An electromagnetic retarder control system

Abstract

The present invention belongs to the technical field of electromagnetic retarders, and discloses an electromagnetic retarder control system, including a single-chip microcomputer, an excitation coil control circuit, an excitation coil drive circuit and an overcurrent detection circuit, wherein the pulse width modulation signal output end of the single-chip microcomputer is connected to the excitation coil control circuit, the analog-to-digital conversion port of the single-chip microcomputer is connected to the overcurrent detection circuit, the excitation coil drive circuit is connected to the excitation coil, and is used to drive multiple or single excitation coils, and the excitation coil control circuit and the overcurrent detection circuit are respectively connected to the excitation coil drive circuit, and are used to reduce the current of the driven excitation coil to 0A when the current exceeds the limit. The electromagnetic retarder control system of the present invention automatically reduces the current of the drive coil to 0A when the current exceeds the limit, has a protection function for the power tube, has high system reliability, and has a long service life.

Description

Technical Field

[0001] The invention belongs to the technical field of electromagnetic retarders, and in particular relates to an electromagnetic retarder control system. Background Art

[0002] The electromagnetic retarder is a braking device installed on the gearbox, between the transmission shafts or on the drive axle. Its purpose is to slow down the vehicle and prevent unnecessary acceleration. It consists of a stator with several excitation coils built in and a rotor connected to the transmission shaft with a gap between the two.

[0003] At present, the control system of the electromagnetic retarder does not have a power tube over-current protection function. In actual use, it is very easy for the middle section of the excitation coil to be directly grounded due to wear and rupture of the excitation coil, causing the power tube to exceed the current and the temperature to rise suddenly, resulting in the power tube bursting. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an electromagnetic retarder control system to solve the problem that the electromagnetic retarder control system has no power tube overcurrent protection function and is very likely to cause the power tube to explode during use.

[0005] To solve the above technical problems, the present invention is implemented by adopting the following solutions: The present invention provides an electromagnetic retarder control system, comprising a single-chip microcomputer, an excitation coil control circuit, an excitation coil drive circuit and an overcurrent detection circuit, wherein a pulse width modulation signal output end of the single-chip microcomputer is connected to the excitation coil control circuit, an analog-to-digital conversion port of the single-chip microcomputer is connected to the overcurrent detection circuit, the excitation coil drive circuit is connected to the excitation coil and is used to drive multiple or a single excitation coil, and the excitation coil control circuit and the overcurrent detection circuit are both connected to the excitation coil drive circuit and are used to reduce the current of the driven excitation coil to 0A when the current exceeds the limit.

[0006] Optionally, it also includes an energy storage circuit, which includes an energy storage resistor and an energy storage capacitor. One end of the energy storage resistor is connected to one end of the energy storage capacitor, the output end of the excitation coil drive circuit, one end of the excitation coil and the other end of the energy storage resistor are connected, and the other end of the energy storage capacitor is connected to the ground terminal of the battery.

[0007] Optionally, it also includes a freewheeling circuit, which includes an excitation unit freewheeling diode, the cathode of the excitation unit freewheeling diode, the output end of the excitation coil drive circuit and one end of the excitation coil are connected, and the anode of the excitation unit freewheeling diode is connected to the battery ground terminal.

[0008] Optionally, the excitation coil control circuit, the excitation coil drive circuit, the overcurrent detection circuit and the excitation coil are all four groups; Each group of excitation coil control circuits includes an optocoupler, a current limiting resistor, a pull-down resistor, a pull-up resistor and a freewheeling diode, the pulse width modulation signal output end of the single-chip microcomputer is connected to one end of the current limiting resistor, the other end of the current limiting resistor and one end of the pull-down resistor are connected to the first pin of the optocoupler, the second pin of the optocoupler and the other end of the pull-down resistor are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler and the positive electrode of the freewheeling diode are connected to the ground terminal of the battery, the fourth pin of the optocoupler and the negative electrode of the freewheeling diode are connected to one end of the pull-up resistor, and the other end of the pull-up resistor is connected to the positive input voltage of the battery; Each set of excitation coil driving circuits includes a power tube, the third pin of the power tube is connected to the fourth pin of the optocoupler, the fourth and tape automatic combination pins of the power tube are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the power tube are connected to one end of the excitation coil, and the other end of the excitation coil is connected to the ground terminal of the battery; Each overcurrent detection circuit includes a first detection resistor and a second detection resistor. The analog-to-digital conversion port of the microcontroller, one end of the first detection resistor and one end of the second detection resistor are connected, the other end of the first detection resistor is connected to the fifth pin of the power tube, and the other end of the second detection resistor is connected to the ground terminal of the microcontroller.

[0009] Optionally, the excitation coil control circuit, the excitation coil drive circuit and the excitation coil are each in two groups, and the overcurrent detection circuit is in four groups; Each group of excitation coil control circuits includes an optocoupler, a current limiting resistor, a pull-down resistor, a pull-up resistor and a freewheeling diode, the pulse width modulation signal output end of the single-chip microcomputer is connected to one end of the current limiting resistor, the other end of the current limiting resistor and one end of the pull-down resistor are connected to the first pin of the optocoupler, the second pin of the optocoupler and the other end of the pull-down resistor are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler and the positive electrode of the freewheeling diode are connected to the ground terminal of the battery, the fourth pin of the optocoupler and the negative electrode of the freewheeling diode are connected to one end of the pull-up resistor, and the other end of the pull-up resistor is connected to the positive input voltage of the battery; Each set of excitation coil driving circuits includes two power tubes, the third pins of the two power tubes are connected to the fourth pin of the optocoupler, the fourth and tape automatic combination pins of the two power tubes are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the two power tubes are connected to one end of the excitation coil, and the other end of the excitation coil is connected to the ground terminal of the battery; Each overcurrent detection circuit includes a first detection resistor and a second detection resistor. The analog-to-digital conversion port of the microcontroller, one end of the first detection resistor and one end of the second detection resistor are connected, the other end of the first detection resistor is connected to the fifth pin of the power tube, and the other end of the second detection resistor is connected to the ground terminal of the microcontroller.

[0010] Optionally, the excitation coil control circuit, the excitation coil drive circuit and the excitation coil are all one group, and the overcurrent detection circuit is four groups; The excitation coil control circuit includes an optocoupler, a current limiting resistor, a pull-down resistor, a pull-up resistor and a freewheeling diode, the pulse width modulation signal output end of the single-chip microcomputer is connected to one end of the current limiting resistor, the other end of the current limiting resistor and one end of the pull-down resistor are connected to the first pin of the optocoupler, the second pin of the optocoupler and the other end of the pull-down resistor are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler and the positive electrode of the freewheeling diode are connected to the ground terminal of the battery, the fourth pin of the optocoupler and the negative electrode of the freewheeling diode are connected to one end of the pull-up resistor, and the other end of the pull-up resistor is connected to the positive input voltage of the battery; The excitation coil driving circuit includes four power tubes, the third pins of the four power tubes are connected to the fourth pin of the optocoupler, the fourth and tape automatic combination pins of the four power tubes are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the four power tubes are connected to one end of the excitation coil, and the other end of the excitation coil is connected to the ground terminal of the battery; Each overcurrent detection circuit includes a first detection resistor and a second detection resistor. The analog-to-digital conversion port of the microcontroller, one end of the first detection resistor and one end of the second detection resistor are connected, the other end of the first detection resistor is connected to the fifth pin of the power tube, and the other end of the second detection resistor is connected to the ground terminal of the microcontroller.

[0011] Optionally, a conversion circuit is also included, which includes a switching regulator, a first inductor, a second inductor, a first polarity capacitor, a second polarity capacitor, a first capacitor and a second capacitor. The first pin of the switching regulator, the positive electrode of the first polarity capacitor, and one end of the first capacitor are connected to the positive input voltage of the battery, the fifth pin of the switching regulator, the third pin of the switching regulator, the negative electrode of the first polarity capacitor, and the other end of the first capacitor are connected to the ground terminal of the battery, the fourth pin of the switching regulator, one end of the first inductor, the positive electrode of the second polarity capacitor, and one end of the second capacitor are connected to the positive voltage of the microcontroller, the negative electrode of the second polarity capacitor and the other end of the second capacitor are connected to the ground terminal of the microcontroller, and the two ends of the second inductor are respectively connected to the ground terminal of the battery and the ground terminal of the microcontroller.

