circuit, and a common-mode inductor; the EMI filter circuit and the EMS protection TVS circuit are connected in parallel between the two input terminals of the common-mode inductor.

9. The resolver excitation circuit according to claim 1, characterized in that, The resolver excitation circuit further includes a power supply unit, which provides a stable operating voltage for each circuit / unit of the resolver excitation circuit.

10. The resolver excitation circuit according to claim 1, characterized in that, The resolver excitation circuit further includes an input resistor and a filter capacitor connected in series. The common terminal of the input resistor and the filter capacitor is connected to the signal input terminal to filter the excitation sinusoidal signal transmitted through the input resistor.

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