Method for controlling power supply of excitation coil of excitation generator, control circuit and device
By monitoring the status of the engine and exciter generator in real time, the exciter power supply circuit is controlled to supply power to the exciter coil after the engine starts and to cut off the power supply after the exciter motor is powered on. This solves the problems of battery depletion and instrument overheating caused by the exciter coil supplying power when the vehicle is not running, and improves the reliability of the exciter generator and vehicle safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHENGZHOU SENPENG ELECTRONICS TECH
- Filing Date
- 2022-12-30
- Publication Date
- 2026-05-15
AI Technical Summary
When the vehicle is not started, the excitation generator continues to supply power to the excitation coil, causing the battery to deplete and the instrument current-limiting resistor to overheat, affecting vehicle operation and safety.
By real-time monitoring of the engine start-up status and the rotation of the excitation generator, the excitation power supply circuit is controlled to supply power to the excitation coil after the engine starts, and to cut off the power supply circuit after the excitation motor is self-powered. Combined with the current-limiting resistor and the anti-current-backflow circuit, overheating and battery depletion are avoided.
This effectively prevents battery depletion and instrument overheating caused by the excitation coil supplying power when the generator is not running, thus improving the reliability of the excitation generator and the safety of the vehicle.
Smart Images
Figure CN116015126B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of automotive control technology, and in particular to a power supply control method, control circuit, and excitation generator device for an excitation generator in a motor vehicle. Background Technology
[0002] With the development of in-vehicle electronics technology, more and more vehicles are equipped with intelligent terminal devices, which require 24-hour uninterrupted power supply. Examples include "intelligent electric loading and unloading platforms" in many commercial vans, "intelligent electric garbage weighing" and "intelligent electric garbage bin loading and unloading" in garbage trucks, "intelligent tarpaulin devices" in construction waste transport vehicles, and "terminal video equipment" in commercial buses. This necessitates matching the vehicles with "large-capacity batteries," which in turn requires the installation of multiple excitation generators to solve the vehicle battery charging problem. Therefore, to save costs, commercial vehicles need multiple excitation generators for excitation output.
[0003] The operating conditions of an automotive exciter generator are as follows: After the engine starts, before the generator starts working, an external excitation current of approximately 100mA is required to supply the generator's excitation coil. After the generator starts generating electricity normally, it provides its own excitation current. However, in actual use, the following situations exist: 1. If the excitation current is too small, it will lead to insufficient magnetic flux in the generator. When the engine is at low speed, the change in magnetic flux per unit time is too small, resulting in insufficient generator output power. To ensure the generator output power meets the requirements, the engine speed must be increased. The vehicle's idle speed is only 1000 rpm (gasoline) or 500 to 800 rpm (diesel). The engine speed for economical operation is 1500 to 3500 rpm (gasoline) or 1000 to 3000 rpm (diesel). Exceeding and operating at high speeds for extended periods poses a risk of engine damage. 2. While a large excitation current can solve the problem of insufficient power generation at low speeds and during vehicle operation, after prolonged engine operation, the overall engine temperature reaches around 90 degrees Celsius. An excessively large excitation current poses a risk of overheating and burning out the excitation coil, ultimately preventing the vehicle's generator from generating electricity normally. 3. During vehicle use, the vehicle's battery voltage fluctuates within a range (11V to 13.5V), resulting in an unstable excitation current supplied to the excitation motor. 4. A significant issue is that when the vehicle doors are open or the instrument cluster wake-up trigger is activated, but the engine is not running, the driver may be resting in the car for an extended period, forget to lock the doors, or there may be a malfunction in the vehicle wake-up function. In such cases, the vehicle cannot enter low-power mode, and the excitation current will continue to be supplied. A single generator consumes 0.1A * 24h = 2.4Ah of electricity per day. While most vehicles have a 40Ah or 60Ah battery, over time this may decrease to around 10Ah. Prolonged supply of excitation current to the generator can lead to battery depletion, affecting battery life and vehicle starting. This phenomenon is even more pronounced in commercial vehicles equipped with two or more excitation generators. 