[0012] The present invention also provides an electromagnetic retarder, wherein the electromagnetic retarder is configured with the electromagnetic retarder control system described above.

[0013] Beneficial Effects

[0014] The present invention connects the excitation coil control circuit, the excitation coil driving circuit and the overcurrent detection circuit through a single chip microcomputer, and can drive multiple / single excitation coils. When the current exceeds the limit, the current of the driving coil is automatically reduced to 0A, which has a protection function for the power tube, has high system reliability and long service life.

[0015] The present invention is provided with an energy storage circuit, which stores a part of the electric energy when the excitation coil is energized so that the voltage value at both ends of the excitation coil will not increase suddenly, and releases a part of the electric energy when the excitation coil is powered off so that the voltage value at both ends of the excitation coil will not decrease suddenly, thereby protecting the circuit.

[0016] The present invention is provided with a freewheeling circuit, which can prevent the self-induced electromotive force (with a very high voltage value) generated by the excitation coil when it is turned off from causing impact on the power tube.

[0017] The present invention realizes the scheme of configuring four / two / single excitation coils for the electromagnetic retarder, meets the diversified configuration requirements of the electromagnetic retarder, and reduces the number of excitation coils and the difficulty of the excitation coil winding process from the scheme of configuring four excitation coils to the scheme of configuring two excitation coils and then to the scheme of configuring a single excitation coil.

[0018] The present invention is provided with a conversion circuit which can convert the positive input voltage of a high-voltage battery into a positive 5V voltage for a single-chip microcomputer in the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a peripheral circuit diagram of a single chip microcomputer in an electromagnetic retarder control system provided by Embodiment 1 of the present invention; Figure 2 is a conversion circuit diagram of an electromagnetic retarder control system provided by Embodiment 1 of the present invention; Figure 3 It is a circuit diagram of a first excitation coil control circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Figure 4 It is a circuit diagram of a first excitation coil driving circuit, a first overcurrent detection circuit, a first energy storage circuit and a first freewheeling circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Figure 5 It is a circuit diagram of a second excitation coil control circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Figure 6 It is a circuit diagram of a second excitation coil driving circuit, a second overcurrent detection circuit, a second energy storage circuit and a second freewheeling circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Figure 7 It is a circuit diagram of a third excitation coil control circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Figure 8 It is a circuit diagram of a third excitation coil driving circuit, a third overcurrent detection circuit, a third energy storage circuit and a third freewheeling circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Fig. 9 It is a circuit diagram of a fourth excitation coil control circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Fig.10 It is a circuit diagram of a fourth excitation coil driving circuit, a fourth overcurrent detection circuit, a fourth energy storage circuit and a fourth freewheeling circuit of a four-excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention; Fig.11 It is a circuit diagram of a fifth excitation coil control circuit of a two-excitation coil solution of an electromagnetic retarder control system provided in Embodiment 1 of the present invention; Fig.12 It is a circuit diagram of a fifth excitation coil driving circuit, a fifth overcurrent detection circuit, a fifth energy storage circuit and a fifth freewheeling circuit of a two-excitation coil solution of an electromagnetic retarder control system provided in Embodiment 1 of the present invention; Fig.13 It is a circuit diagram of a sixth excitation coil control circuit of a two-excitation coil solution of an electromagnetic retarder control system provided in Embodiment 1 of the present invention; Fig.14 It is a circuit diagram of a sixth excitation coil driving circuit, a sixth overcurrent detection circuit, a sixth energy storage circuit and a sixth freewheeling circuit of a two-excitation coil solution of an electromagnetic retarder control system provided in Embodiment 1 of the present invention; Fig.15 It is a circuit diagram of a seventh excitation coil control circuit of a single excitation coil solution of an electromagnetic retarder control system provided in Embodiment 1 of the present invention; Fig.16 It is a circuit diagram of a seventh excitation coil driving circuit, a seventh overcurrent detection circuit, a seventh energy storage circuit and a seventh freewheeling circuit of a single excitation coil solution of an electromagnetic retarder control system provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0021] Example 1

[0022] The present embodiment provides an electromagnetic retarder control system, including a single-chip microcomputer, an excitation coil control circuit, an excitation coil drive circuit and an overcurrent detection circuit, wherein the pulse width modulation signal output terminal of the single-chip microcomputer is connected to the excitation coil control circuit, the analog-to-digital conversion port of the single-chip microcomputer is connected to the overcurrent detection circuit, the excitation coil drive circuit is connected to the excitation coil, and is used to drive multiple or single excitation coils, and the excitation coil control circuit and the overcurrent detection circuit are both connected to the excitation coil drive circuit, and are used to reduce the current of the driven excitation coil to 0A when the current exceeds the limit. The electromagnetic retarder control system is connected to the excitation coil control circuit, the excitation coil drive circuit and the overcurrent detection circuit through the single-chip microcomputer, and can drive multiple / single excitation coils. When the current exceeds the limit, the current of the drive coil is automatically reduced to 0A, and has a protection function for the power tube, and the system has high reliability and long service life.

[0023] like Figure 1 As shown in the figure, the single chip microcomputer adopts the MC9S12XS128MAA microcontroller. Figure 2 As shown, the electromagnetic retarder control system also includes a conversion circuit, which is used to convert the high-voltage battery positive input voltage (+Vin) into a positive 5V voltage (CPU+5V) for the single-chip computer. The conversion circuit includes a switching regulator DY1, an inductor L1, an inductor L2, a polar capacitor C1, a polar capacitor C2, a capacitor C3 and a capacitor C4. The model of the switching regulator DY1 is LM2596S-5.0. The first pin of the switching regulator DY1, the positive electrode of the polar capacitor C1, and one end of the capacitor C3 are connected to the positive input voltage of the battery. The fifth pin of the switching regulator DY1, the third pin of the switching regulator DY1, the negative electrode of the polarity capacitor C1, the other end of the capacitor C3 and the battery ground terminal (Dian-Chi-GND) are connected, the fourth pin of the switching regulator DY1, one end of the inductor L1, the positive electrode of the polarity capacitor C2, one end of the capacitor C4 and the single-chip computer are connected with a positive 5V voltage, the negative electrode of the polarity capacitor C2, the other end of the capacitor C4 and the single-chip computer ground terminal (CPU-GND) are connected, and the two ends of the inductor L2 are respectively connected to the battery ground terminal and the single-chip computer ground terminal.