5. The function of the vehicle's instrument cluster is to provide real-time feedback to the driver on the vehicle's operating status, including the power supply from the instrument cluster to the vehicle's excitation generator, thus ensuring proper battery charging after the engine starts. The instrument cluster needs to output approximately 100mA of excitation current, requiring a current-limiting resistor to prevent overcurrent from burning out the excitation coil of the excitation generator. For a 12V system, the resistor value is approximately 120Ω, with a power requirement of 1.2W (for a 24V system, the resistor value is approximately 240Ω, with a power requirement of 2.4W).Passenger vehicles typically have one excitation generator, with the instrument panel internally providing the excitation power supply circuit for the generator. The current-limiting resistor in this circuit requires a power rating of 1.2W or 2.4W. Commercial vehicles, however, typically have two or more excitation generators, with the instrument panel internally providing the excitation power supply circuit for the generator. The current-limiting resistor in this circuit requires a power rating of 1.2W*2 or 2.4W*2 or higher. This causes the internal resistors of the instrument panel to overheat, severely impacting the instrument panel's lifespan and posing a serious safety hazard to the vehicle. Therefore, the instrument panel needs to perform real-time control of the excitation power supply to the generator based on the vehicle's operating status. Summary of the Invention
[0004] The purpose of this invention is to provide a method for controlling the power supply to the excitation coil of a motor vehicle exciter, to prevent battery depletion caused by supplying power to the excitation coil when the vehicle is not running. Simultaneously, this invention also provides an excitation power supply control circuit for an exciter to solve the problem of battery depletion caused by supplying power to the excitation coil when the vehicle is not running. This invention also provides an exciter generator device to solve the problem of battery depletion caused by supplying power to the excitation coil when the vehicle is not running.
[0005] To achieve the above objectives, the present invention provides a method for controlling the power supply of the excitation coil of a motor vehicle excitation generator, the method comprising the following steps:
[0006] S1: After the system is powered on, it will detect in real time whether the engine starts or the excitation generator starts to rotate;
[0007] S2: When the engine starts normally or the excitation generator starts rotating normally, the excitation power supply circuit is controlled to output a set current to the excitation coil.
[0008] S3: After the engine starts, the feedback voltage of the excitation coil is detected in real time. When the feedback voltage is not less than the set voltage, the power supply current is cut off and the excitation motor enters the self-powered stage of the excitation coil.
[0009] This invention provides a novel excitation coil power supply control method. In this method, power is supplied to the excitation coil only after the engine starts. At this time, the excitation motor starts working and can immediately establish a generating voltage for self-powering. The back EMF can also suppress the current in the power supply circuit, reducing and avoiding the heating and burnout of the current-limiting resistor in the power supply circuit. This avoids the loss of battery power due to the power supply circuit supplying power when the engine is not running, and also avoids the overheating or even burnout of the excitation coil caused by the back EMF current not being established when the excitation generator rotor is not rotating and the excitation coil is not running when the engine is not running.
[0010] Furthermore, during normal operation of the engine and exciter generator, the feedback voltage of the excitation coil is monitored in real time. If the feedback voltage is lower than the set supply voltage, the excitation power supply circuit is controlled to simultaneously supply power to the excitation coil until the feedback voltage is not less than the set voltage. This improvement can, for example, provide excitation current in a timely manner to stabilize power generation when insufficient self-powered excitation current at engine idling leads to insufficient power generation.
[0011] Furthermore, during normal operation of the engine and exciter generator, the feedback voltage of the exciter coil is monitored in real time. If the feedback voltage is equal to or close to zero, the exciter power supply circuit is controlled to supply power to the exciter coil. If the feedback voltage still does not increase, it is determined that the exciter motor is faulty, and a fault signal is issued. This improvement not only stabilizes the power generation but also enables timely detection of exciter motor fault conditions.
[0012] Corresponding to the above method, the present invention also provides an excitation power supply control circuit for an excitation generator. This circuit mainly consists of an electronic switch circuit and a current-limiting resistor circuit connected in series. The input and output terminals of the electronic switch circuit are respectively connected to the positive terminal of the battery power supply and the input terminal of the excitation coil of the excitation generator. The control signal of the electronic switch circuit is connected to the power switch control port of the microprocessor. The microprocessor is provided with an engine or excitation generator rotation detection signal input port for detecting whether the engine or excitation generator is rotating normally. A voltage feedback detection circuit is connected to the input terminal of the excitation coil of the excitation generator. The output signal of the voltage feedback detection circuit is connected to the excitation feedback voltage detection port of the microprocessor. When the system is powered on, the microprocessor detects in real time whether the engine has started or whether the excitation generator has started rotating. When it is detected that the engine has started normally or the excitation generator has started rotating normally, the microprocessor controls the excitation power supply circuit to output a set current to the excitation coil. After the engine starts, the microprocessor detects the feedback voltage of the excitation coil in real time. When the feedback voltage is not less than the set voltage, the microprocessor turns off the electronic switch to cut off the power supply current, and the excitation motor enters the excitation coil self-power supply stage.
[0013] This invention provides a novel excitation coil power supply control circuit. In this circuit, power is supplied to the excitation coil only after the engine starts. At this time, the excitation motor starts working and can immediately establish a generating voltage for self-powering. The back EMF can also suppress the current in the power supply circuit, reducing and avoiding the heating and burnout of the current-limiting resistor in the power supply circuit. This also avoids the loss of battery power due to the power supply circuit supplying power when the engine is not running, and also avoids the overheating or even burnout of the excitation coil caused by the excitation generator rotor not rotating and the excitation coil not establishing a back EMF current when the current flows directly.
[0014] Furthermore, a backflow prevention circuit unit is connected in series between the output terminal of the control circuit and the input terminal of the excitation coil. This is to prevent the excitation current from being supplied to the instrument's excitation circuit and damaging the instrument when the engine is running normally and the excitation current of the excitation generator is "provided by the generator itself".
[0015] Furthermore, the electronic switch circuit is composed of a switching transistor circuit and a power electronic switch control electrode connected together, and the two on / off terminals of the power electronic switch are connected in series with a current-limiting resistor circuit.
[0016] Furthermore, the current-limiting resistor circuit is used to limit the excitation current supply within a set range by coordinating the battery voltage value with the current-limiting resistor. This prevents overcurrent from burning out the excitation coil of the excitation generator.
[0017] Furthermore, the feedback voltage circuit is composed of a voltage divider circuit consisting of series resistors, and the voltage tapping point is set to be connected to the corresponding port of the microprocessor.
[0018] Meanwhile, this invention also provides an excitation generator device. The excitation coil of the excitation generator is connected to an excitation power supply control circuit. The excitation power supply control circuit is composed of an electronic switch circuit and a current-limiting resistor circuit connected in series. The input and output terminals of the electronic switch circuit are respectively connected to the positive terminal of the battery power supply and the input terminal of the excitation coil of the excitation generator. The control signal of the electronic switch circuit is connected to the power switch control port of the microprocessor. The microprocessor has an engine or excitation generator rotation detection signal input port for detecting whether the engine or excitation generator is rotating normally. A voltage feedback detection circuit is connected to the input terminal of the coil. The output signal of the voltage feedback detection circuit is connected to the excitation feedback voltage detection port of the microprocessor. When the system is powered on, the microprocessor detects in real time whether the engine has started or whether the excitation generator has started rotating. When the engine starts normally or the excitation generator starts rotating normally, the microprocessor controls the excitation power supply circuit to output a set current to the excitation coil. After the engine starts, the microprocessor detects the feedback voltage of the excitation coil in real time. When the feedback voltage is not less than the set voltage, the microprocessor turns off the electronic switch to cut off the power supply current, and the excitation motor enters the excitation coil self-powered stage.