[0024] like Figures 3 to 10 The four-excitation coil solution is shown. The excitation coil control circuit, excitation coil drive circuit, overcurrent detection circuit and excitation coil are all four groups, as follows: The first excitation coil control circuit includes an optocoupler G5, a current limiting resistor R13, a pull-down resistor R14, a pull-up resistor R15 and a freewheeling diode D5. The first pulse width modulation signal output terminal (CPU-PWM1) of the single-chip microcomputer is connected to one end of the current limiting resistor R13, the other end of the current limiting resistor R13 and one end of the pull-down resistor R14 are connected to the first pin of the optocoupler G5, the second pin of the optocoupler G5 and the other end of the pull-down resistor R14 are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler G5 and the positive electrode of the freewheeling diode D5 are connected to the ground terminal of the battery, the fourth pin of the optocoupler G5, the negative electrode of the freewheeling diode D5 and the pull-up resistor R 15, and the other end of the pull-up resistor R15 is connected to the positive input voltage of the battery; the first excitation coil driving circuit includes a power tube U1, the third pin of the power tube U1 is connected to the fourth pin of the optocoupler G5, the fourth and tape automatic combination pins (4&Tab pins) of the power tube U1 are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the power tube U1 are connected to one end of the excitation coil XQ1, and the other end of the excitation coil XQ1 is connected to the ground terminal of the battery; the first overcurrent detection circuit includes a detection resistor R25 and a detection resistor R26, a first analog-to-digital conversion port (CPU-PAD1) of the single-chip microcomputer, and a detection resistor R One end of the detection resistor R25 is connected to one end of the detection resistor R26, the other end of the detection resistor R25 is connected to the fifth pin of the power tube U1, and the other end of the detection resistor R26 is connected to the ground terminal of the single-chip computer; in addition, it also includes a first energy storage circuit and a first freewheeling circuit. The first energy storage circuit stores a part of the electric energy when the excitation coil XQ1 is powered on, so that the voltage value at both ends of the excitation coil XQ1 will not increase suddenly, and releases a part of the electric energy when the excitation coil XQ1 is powered off, so that the voltage value at both ends of the excitation coil XQ1 will not decrease suddenly, thereby protecting the circuit; the first freewheeling circuit can prevent the self-inductance electromotive force ( The voltage value is very high) causes an impact on the power tube U1; the first energy storage circuit includes an energy storage resistor R27 and an energy storage capacitor C5, one end of the energy storage resistor R27 is connected to one end of the energy storage capacitor C5, the output end of the excitation coil drive circuit, one end of the excitation coil XQ1 and the other end of the energy storage resistor R27 are connected, and the other end of the energy storage capacitor C5 is connected to the battery ground terminal, the first freewheeling circuit includes an excitation unit freewheeling diode EJG1, the cathode of the excitation unit freewheeling diode EJG1, the output end of the excitation coil drive circuit and one end of the excitation coil XQ1 are connected, and the anode of the excitation unit freewheeling diode EJG1 is connected to the battery ground terminal; The second excitation coil control circuit includes an optocoupler G6, a current limiting resistor R16, a pull-down resistor R17, a pull-up resistor R18 and a freewheeling diode D6. The second pulse width modulation signal output terminal (CPU-PWM2) of the single-chip microcomputer is connected to one end of the current limiting resistor R16, the other end of the current limiting resistor R16 and one end of the pull-down resistor R17 are connected to the first pin of the optocoupler G6, the second pin of the optocoupler G6 and the other end of the pull-down resistor R17 are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler G6 and the positive electrode of the freewheeling diode D6 are connected to the ground terminal of the battery, the fourth pin of the optocoupler G6, the negative electrode of the freewheeling diode D6 and the pull-up resistor R18 are connected to the ground terminal of the battery, and the fourth pin of the optocoupler G6, the negative electrode of the freewheeling diode D6 and the pull-up resistor R18 are connected to the ground terminal of the single-chip microcomputer. The first overcurrent detection circuit comprises a detection resistor R28 and a detection resistor R29, and the second overcurrent detection circuit comprises a detection resistor R28 and a detection resistor R29, a second analog-to-digital conversion port (CPU-PAD2) of the single-chip microcomputer, and one end of the detection resistor R28 is connected to the positive input voltage of the battery. The second overcurrent detection circuit comprises a detection resistor R28 and a detection resistor R29, a second analog-to-digital conversion port (CPU-PAD2) of the single-chip microcomputer, and one end of the detection resistor R28 is connected to the positive input voltage of the battery. The first circuit is connected to the detection resistor R29, and the other end of the detection resistor R28 is connected to the fifth pin of the power tube U2. The other end of the detection resistor R29 is connected to the ground terminal of the single-chip computer. In addition, it also includes a second energy storage circuit and a second freewheeling circuit. The second energy storage circuit stores a part of the electric energy when the excitation coil XQ2 is powered on, so that the voltage value at both ends of the excitation coil XQ2 will not increase suddenly. When the excitation coil XQ2 is powered off and turned off, a part of the electric energy is released, so that the voltage value at both ends of the excitation coil XQ2 will not decrease suddenly, thereby protecting the circuit. The second freewheeling circuit can prevent the self-induced electromotive force (voltage) generated by the excitation coil XQ2 when it is turned off. The value is very high) causes impact on the power tube U2; the second energy storage circuit includes an energy storage resistor R30 and an energy storage capacitor C6, one end of the energy storage resistor R30 is connected to one end of the energy storage capacitor C6, the output end of the excitation coil drive circuit, one end of the excitation coil XQ2 and the other end of the energy storage resistor R30 are connected, and the other end of the energy storage capacitor C6 is connected to the battery ground terminal, and the second freewheeling circuit includes an excitation unit freewheeling diode EJG2, the cathode of the excitation unit freewheeling diode EJG2, the output end of the excitation coil drive circuit and one end of the excitation coil XQ2 are connected, and the anode of the excitation unit freewheeling diode EJG2 is connected to the battery ground terminal; The third excitation coil control circuit includes an optocoupler G7, a current limiting resistor R19, a pull-down resistor R20, a pull-up resistor R21 and a freewheeling diode D7. The third pulse width modulation signal output terminal (CPU-PWM3) of the single-chip microcomputer is connected to one end of the current limiting resistor R19, the other end of the current limiting resistor R19 and one end of the pull-down resistor R20 are connected to the first pin of the optocoupler G7, the second pin of the optocoupler G7 and the other end of the pull-down resistor R20 are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler G7 and the positive electrode of the freewheeling diode D7 are connected to the ground terminal of the battery, the fourth pin of the optocoupler G7, the negative electrode of the freewheeling diode D7 and the pull-up resistor R21 are connected to the ground terminal of the battery, and the third pin of the optocoupler G7 and the negative electrode of the freewheeling diode D7 are connected to the ground terminal of the battery. The third excitation coil driving circuit includes a power tube U3, a third pin of the power tube U3 is connected to the fourth pin of the optical coupler G7, a fourth and a tape automatic combination pin of the power tube U3 are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the power tube U3 are connected to one end of the excitation coil XQ3, and the other end of the excitation coil XQ3 is connected to the ground terminal of the battery; the third overcurrent detection circuit includes a detection resistor R31 and a detection resistor R32, a third analog-to-digital conversion port (CPU-PAD3) of the single-chip microcomputer, one end of the detection resistor R31 The third energy storage circuit is connected to one end of the detection resistor R32, the other end of the detection resistor R31 is connected to the fifth pin of the power tube U3, and the other end of the detection resistor R32 is connected to the ground terminal of the single-chip computer; in addition, it also includes a third energy storage circuit and a third freewheeling circuit. The third energy storage circuit stores a part of the electric energy when the excitation coil XQ3 is powered on, so that the voltage value at both ends of the excitation coil XQ3 will not increase suddenly, and releases a part of the electric energy when the excitation coil XQ3 is powered off and turned off, so that the voltage value at both ends of the excitation coil XQ3 will not decrease suddenly, thereby protecting the circuit; the third freewheeling circuit can prevent the self-induced electromotive force (voltage) generated by the excitation coil XQ3 when it is turned off. The value is very high) causes impact on the power tube U3; the third energy storage circuit includes an energy storage resistor R33 and an energy storage capacitor C7, one end of the energy storage resistor R33 is connected to one end of the energy storage capacitor C7, the output end of the excitation coil drive circuit, one end of the excitation coil XQ3 and the other end of the energy storage resistor R33 are connected, and the other end of the energy storage capacitor C7 is connected to the battery ground terminal, and the third freewheeling circuit includes an excitation unit freewheeling diode EJG3, the cathode of the excitation unit freewheeling diode EJG3, the output end of the excitation coil drive circuit and one end of the excitation coil XQ3 are connected, and the anode of the excitation unit freewheeling diode EJG3 is connected to the battery ground terminal; The fourth excitation coil control circuit includes an optocoupler G8, a current limiting resistor R22, a pull-down resistor R23, a pull-up resistor R24 ​​and a freewheeling diode D8. The fourth pulse width modulation signal output terminal (CPU-PWM4) of the single-chip microcomputer is connected to one end of the current limiting resistor R22, the other end of the current limiting resistor R22, one end of the pull-down resistor R23 and the first pin of the optocoupler G8 are connected, the second pin of the optocoupler G8 and the other end of the pull-down resistor R23 are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler G8 and the positive electrode of the freewheeling diode D8 are connected to the ground terminal of the battery, the fourth pin of the optocoupler G8, the negative electrode of the freewheeling diode D8 and the pull-up resistor are connected to the ground terminal of the battery, and the fourth pin of the optocoupler G8, the negative electrode of the freewheeling diode D8 and the pull-up resistor are connected to the ground terminal of the battery. The fourth excitation coil driving circuit includes a power tube U4, a third pin of the power tube U4 is connected to the fourth pin of the optical coupler G8, a fourth and a tape automatic combination pin of the power tube U4 are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the power tube U4 are connected to one end of the excitation coil XQ4, and the other end of the excitation coil XQ4 is connected to the ground terminal of the battery; the fourth overcurrent detection circuit includes a detection resistor R34 and a detection resistor R35, a fourth analog-to-digital conversion port (CPU-PAD4) of the single-chip microcomputer, and one end of the detection resistor R34 The fourth energy storage circuit is connected to one end of the detection resistor R35, the other end of the detection resistor R34 is connected to the fifth pin of the power tube U4, and the other end of the detection resistor R35 is connected to the ground terminal of the single-chip computer; in addition, it also includes a fourth energy storage circuit and a fourth freewheeling circuit. The fourth energy storage circuit stores a part of the electric energy when the excitation coil XQ4 is powered on, so that the voltage value at both ends of the excitation coil XQ4 will not increase suddenly, and releases a part of the electric energy when the excitation coil XQ4 is powered off and turned off, so that the voltage value at both ends of the excitation coil XQ4 will not decrease suddenly, thereby protecting the circuit; the fourth freewheeling circuit can prevent the self-induced electromotive force (voltage) generated by the excitation coil XQ4 when it is turned off. The value is very high) causes impact on the power tube U4; the fourth energy storage circuit includes an energy storage resistor R36 and an energy storage capacitor C8, one end of the energy storage resistor R36 is connected to one end of the energy storage capacitor C8, the output end of the excitation coil drive circuit, one end of the excitation coil XQ4 and the other end of the energy storage resistor R36 are connected, and the other end of the energy storage capacitor C8 is connected to the battery ground terminal, and the fourth freewheeling circuit includes an excitation unit freewheeling diode EJG4, the cathode of the excitation unit freewheeling diode EJG4, the output end of the excitation coil drive circuit and one end of the excitation coil XQ4 are connected, and the anode of the excitation unit freewheeling diode EJG4 is connected to the battery ground terminal; Among them, the models of power tube U1, power tube U2, power tube U3 and power tube U4 are BTS50085.