[0019] This invention provides a novel excitation generator device. When the vehicle is not running, the excitation current supply to the generator is cut off. When the vehicle is running normally, the instrument panel continues to supply excitation current to the generator. This solves the problem of the instrument panel continuously supplying excitation power to the generator during shutdown, which can lead to overheating and damage to the instrument panel and prolonged battery discharge to the excitation coil, causing battery depletion and affecting vehicle operating life.
[0020] Furthermore, a backflow prevention circuit unit is connected in series between the output terminal of the control circuit and the input terminal of the excitation coil. This is to prevent the excitation current from being supplied to the instrument's excitation circuit and damaging the instrument when the engine is running normally and the excitation current of the excitation generator is "provided by the generator itself".
[0021] Furthermore, the electronic switch circuit is composed of a switching transistor circuit and a power electronic switch control electrode connected together, and the two on / off terminals of the power electronic switch are connected in series with a current-limiting resistor circuit.
[0022] Furthermore, the current-limiting resistor circuit is used to limit the excitation current supply within a set range by coordinating the battery voltage value with the current-limiting resistor. This prevents overcurrent from burning out the excitation coil of the excitation generator.
[0023] Furthermore, the feedback voltage circuit is composed of a voltage divider circuit consisting of series resistors, and the voltage tapping point is set to be connected to the corresponding port of the microprocessor. Attached Figure Description
[0024] Figure 1 This is a circuit diagram of the motor vehicle excitation generator device of the present invention. Detailed Implementation
[0025] The features and performance of the present invention will be further described in detail below with reference to embodiments.
[0026] like Figure 1 As shown, an embodiment of the motor vehicle excitation generator device of the present invention is as follows: In the excitation generator device, the excitation coil of the excitation generator is connected to the excitation power supply control circuit. The excitation power supply control circuit of the excitation generator is composed of an electronic switch circuit and a current-limiting resistor circuit connected in series. The input and output terminals of the electronic switch circuit are respectively connected to the positive terminal of the battery power supply and the input terminal of the excitation coil of the excitation generator. The electronic switch circuit is composed of a switching transistor Q1 and peripheral circuits connected to the control terminal of a power electronic switch Q2. The microprocessor MCU controls whether the power supply BAT should be turned on through Q1 and Q2. The two on / off terminals of the power electronic switch Q2 are connected in series with the current-limiting resistor circuit. The current-limiting resistor circuit is composed of a series branch of resistors R3 and R1 and a series branch of resistors R4 and R2 connected in parallel. In this embodiment, when the power supply voltage is constant, the resistance value of the current-limiting resistor circuit ensures that the current supplied to the excitation coil of the excitation motor is limited to an appropriate range to prevent excessive heat generation of the resistor and overheating and burnout of the excitation coil. In this embodiment, the resistance is 100mA (at 24V). The resistance value is halved when the power supply is 12V.
[0027] After the system is powered on, the microprocessor (MCU) monitors in real time whether the engine has started or the excitation generator has started rotating. When the engine starts normally or the excitation generator starts rotating normally, the MCU controls the excitation power supply circuit to output a set current to the excitation coil. The MCU also monitors the feedback voltage ADC-IN of the excitation coil in real time. When the feedback voltage is not less than the set voltage (in this embodiment, the set voltage is the voltage Bat of the power supply battery), the MCU turns off the electronic switch to cut off the power supply current, and the excitation motor enters the self-powered stage of the excitation coil.