[0025] Working principle: The first excitation coil control circuit controls the on / off of the power tube U1: when the first pulse width modulation signal output terminal of the single chip microcomputer is at a low level, the optocoupler G5 is not conducting, and the voltage at the fourth pin of the optocoupler G5 is Uin-1 is high level, then the first excitation coil drive circuit, the first overcurrent detection circuit, the first energy storage circuit and the first freewheeling circuit U in-1 When the first pulse width modulation signal output terminal of the single chip microcomputer is at a high level, the optocoupler G5 is turned on, and the voltage of the fourth pin of the optocoupler G5 is U in-1 is low level, then the first excitation coil drive circuit, the first overcurrent detection circuit, the first energy storage circuit and the first freewheeling circuit U in-1 is low level, the power tube U1 is turned on, the fourth and tape automatic combination pins of the power tube U1 are connected to the first, second, sixth and seventh pins, the excitation coil XQ1 is turned on, and the excitation coil XQ1 generates a magnetic field. When the excitation coil XQ1 is turned on, if the first conduction current I 1 is within the rated current value of the power tube U1, the fourth and tape automatic combination pins of the power tube U1 are connected to the first, second, sixth and seventh pins, and the excitation coil XQ1 is turned on. At this time, the fifth pin IS of the power tube U1 outputs a high level, and the voltage value of the first analog-to-digital conversion port of the single-chip computer is a high level; when the excitation coil XQ1 is turned on, if the first conduction current I 1 exceeds the rated current value of the driving power tube U1, the fourth and tape automatic combination pins of the power tube U1 are disconnected from the first, second, sixth and seventh pins, and the excitation coil XQ1 is energized and cut off. At this time, the fifth pin IS of the power tube U1 outputs a low level, and the voltage value of the first analog-to-digital conversion port of the single-chip microcomputer is a low level. When the first pulse width modulation signal output end of the single-chip microcomputer is at a high level, if the voltage value of the first analog-to-digital conversion port of the single-chip microcomputer is a low level, the single-chip microcomputer MC9S12XS128MAA assigns the first pulse width modulation signal output end to 0, and the power tube U1 is protected from circuit breaker.

[0026] The second excitation coil control circuit controls the on / off of the power tube U2: When the second pulse width modulation signal output terminal of the single chip microcomputer is at a low level, the optocoupler G6 is not conducting, and the voltage at the fourth pin of the optocoupler G6 is U in-2 is high level, then the second excitation coil drive circuit, the second overcurrent detection circuit, the second energy storage circuit and the second freewheeling circuit U in-2 When the second pulse width modulation signal output terminal of the single chip microcomputer is at a high level, the optocoupler G6 is turned on, and the voltage of the fourth pin of the optocoupler G6 isU in-2 is low level, then the second excitation coil drive circuit, the second overcurrent detection circuit, the second energy storage circuit and the second freewheeling circuit U in-2 is low level, the power tube U2 is turned on, the fourth and tape automatic combination pins of the power tube U2 are connected to the first, second, sixth and seventh pins, the excitation coil XQ2 is turned on, and the excitation coil XQ2 generates a magnetic field. When the excitation coil XQ2 is turned on, if the second conduction current I 2 is within the rated current value of the power tube U2, the fourth and tape automatic combination pins of the power tube U2 are connected to the first, second, sixth and seventh pins, the excitation coil XQ2 is turned on, at this time, the 5th pin IS of the power tube U2 outputs a high level, and the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a high level; when the excitation coil XQ2 is turned on, if the second conduction current I 2 exceeds the rated current value of the driving power tube U2, the fourth and automatic tape combination pins of the power tube U2 are disconnected from the first, second, sixth and seventh pins, and the excitation coil XQ2 is powered off. At this time, the fifth pin IS of the power tube U2 outputs a low level, and the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a low level. When the second pulse width modulation signal output end of the single-chip microcomputer is at a high level, if the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a low level, the single-chip microcomputer MC9S12XS128MAA assigns the second pulse width modulation signal output end to 0, and the power tube U2 is protected from circuit breaker.

[0027] The third excitation coil control circuit controls the on / off of the power tube U3: when the third pulse width modulation signal output terminal of the single chip microcomputer is at a low level, the optocoupler G7 is not conducting, and the fourth pin voltage of the optocoupler G7 is U in-3 is high level, then the third excitation coil drive circuit, the third overcurrent detection circuit, the third energy storage circuit and the third freewheeling circuit U in-3 When the third pulse width modulation signal output terminal of the single chip microcomputer is at a high level, the optocoupler G7 is turned on, and the voltage of the fourth pin of the optocoupler G7 is U in-3 is low level, then the third excitation coil drive circuit, the third overcurrent detection circuit, the third energy storage circuit and the third freewheeling circuit U in-3 is low level, the power tube U3 is turned on, the fourth and tape automatic combination pins of the power tube U3 are connected to the first, second, sixth and seventh pins, the excitation coil XQ3 is turned on, and the excitation coil XQ3 generates a magnetic field. When the excitation coil XQ3 is turned on, if the third conduction current I3 is within the rated current value of the power tube U3. The fourth and tape automatic combination pins of the power tube U3 are connected to the first, second, sixth and seventh pins. The excitation coil XQ3 is turned on. At this time, the fifth pin IS of the power tube U3 outputs a high level. The voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a high level. When the excitation coil XQ3 is turned on, if the third conduction current I 3 exceeds the rated current value of the driving power tube U3, the fourth and tape automatic combination pins of the power tube U3 are disconnected from the first, second, sixth and seventh pins, and the excitation coil XQ3 is powered off. At this time, the fifth pin IS of the power tube U3 outputs a low level, and the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a low level. When the third pulse width modulation signal output end of the single-chip microcomputer is at a high level, if the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a low level, the single-chip microcomputer MC9S12XS128MAA assigns the third pulse width modulation signal output end to 0, and the power tube U3 is protected from circuit breaker.