[0028] The control signal of the electronic switch circuit is connected to the power switch control port I / O of the microprocessor MCU. The microprocessor MCU has an engine (or exciter generator) rotation detection pulse signal input port to detect whether the engine (or exciter generator) is rotating normally. Microprocessor MCU pulse detection: By detecting the engine pulse signal, it determines whether the engine is running or stopped, and decides whether to turn on the excitation power. When the instrument panel is in sleep mode, operating, and the engine is not running, the microprocessor MCU does not detect the pulse output from the engine pulse sensor. At this time, the microprocessor MCU's I / O control port outputs a "low level," Q1 is turned off, Q2 is turned off, and the excitation coil of the exciter generator loses current, reducing the power output of the vehicle's "battery." When the car engine starts, the starter motor requires a large starting current (the larger the engine emissions, the larger the starting current). At this time, the microprocessor MCU's I / O control port outputs a "low level," Q1 is turned off, ensuring the engine starts smoothly. After the vehicle engine starts successfully, the microprocessor MCU's I / O control port outputs a "high level," Q1 is turned on, and excitation current is normally supplied to the exciter generator's excitation coil.
[0029] A voltage feedback detection circuit is connected to the input terminal of the excitation coil of the exciter generator. The output signal of the voltage feedback detection circuit and the microprocessor MCU feedback voltage circuit are composed of a voltage divider circuit consisting of series resistors R5 and R6 and capacitors C2 and C1. The voltage sampling point is set as the series connection point of resistors R5 and R6. The ADC-IN is connected to the corresponding port of the microprocessor, the excitation feedback voltage detection port of the MCU—the ADC sampling port—to provide feedback on the status and normality of the excitation current. After the exciter generator generates electricity normally, the ADC analog acquisition circuit of the microprocessor MCU acquires the amplitude value of ADC_IN. (If the excitation current is provided by the generator itself after the exciter generator generates electricity normally, the voltage of the excitation coil is higher than the voltage of the battery BAT at this time.) If the amplitude of ADC_IN is higher than the set supply voltage Bat, and the MCU acquires the engine pulse signal, it indicates that the exciter generator is working normally. At this time, the MCU turns off the Q1 transistor and stops providing the excitation supply current.
[0030] When the engine stops running, the excitation voltage feedback circuit of the microprocessor MCU, i.e. the ADC analog acquisition circuit, acquires the amplitude value of ADC_IN. At this time, the acquired value of "ADC_IN" is close to "0V", and the pulse acquisition circuit of the MCU does not acquire the pulse signal of the engine. The I / O output control port of the MCU outputs "low level" to turn off "Q1" and achieve low power consumption.
[0031] A reverse current protection circuit unit is connected in series between the output terminal of the control circuit and the input terminal of the excitation coil. In this embodiment, it is composed of diode D1. Diode D1 prevents reverse current. When the engine is running normally, the excitation current of the excitation generator is provided by the generator itself, preventing current from being supplied to the excitation circuit of the instrument and damaging the instrument.
[0032] During normal engine operation, the exciter generator status is monitored: if the microprocessor (MCU) detects that the engine's pulse signal is normal, and the MCU's ADC acquires the "ADC_IN" signal as "0V" or close to "0V", the MCU can output a "1Hz PWM" signal through the "I / O output port" to control the "off / on" state of Q1, providing excitation current to the excitation coil of the exciter generator to ensure the normal operation of the exciter generator.
[0033] The MCU can output a 1Hz PWM signal through the I / O output port to control Q1 to "turn off / on". The MCU can also collect the voltage of "ADC_IN" through the ADC acquisition port. If the voltage is always close to "0V", the MCU can determine that "the excitation generator has failed" and the instrument will provide a fault indication.
[0034] An embodiment of the motor vehicle excitation generator excitation coil power supply control method of the present invention is as follows. The control method includes the following steps: S1: After the system is powered on, the microprocessor MCU detects the speed pulse signal emitted by the engine speed sensor in real time to determine whether the engine has started; S2: When the engine is detected to have started normally, the I / O port of the microprocessor MCU controls the transistor Q1 and the power electronic switch Q2 to turn on, and the excitation power supply circuit outputs a set current to the excitation coil; S3: After the engine starts, the feedback voltage circuit (analog sampling circuit---composed of a voltage divider circuit composed of series resistors R5, R6 and capacitors C2, C1) detects the feedback voltage ADC-IN of the excitation coil in real time. When the feedback voltage value ADC-IN is not less than the set voltage—the voltage Bat of the car battery—the power supply current is turned off, and the excitation motor enters the excitation coil self-power supply stage.