[0028] The fourth excitation coil control circuit controls the on / off of the power tube U4: when the fourth pulse width modulation signal output terminal of the single chip microcomputer is at a low level, the optocoupler G8 is not conducting, and the fourth pin voltage of the optocoupler G8 is U in-4 is high level, then the fourth excitation coil drive circuit, the fourth overcurrent detection circuit, the fourth energy storage circuit and the fourth freewheeling circuit U in-4 When the fourth pulse width modulation signal output terminal of the single chip microcomputer is at a high level, the optical coupler G8 is turned on, and the voltage of the fourth pin of the optical coupler G8 is U in-4 is low level, then the fourth excitation coil drive circuit, the fourth overcurrent detection circuit, the fourth energy storage circuit and the fourth freewheeling circuit U in-4 is low level, the power tube U4 is turned on, the fourth and tape automatic combination pins of the power tube U4 are connected to the first, second, sixth and seventh pins, the excitation coil XQ4 is turned on, and the excitation coil XQ4 generates a magnetic field. When the excitation coil XQ4 is turned on, if the fourth conduction current I 4 is within the rated current value of the power tube U4, the fourth and tape automatic combination pins of the power tube U4 are connected to the first, second, sixth and seventh pins, the excitation coil XQ4 is turned on, at this time, the fifth pin IS of the power tube U4 outputs a high level, and the voltage value of the fourth analog-to-digital conversion port of the single-chip computer is a high level; when the excitation coil XQ4 is turned on, if the fourth conduction current I4 exceeds the rated current value of the driving power tube U4, the fourth and tape automatic combination pins of the power tube U4 are disconnected from the first, second, sixth and seventh pins, and the excitation coil XQ4 is powered off. At this time, the fifth pin IS of the power tube U4 outputs a low level, and the voltage value of the fourth analog-to-digital conversion port of the single-chip microcomputer is a low level. When the fourth pulse width modulation signal output end of the single-chip microcomputer is at a high level, if the voltage value of the fourth analog-to-digital conversion port of the single-chip microcomputer is a low level, the single-chip microcomputer MC9S12XS128MAA assigns the fourth pulse width modulation signal output end to 0, and the power tube U4 is protected from circuit breaker.

[0029] In order to reduce the number of electromagnetic retarder excitation coils and reduce the difficulty of the excitation coil winding process, the following method can be used: Figures 11 to 14 In the two-excitation coil scheme shown, the excitation coil control circuit, the excitation coil drive circuit and the excitation coil are all two groups, and the overcurrent detection circuit is four groups, as follows: The fifth excitation coil control circuit includes an optocoupler G9, a current limiting resistor R37, a pull-down resistor R38, a pull-up resistor R39 and a freewheeling diode D9, a first pulse width modulation signal output terminal of the single-chip microcomputer is connected to one end of the current limiting resistor R37, the other end of the current limiting resistor R37 and one end of the pull-down resistor R38 are connected to the first pin of the optocoupler G9, the second pin of the optocoupler G9 and the other end of the pull-down resistor R38 are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler G9 and the positive electrode of the freewheeling diode D9 are connected to the ground terminal of the battery, the fourth pin of the optocoupler G9 and the negative electrode of the freewheeling diode D9 are connected to one end of the pull-up resistor R39, and the other end of the pull-up resistor R39 is connected to the positive input voltage of the battery; the fifth excitation coil control circuit includes an optocoupler G9, a current limiting resistor R37, a pull-down resistor R38, a pull-up resistor R39, and a first pin of the single-chip microcomputer, a current limiting resistor R37, a pull-down resistor R38, and a first pin of the optocoupler G9, a pull-down resistor R38, and a ground terminal of the single-chip microcomputer, a positive electrode of the freewheeling diode D9 and a battery ground terminal, a negative electrode of the freewheeling diode D9 and one end of the pull-up resistor R39, and a positive input voltage of the battery. The coil driving circuit includes power tube U5 and power tube U6, the third pins of power tube U5 and power tube U6 are connected to the fourth pin of optocoupler G9, the fourth and the tape automatic combination pins of power tube U5 and power tube U6 are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of power tube U5 and power tube U6 are connected to one end of excitation coil XQ5, and the other end of excitation coil XQ5 is connected to the ground terminal of the battery; the fifth overcurrent detection circuit includes detection resistor R43, detection resistor R44, detection resistor R45 and detection resistor R46, the first analog-to-digital conversion port of the single-chip microcomputer, one end of the detection resistor R43 and one end of the detection resistor R44 are connected, and the other end of the detection resistor R43 is connected to the power tube U5 The fifth pin, the other end of the detection resistor R44 is connected to the ground terminal of the single-chip computer, the second analog-to-digital conversion port of the single-chip computer, one end of the detection resistor R45 and one end of the detection resistor R46 are connected, the other end of the detection resistor R45 is connected to the fifth pin of the power tube U6, and the other end of the detection resistor R46 is connected to the ground terminal of the single-chip computer; in addition, it also includes a fifth energy storage circuit and a fifth freewheeling circuit. The fifth energy storage circuit stores a part of the electric energy when the excitation coil XQ5 is powered on, so that the voltage value at both ends of the excitation coil XQ5 will not increase suddenly, and releases a part of the electric energy when the excitation coil XQ5 is powered off, so that the voltage value at both ends of the excitation coil XQ5 will not decrease suddenly, thereby protecting the circuit; the fifth freewheeling circuit can prevent the excitation coil from The self-induced electromotive force (high voltage value) generated by the magnetic coil XQ2 when it is turned off causes an impact on the power tube U5 and the power tube U6; the fifth energy storage circuit includes an energy storage resistor R47 and an energy storage capacitor C9, one end of the energy storage resistor R47 is connected to one end of the energy storage capacitor C9, the output end of the excitation coil drive circuit, one end of the excitation coil XQ5 and the other end of the energy storage resistor R47 are connected, and the other end of the energy storage capacitor C9 is connected to the battery ground terminal; the fifth freewheeling circuit includes an excitation unit freewheeling diode EJG5, the cathode of the excitation unit freewheeling diode EJG5, the output end of the excitation coil drive circuit and one end of the excitation coil XQ5 are connected, and the anode of the excitation unit freewheeling diode EJG5 is connected to the battery ground terminal; The sixth excitation coil control circuit includes an optocoupler G10, a current limiting resistor R40, a pull-down resistor R41, a pull-up resistor R42 and a freewheeling diode D10, the third pulse width modulation signal output terminal of the single-chip computer is connected to one end of the current limiting resistor R40, the other end of the current limiting resistor R40 and one end of the pull-down resistor R41 are connected to the first pin of the optocoupler G10, the second pin of the optocoupler G10 and the other end of the pull-down resistor R41 are connected to the ground terminal of the single-chip computer, the third pin of the optocoupler G10 and the positive electrode of the freewheeling diode D10 are connected to the ground terminal of the battery, the fourth pin of the optocoupler G10 and the negative electrode of the freewheeling diode D10 are connected to one end of the pull-up resistor R42, and the other end of the pull-up resistor R42 is connected to the positive input voltage of the battery; The sixth excitation coil driving circuit includes power tube U7 and power tube U8, the third pins of power tube U7 and power tube U8 are connected to the fourth pin of optocoupler G10, the fourth and tape automatic combination pins of power tube U7 and power tube U8 are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of power tube U7 and power tube U8 are connected to one end of excitation coil XQ6, and the other end of excitation coil XQ6 is connected to the ground terminal of the battery; the sixth overcurrent detection circuit includes detection resistor R48, detection resistor R49, detection resistor R50 and detection resistor R51, the third analog-to-digital conversion port of the single-chip microcomputer, one end of detection resistor R48 and one end of detection resistor R49 are connected, and the other end of detection resistor R48 is connected to power tube The fifth pin of U7, the other end of the detection resistor R49 is connected to the ground terminal of the single-chip computer, the fourth analog-to-digital conversion port of the single-chip computer, one end of the detection resistor R50 and one end of the detection resistor R51 are connected, the other end of the detection resistor R50 is connected to the fifth pin of the power tube U8, and the other end of the detection resistor R51 is connected to the ground terminal of the single-chip computer; in addition, it also includes a sixth energy storage circuit and a sixth freewheeling circuit. The sixth energy storage circuit stores a part of the electric energy when the excitation coil XQ6 is powered on, so that the voltage value at both ends of the excitation coil XQ6 will not increase suddenly, and releases a part of the electric energy when the excitation coil XQ6 is powered off, so that the voltage value at both ends of the excitation coil XQ6 will not decrease suddenly, thereby protecting the circuit; the sixth freewheeling circuit can prevent the excitation coil XQ6 from being powered on. The self-induced electromotive force (high voltage value) generated by the magnetic coil XQ6 when it is turned off causes an impact on the power tube U7 and the power tube U8; the sixth energy storage circuit includes an energy storage resistor R52 and an energy storage capacitor C10, one end of the energy storage resistor R52 is connected to one end of the energy storage capacitor C10, the output end of the excitation coil drive circuit, one end of the excitation coil XQ6 and the other end of the energy storage resistor R52 are connected, and the other end of the energy storage capacitor C10 is connected to the battery ground terminal; the sixth freewheeling circuit includes an excitation unit freewheeling diode EJG6, the cathode of the excitation unit freewheeling diode EJG6, the output end of the excitation coil drive circuit and one end of the excitation coil XQ6 are connected, and the anode of the excitation unit freewheeling diode EJG6 is connected to the battery ground terminal; Among them, the models of power tube U5, power tube U6, power tube U7 and power tube U8 are BTS50085.

[0030] Working principle: The fifth excitation coil control circuit controls the on and off of the power tube U5 and the power tube U6. I 5 = The fifth conduction current I 5-1 +Fifth conduction dichotomous current I 5-2 When the first pulse width modulation signal output terminal of the single chip is at a low level, the optocoupler G9 is not conducting, and the voltage of the fourth pin of the optocoupler G9 is U in-5 is high level, then the fifth excitation coil drive circuit, the fifth overcurrent detection circuit, the fifth energy storage circuit, and the fifth freewheeling circuit U in-5 When the first pulse width modulation signal output terminal of the single chip microcomputer is at a high level, the optical coupler G9 is turned on, and the voltage of the fourth pin of the optical coupler G9 is U in-5 is low level, then the fifth excitation coil drive circuit, the fifth overcurrent detection circuit, the fifth energy storage circuit, and the fifth freewheeling circuit U in-5 The power tube U5 and the power tube U6 are turned on. The fourth and automatic tape combination pins of the power tube U5 are connected to the first, second, sixth and seventh pins. The fourth and automatic tape combination pins of the power tube U6 are connected to the first, second, sixth and seventh pins. The coil XQ5 generates a magnetic field. When the coil XQ5 is turned on, if the fifth conduction current is I 5-1 The value is within the rated current value of the power tube U5. The fourth and tape automatic combination pins of the power tube U5 are connected to the first, second, sixth and seventh pins. The coil XQ5 is turned on. At this time, the fifth pin IS of the power tube U5 outputs a high level. The voltage value of the first analog-to-digital conversion port of the single-chip computer is a high level. When the coil XQ5 is turned on, if the fifth conduction current is divided into two I 5-2 The value is within the rated current value of the power tube U6. The fourth and tape automatic combination pins of the power tube U6 are connected to the first, second, sixth and seventh pins. The coil XQ5 is turned on. At this time, the fifth pin IS of the power tube U6 outputs a high level. The voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a high level. When the coil XQ5 is turned on, if the fifth conduction current is I 5-1The value exceeds the rated current value of the power tube U5, the fourth and tape automatic combination pins of the power tube U5 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U5 outputs a low level, and the voltage value of the first analog-to-digital conversion port of the single-chip computer is a low level; when the coil XQ5 is turned on, if the fifth conduction current is divided into two I 5-2 The value exceeds the rated current value of the power tube U6, and the fourth and tape automatic combination pins of the power tube U6 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U6 outputs a low level, and the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a low level. When the first pulse width modulation signal output end of the single-chip microcomputer is a high level, if the voltage value of the first analog-to-digital conversion port of the single-chip microcomputer is a low level, or the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a low level, at this time, the single-chip microcomputer MC9S12XS128MAA assigns the first pulse width modulation signal output end to 0, and the power tubes U5 and U6 are protected from circuit breaker.

[0031] The sixth excitation coil control circuit controls the on and off of the power tube U7 and the power tube U8. I 6 = The sixth conduction current I 6-1 +Sixth conduction dichotomous current I 6-2 When the third pulse width modulation signal output terminal of the single chip microcomputer is at a low level, the optocoupler G10 is not conducting, and the voltage of the fourth pin of the optocoupler G10 is U in-6 is high level, then the sixth excitation coil drive circuit, the sixth overcurrent detection circuit, the sixth energy storage circuit, and the sixth freewheeling circuit U in-6 When the third pulse width modulation signal output terminal of the single chip microcomputer is at a high level, the optical coupler G10 is turned on, and the voltage of the fourth pin of the optical coupler G10 is U in-6 is low level, then the sixth excitation coil drive circuit, the sixth overcurrent detection circuit, the sixth energy storage circuit, and the sixth freewheeling circuit U in-6 The power tube U7 and the power tube U8 are turned on, the fourth and the automatic tape combination pins of the power tube U7 are connected to the first, second, sixth and seventh pins, the fourth and the automatic tape combination pins of the power tube U8 are connected to the first, second, sixth and seventh pins, and the coil XQ6 generates a magnetic field. When the coil XQ6 is turned on, if the sixth conduction current I 6-1The value is within the rated current value of the power tube U7, the fourth and tape automatic combination pins of the power tube U7 are connected to the first, second, sixth and seventh pins, and the coil XQ6 is turned on. At this time, the fifth pin IS of the power tube U7 outputs a high level, and the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a high level; when the coil XQ6 is turned on, if the sixth conduction current is divided into two I 6-2 The value is within the rated current value of the power tube U8, the fourth and tape automatic combination pins of the power tube U8 are connected to the first, second, sixth and seventh pins, and the coil XQ6 is turned on. At this time, the fifth pin IS of the power tube U8 outputs a high level, and the voltage value of the fourth analog-to-digital conversion port of the single-chip microcomputer is a high level; when the coil XQ6 is turned on, if the sixth conduction current is I 6-1 The value exceeds the rated current value of the power tube U7, the fourth and tape automatic combination pins of the power tube U7 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U7 outputs a low level, and the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a low level; when the coil XQ6 is turned on, if the sixth conduction current is divided into two I 6-2 The value exceeds the rated current value of the power tube U8, and the fourth and tape automatic combination pins of the power tube U8 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U8 outputs a low level, and the voltage value of the fourth analog-to-digital conversion port of the single-chip microcomputer is a low level. When the third pulse width modulation signal output end of the single-chip microcomputer is a high level, if the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a low level, or the voltage value of the fourth analog-to-digital conversion port of the single-chip microcomputer is a low level, at this time, the single-chip microcomputer MC9S12XS128MAA assigns the third pulse width modulation signal output end to 0, and the power tubes U7 and U8 are protected from circuit breaker.