[0035] Since power is supplied to the excitation coil only after the engine starts, the excitation motor starts working at this time and can immediately establish a generating voltage for self-powering. The back EMF can also suppress the current in the power supply circuit, reduce and avoid the heating and burnout of the current-limiting resistor in the power supply circuit, avoid the loss of battery power due to the power supply circuit supplying power when the engine is not running, and also avoid the overheating or even burnout of the excitation coil caused by the excitation generator rotor not rotating and the excitation coil not establishing a back EMF current when the current flows directly.
[0036] During normal operation of the engine and exciter generator M, the feedback voltage of the exciter coil is monitored in real time. If the feedback voltage is lower than the set supply voltage, excitation current is supplied to the exciter coil of the exciter generator to ensure normal operation of the exciter motor. In other words, the microprocessor (MCU) detects that the engine's pulse signal is normal. If the MCU's ADC acquires an "ADC_IN" signal of "0V" or close to "0V", the MCU can output a "1Hz PWM" signal through the "I / O output port" to control the "off / on" state of Q1, controlling the exciter power supply circuit to simultaneously supply power to the exciter coil until the feedback voltage is not less than the set voltage. This is achieved by real-time monitoring of the exciter coil's feedback voltage ADC_IN. When the feedback voltage ADC_IN is not less than the set voltage—the voltage of the car battery (Bat)—the supply current is cut off, and the exciter motor enters the exciter coil self-powered stage. This method can, for example, address situations where insufficient exciter current during engine idling leads to insufficient power generation, allowing the exciter power supply circuit to assist in providing exciter current and stabilizing power generation.
[0037] There are two ways to determine whether the excitation generator is faulty: During the normal operation of the engine and the excitation generator, the feedback voltage of the excitation coil is detected in real time using the same method as described above. If the feedback voltage is equal to zero or close to zero, the excitation power supply circuit is then controlled to supply power to the excitation coil. If the feedback voltage still does not increase, it is determined that the excitation motor is faulty and a fault signal is issued.
[0038] An embodiment of the excitation power supply control circuit for the excitation generator of the present invention has been described in the embodiment of the motor vehicle excitation generator device, and will not be repeated here.
[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.
Claims
1. A method for controlling the power supply to the excitation coil of a motor vehicle excitation generator, characterized in that, This method is applied to an excitation power supply control circuit, which includes an electronic switch circuit, a current-limiting resistor circuit, a microprocessor, and a voltage feedback detection circuit. The electronic switch circuit and the current-limiting resistor circuit are connected in series. The input terminal of the electronic switch circuit is used to connect to the positive terminal of the battery power supply. The end of the current-limiting resistor circuit not connected to the electronic switch circuit is connected to the input terminal of the excitation coil of the excitation generator. The control terminal of the electronic switch circuit is connected to the power switch control port of the microprocessor. The microprocessor has an engine or excitation generator rotation detection signal input port for detecting whether the engine or excitation generator is rotating normally. The input terminal of the voltage feedback detection circuit is connected to the connection line between the current-limiting resistor and the input terminal of the excitation coil of the excitation generator. The output terminal of the voltage feedback detection circuit is connected to the excitation feedback voltage detection port of the microprocessor. The control method includes the following steps: S1: When the system is powered on, the microprocessor detects in real time whether the engine has started or the excitation generator has started to rotate. S2: When the engine starts normally or the excitation generator starts rotating normally, the microprocessor controls the electronic switch in the electronic switch circuit to turn on, thereby outputting a set current to the excitation coil. S3: After the engine starts, the microprocessor detects the feedback voltage of the excitation coil in real time through the voltage feedback detection circuit. When the feedback voltage is not less than the set voltage, the microprocessor turns off the electronic switch to cut off the power supply current, and the excitation generator enters the self-powered stage of the excitation coil. When the engine is running normally, when the feedback voltage is detected to be zero or close to zero, the microprocessor outputs a 1Hz PWM signal through the power switch control port to control the electronic switch and provide excitation current to the excitation coil of the excitation generator.