[0032] In order to further reduce the number of electromagnetic retarder excitation coils and reduce the difficulty of the excitation coil winding process, the following method can be used: Fig.15 and Fig.16 In the single excitation coil solution shown, the excitation coil control circuit, the excitation coil drive circuit and the excitation coil are all one group, and the overcurrent detection circuit is four groups, as follows: The seventh excitation coil control circuit includes an optocoupler G11, a current limiting resistor R53, a pull-down resistor R54, a pull-up resistor R55 and a freewheeling diode D11, a first pulse width modulation signal output terminal of the single-chip microcomputer is connected to one end of the current limiting resistor R53, the other end of the current limiting resistor R53 and one end of the pull-down resistor R54 are connected to a first pin of the optocoupler G11, a second pin of the optocoupler G11 and the other end of the pull-down resistor R54 are connected to a ground terminal of the single-chip microcomputer, a third pin of the optocoupler G11 and a positive electrode of the freewheeling diode D11 are connected to a ground terminal of a battery, a fourth pin of the optocoupler G11 and a negative electrode of the freewheeling diode D11 are connected to one end of the pull-up resistor R55, and the other end of the pull-up resistor R55 is connected to a positive input voltage of the battery; the seventh The excitation coil driving circuit includes power tube U9, power tube U10, power tube U11 and power tube U12, the third pins of power tube U9, power tube U10, power tube U11 and power tube U12 are all connected to the fourth pin of optocoupler G11, the fourth and tape automatic combination pins of power tube U9, power tube U10, power tube U11 and power tube U12 are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of power tube U9, power tube U10, power tube U11 and power tube U12 are connected to one end of excitation coil XQ7, and the other end of excitation coil XQ7 is connected to the ground terminal of the battery; the seventh overcurrent detection circuit includes detection resistors R56, R57, R58 and R60. 59, detection resistor R60, detection resistor R61, detection resistor R62 and detection resistor R63, the first analog-to-digital conversion port of the single-chip microcomputer, one end of the detection resistor R56 and one end of the detection resistor R57 are connected, the other end of the detection resistor R56 is connected to the fifth pin of the power tube U9, the other end of the detection resistor R57 is connected to the ground terminal of the single-chip microcomputer, the second analog-to-digital conversion port of the single-chip microcomputer, one end of the detection resistor R58 and one end of the detection resistor R59 are connected, the other end of the detection resistor R58 is connected to the fifth pin of the power tube U10, the other end of the detection resistor R59 is connected to the ground terminal of the single-chip microcomputer, the third analog-to-digital conversion port of the single-chip microcomputer, one end of the detection resistor R60 and one end of the detection resistor R61 are connected, the detection resistor The other end of R60 is connected to the fifth pin of the power tube U11, the other end of the detection resistor R61 is connected to the ground terminal of the single-chip computer, the fourth analog-to-digital conversion port of the single-chip computer, one end of the detection resistor R62 and one end of the detection resistor R63 are connected, the other end of the detection resistor R62 is connected to the fifth pin of the power tube U12, and the other end of the detection resistor R63 is connected to the ground terminal of the single-chip computer; in addition, it also includes a seventh energy storage circuit and a seventh freewheeling circuit. The seventh energy storage circuit stores a part of the electric energy when the excitation coil XQ7 is powered on, so that the voltage value at both ends of the excitation coil XQ7 will not increase suddenly, and releases a part of the electric energy when the excitation coil XQ7 is powered off, so that the voltage value at both ends of the excitation coil XQ7 will not decrease suddenly, thereby protecting the circuit;The seventh freewheeling circuit can prevent the self-induced electromotive force (high voltage value) generated by the excitation coil XQ7 when it is turned off from causing impact on the power tube U9, the power tube U10, the power tube U11 and the power tube U12; the seventh energy storage circuit includes an energy storage resistor R64 and an energy storage capacitor C11, one end of the energy storage resistor R64 is connected to one end of the energy storage capacitor C11, the output end of the excitation coil drive circuit, one end of the excitation coil XQ7 and the other end of the energy storage resistor R64 are connected, and the other end of the energy storage capacitor C11 is connected to the battery ground terminal; the seventh freewheeling circuit includes an excitation unit freewheeling diode EJG7, the negative pole of the excitation unit freewheeling diode EJG7, the output end of the excitation coil drive circuit and one end of the excitation coil XQ7 are connected, and the positive pole of the excitation unit freewheeling diode EJG7 is connected to the battery ground terminal; Among them, the models of power tube U9, power tube U10, power tube U11 and power tube U12 are BTS50085.

[0033] Working principle: The seventh excitation coil control circuit controls the on and off of the power tubes U9, U10, U11 and U12. I 7 = The seventh conduction current I 7-1 +Seventh conduction dichotomous current I 7-2 + Seventh conduction three-point current I 7-3 +Seventh conduction quarter current I 7-4 When the first pulse width modulation signal output terminal of the single chip microcomputer is at a low level, the optocoupler G11 is not conducting, and the voltage of the fourth pin of the optocoupler G11 is U in-7 is high level, then the seventh excitation coil drive circuit, the seventh overcurrent detection circuit, the seventh energy storage circuit, and the seventh freewheeling circuit U in-7 When the first pulse width modulation signal output terminal of the single-chip microcomputer is at a high level, the power tube U9, the power tube U10, the power tube U11, and the power tube U12 are all off, the fourth and automatic tape combination pins of the power tube U9 are disconnected from the first, second, sixth, and seventh pins, the fourth and automatic tape combination pins of the power tube U10 are disconnected from the first, second, sixth, and seventh pins, the fourth and automatic tape combination pins of the power tube U11 are disconnected from the first, second, sixth, and seventh pins, the fourth and automatic tape combination pins of the power tube U12 are disconnected from the first, second, sixth, and seventh pins, and the coil XQ7 does not generate a magnetic field; when the first pulse width modulation signal output terminal of the single-chip microcomputer is at a high level, the optical coupler G11 is turned on, and the voltage of the fourth pin of the optical coupler G11 is U in-7 is low level, then the seventh excitation coil drive circuit, the seventh overcurrent detection circuit, the seventh energy storage circuit, and the seventh freewheeling circuitU in-7 The power tube U9, power tube U10, power tube U11, and power tube U12 are all turned on. The fourth and automatic tape combination pins of power tube U9 are connected to the first, second, sixth, and seventh pins. The fourth and automatic tape combination pins of power tube U10 are connected to the first, second, sixth, and seventh pins. The fourth and automatic tape combination pins of power tube U11 are connected to the first, second, sixth, and seventh pins. The fourth and automatic tape combination pins of power tube U12 are connected to the first, second, sixth, and seventh pins. Coil XQ7 generates a magnetic field. When coil XQ7 is turned on, if the seventh conduction current is one-point I 7-1 The value is within the rated current value of the power tube U9, the fourth and tape automatic combination pins of the power tube U9 are connected to the first, second, sixth and seventh pins, and the coil XQ7 is turned on. At this time, the seventh pin IS of the power tube U9 outputs a high level, and the voltage value of the first analog-to-digital conversion port of the single-chip computer is a high level; when the coil XQ7 is turned on, if the seventh conduction current is divided into two I 7-2 The value is within the rated current value of the power tube U10, the fourth and tape automatic combination pins of the power tube U10 are connected to the first, second, sixth and seventh pins, and the coil XQ7 is turned on. At this time, the fifth pin IS of the power tube U10 outputs a high level, and the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a high level; when the coil XQ7 is turned on, if the seventh conduction current is three-point I 7-3 The value is within the rated current value of the power tube U11, the fourth and tape automatic combination pins of the power tube U11 are connected to the first, second, sixth and seventh pins, and the coil XQ7 is turned on. At this time, the fifth pin IS of the power tube U11 outputs a high level, and the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a high level; when the coil XQ7 is turned on, if the seventh conduction current is divided into four I 7-4 The value is within the rated current value of the power tube U12. The fourth and tape automatic combination pins of the power tube U12 are connected to the first, second, sixth and seventh pins. The coil XQ7 is turned on. At this time, the fifth pin IS of the power tube U12 outputs a high level, and the voltage value of the fourth analog-to-digital conversion port of the single-chip microcomputer is a high level. When the coil XQ7 is turned on, if the seventh conduction current is I 7-1 The value exceeds the rated current value of the power tube U9, the fourth and tape automatic combination pins of the power tube U9 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U9 outputs a low level, and the voltage value of the first analog-to-digital conversion port of the single-chip computer is a low level; when the coil XQ7 is turned on, if the seventh conduction current is divided into two I 7-2The value exceeds the rated current value of the power tube U10, and the fourth and tape automatic combination pins of the power tube U10 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U10 outputs a low level, and the voltage value of the second analog-to-digital conversion port of the single-chip microcomputer is a low level; when the coil XQ7 is turned on, if the seventh conduction current is three-point I 7-3 The value exceeds the rated current value of the power tube U11, and the fourth and tape automatic combination pins of the power tube U11 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U11 outputs a low level, and the voltage value of the third analog-to-digital conversion port of the single-chip microcomputer is a low level; when the coil XQ7 is turned on, if the seventh conduction current is divided into four I 7-4 The value exceeds the rated current value of the power tube U12, and the fourth and tape automatic combination pins of the power tube U12 are disconnected from the first, second, sixth and seventh pins. At this time, the fifth pin IS of the power tube U12 outputs a low level, and the voltage value of the fourth analog-to-digital conversion port of the single-chip computer is a low level. When the first pulse width modulation signal output end of the single-chip computer is a high level, if the voltage value of the first analog-to-digital conversion port of the single-chip computer is a low level, or the voltage value of the second analog-to-digital conversion port of the single-chip computer is a low level, or the voltage value of the third analog-to-digital conversion port of the single-chip computer is a low level, or the voltage value of the fourth analog-to-digital conversion port of the single-chip computer is a low level, then the single-chip computer MC9S12XS128MAA assigns the first pulse width modulation signal output end to 0, and the power tubes U9, U10, U11 and U12 are protected from circuit breaker.

[0034] Example 2

[0035] This embodiment provides an electromagnetic retarder, which is configured with the electromagnetic retarder control system described in Embodiment 1.

[0036] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An electromagnetic retarder control system, characterized in that: It includes a single-chip microcomputer, an excitation coil control circuit, an excitation coil drive circuit and an overcurrent detection circuit. The pulse width modulation signal output end of the single-chip microcomputer is connected to the excitation coil control circuit, the analog-to-digital conversion port of the single-chip microcomputer is connected to the overcurrent detection circuit, the excitation coil drive circuit is connected to the excitation coil and is used to drive multiple or single excitation coils. The excitation coil control circuit and the overcurrent detection circuit are both connected to the excitation coil drive circuit and are used to reduce the current of the driven excitation coil to 0A when the current exceeds the limit.

2. The electromagnetic retarder control system according to claim 1, characterized in that: It also includes an energy storage circuit, which includes an energy storage resistor and an energy storage capacitor. One end of the energy storage resistor is connected to one end of the energy storage capacitor, the output end of the excitation coil drive circuit, one end of the excitation coil and the other end of the energy storage resistor are connected, and the other end of the energy storage capacitor is connected to the ground terminal of the battery.

3. The electromagnetic retarder control system according to claim 1, characterized in that: It also includes a freewheeling circuit, which includes an excitation unit freewheeling diode, the cathode of the excitation unit freewheeling diode, the output end of the excitation coil drive circuit and one end of the excitation coil are connected, and the anode of the excitation unit freewheeling diode is connected to the ground terminal of the battery.

4. The electromagnetic retarder control system according to claim 1, characterized in that: The excitation coil control circuit, the excitation coil drive circuit, the overcurrent detection circuit and the excitation coil are all four groups; Each group of excitation coil control circuits includes an optocoupler, a current limiting resistor, a pull-down resistor, a pull-up resistor and a freewheeling diode, the pulse width modulation signal output end of the single-chip microcomputer is connected to one end of the current limiting resistor, the other end of the current limiting resistor and one end of the pull-down resistor are connected to the first pin of the optocoupler, the second pin of the optocoupler and the other end of the pull-down resistor are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler and the positive electrode of the freewheeling diode are connected to the ground terminal of the battery, the fourth pin of the optocoupler and the negative electrode of the freewheeling diode are connected to one end of the pull-up resistor, and the other end of the pull-up resistor is connected to the positive input voltage of the battery; Each set of excitation coil driving circuits includes a power tube, the third pin of the power tube is connected to the fourth pin of the optocoupler, the fourth and tape automatic combination pins of the power tube are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the power tube are connected to one end of the excitation coil, and the other end of the excitation coil is connected to the ground terminal of the battery; Each overcurrent detection circuit includes a first detection resistor and a second detection resistor. The analog-to-digital conversion port of the microcontroller, one end of the first detection resistor and one end of the second detection resistor are connected, the other end of the first detection resistor is connected to the fifth pin of the power tube, and the other end of the second detection resistor is connected to the ground terminal of the microcontroller.

5. The electromagnetic retarder control system according to claim 1, characterized in that: There are two groups of excitation coil control circuit, excitation coil drive circuit and excitation coil, and four groups of overcurrent detection circuit; Each group of excitation coil control circuits includes an optocoupler, a current limiting resistor, a pull-down resistor, a pull-up resistor and a freewheeling diode, the pulse width modulation signal output end of the single-chip microcomputer is connected to one end of the current limiting resistor, the other end of the current limiting resistor and one end of the pull-down resistor are connected to the first pin of the optocoupler, the second pin of the optocoupler and the other end of the pull-down resistor are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler and the positive electrode of the freewheeling diode are connected to the ground terminal of the battery, the fourth pin of the optocoupler and the negative electrode of the freewheeling diode are connected to one end of the pull-up resistor, and the other end of the pull-up resistor is connected to the positive input voltage of the battery; Each set of excitation coil driving circuits includes two power tubes, the third pins of the two power tubes are connected to the fourth pin of the optocoupler, the fourth and tape automatic combination pins of the two power tubes are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the two power tubes are connected to one end of the excitation coil, and the other end of the excitation coil is connected to the ground terminal of the battery; Each overcurrent detection circuit includes a first detection resistor and a second detection resistor. The analog-to-digital conversion port of the microcontroller, one end of the first detection resistor and one end of the second detection resistor are connected, the other end of the first detection resistor is connected to the fifth pin of the power tube, and the other end of the second detection resistor is connected to the ground terminal of the microcontroller.

6. The electromagnetic retarder control system according to claim 1, characterized in that: The excitation coil control circuit, the excitation coil drive circuit and the excitation coil are all one group, and the overcurrent detection circuit is four groups; The excitation coil control circuit includes an optocoupler, a current limiting resistor, a pull-down resistor, a pull-up resistor and a freewheeling diode, the pulse width modulation signal output end of the single-chip microcomputer is connected to one end of the current limiting resistor, the other end of the current limiting resistor and one end of the pull-down resistor are connected to the first pin of the optocoupler, the second pin of the optocoupler and the other end of the pull-down resistor are connected to the ground terminal of the single-chip microcomputer, the third pin of the optocoupler and the positive electrode of the freewheeling diode are connected to the ground terminal of the battery, the fourth pin of the optocoupler and the negative electrode of the freewheeling diode are connected to one end of the pull-up resistor, and the other end of the pull-up resistor is connected to the positive input voltage of the battery; The excitation coil driving circuit includes four power tubes, the third pins of the four power tubes are connected to the fourth pin of the optocoupler, the fourth and tape automatic combination pins of the four power tubes are connected to the positive input voltage of the battery, the first, second, sixth and seventh pins of the four power tubes are connected to one end of the excitation coil, and the other end of the excitation coil is connected to the ground terminal of the battery; Each overcurrent detection circuit includes a first detection resistor and a second detection resistor. The analog-to-digital conversion port of the microcontroller, one end of the first detection resistor and one end of the second detection resistor are connected, the other end of the first detection resistor is connected to the fifth pin of the power tube, and the other end of the second detection resistor is connected to the ground terminal of the microcontroller.

7. The electromagnetic retarder control system according to claim 1, characterized in that: It also includes a conversion circuit, which includes a switching regulator, a first inductor, a second inductor, a first polarity capacitor, a second polarity capacitor, a first capacitor and a second capacitor. The first pin of the switching regulator, the positive electrode of the first polarity capacitor, and one end of the first capacitor are connected to the positive input voltage of the battery, the fifth pin of the switching regulator, the third pin of the switching regulator, the negative electrode of the first polarity capacitor, and the other end of the first capacitor are connected to the ground terminal of the battery, the fourth pin of the switching regulator, one end of the first inductor, the positive electrode of the second polarity capacitor, and one end of the second capacitor are connected to the positive voltage of the single-chip computer, the negative electrode of the second polarity capacitor and the other end of the second capacitor are connected to the ground terminal of the single-chip computer, and the two ends of the second inductor are respectively connected to the ground terminal of the battery and the ground terminal of the single-chip computer.

8. An electromagnetic retarder, characterized in that: The electromagnetic retarder is configured with the electromagnetic retarder control system according to any one of claims 1 to 7.

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