2. The method for controlling the power supply of the excitation coil of a motor vehicle excitation generator according to claim 1, characterized in that, During normal operation of the engine and exciter generator, the feedback voltage of the exciter coil is monitored in real time. If the feedback voltage is lower than the set supply voltage, the exciter power supply circuit is controlled to supply power to the exciter coil simultaneously until the feedback voltage is not less than the set voltage.
3. The method for power supply control of the excitation coil of a motor vehicle excitation generator according to claim 1, characterized in that, During normal operation of the engine and exciter generator, the feedback voltage of the exciter coil is monitored in real time. If the feedback voltage is equal to zero or close to zero, the exciter power supply circuit is controlled to supply power to the exciter coil. If the feedback voltage still does not increase, it is judged that the exciter motor is faulty and a fault signal is issued.
4. An excitation power supply control circuit for an excitation generator, characterized in that, The control circuit includes an electronic switch circuit, a current-limiting resistor circuit, a microprocessor, and a voltage feedback detection circuit. The electronic switch circuit and the current-limiting resistor circuit are connected in series. The input terminal of the electronic switch circuit is used to connect to the positive terminal of the battery power supply. The end of the current-limiting resistor circuit not connected to the electronic switch circuit is connected to the input terminal of the excitation coil of the exciter. The control terminal of the electronic switch circuit is connected to the power switch control port of the microprocessor. The microprocessor has an engine or exciter rotation detection signal input port to detect whether the engine or exciter is rotating normally. The input terminal of the voltage feedback detection circuit is connected to the connection line between the current-limiting resistor and the exciter coil input terminal of the exciter. The output terminal of the voltage feedback detection circuit is connected to the exciter feedback voltage detection port of the microprocessor. When the system is powered on, the microprocessor detects in real time whether the engine has started or whether the exciter has started rotating. When it detects that the engine has started normally or the exciter has started rotating normally, the microprocessor controls the electronic switch in the electronic switch circuit to conduct, thereby outputting a set current to the exciter coil. After the engine starts, the microprocessor detects the feedback voltage of the excitation coil in real time through the voltage feedback detection circuit. When the feedback voltage is not less than the set voltage, the microprocessor turns off the electronic switch to cut off the power supply current, and the excitation generator enters the self-powered stage of the excitation coil. When the engine is running normally, when the feedback voltage is detected to be zero or close to zero, the microprocessor outputs a 1Hz PWM signal through the power switch control port to control the electronic switch and provide excitation current to the excitation coil of the excitation generator.
5. The excitation power supply control circuit for the excitation generator according to claim 4, characterized in that, A backflow prevention circuit unit is connected in series between the output terminal of the control circuit and the input terminal of the excitation coil.
6. The excitation power supply control circuit for the excitation generator according to claim 4, characterized in that, The electronic switch circuit consists of a switching transistor circuit connected to the control electrode of a power electronic switch, and the two on / off terminals of the power electronic switch are connected in series with a current-limiting resistor circuit.
7. The excitation power supply control circuit for the excitation generator according to claim 4, characterized in that, The current-limiting resistor circuit is used to limit the excitation current supply within a set range by coordinating the battery voltage value with the current-limiting resistor.
8. The excitation power supply control circuit for the excitation generator according to claim 4, characterized in that, The feedback voltage circuit is composed of a voltage divider circuit consisting of series resistors, and the voltage tapping point is set and connected to the corresponding port of the microprocessor.
9. An excitation generator device, wherein the excitation coil of the excitation generator is connected to an excitation power supply control circuit, characterized in that, The excitation power supply control circuit is the control circuit described in any one of claims 4-8.