Anti-creeping phase signal acquisition circuit of multi-phase generator
By designing a leakage-proof signal acquisition circuit in the electronic control system of a multiphase generator, and using a combined structure of capacitors and diodes, the problem of leakage interference in the stator winding signal is solved, high sensitivity and reliability of signal acquisition are achieved, the circuit structure is simplified and the cost is reduced.
Patent Information
- Application Number
- CN202411921515.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-25
- Publication Date
- 2025-04-08
AI Technical Summary
In the existing electronic control system of multiphase generators, the stator winding signal acquisition circuit fails to effectively control the leakage phenomenon in the generator stator winding signal, resulting in signal abnormalities and control errors.
A multi-phase generator leakage-proof signal acquisition circuit is designed, and a combination of a first capacitor, a first diode and a second diode is used to eliminate interference caused by weak DC leakage through the connection method of capacitor and diode, and a current limiting resistor and additional capacitor are introduced when necessary to optimize signal acquisition.
It improves the sensitivity of signal acquisition, eliminates leakage interference, ensures the reliability of signal processing, simplifies the circuit structure, reduces costs, and improves the operating reliability of the generator regulator circuit.
Smart Images
Figure CN119780457A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of generator electronic control, and in particular relates to a multi-phase generator anti-leakage phase signal acquisition circuit. Background Art
[0002] Multiphase generators are the mainstream generators today, and vehicle generators are all multiphase generators. Existing vehicle generators are AC synchronous generators, which have three-phase or six-phase stator windings. The circuit part that controls the excitation of the generator excitation winding is called a voltage regulator. It also includes the need to collect a signal from a certain phase in the stator winding to identify the generator speed or to control the charging indicator light. Figure 1 As shown, the three-phase generator has three-phase stator windings (including A-phase stator winding, B-phase stator winding and C-phase stator winding). The dotted frame part represents the internal structure of the voltage regulator. The three-phase windings A, B, and C are connected in star shape. Most of the time, only the phase signal of one phase needs to be collected. For example, when collecting the B-phase signal, the collection point is at the lead output end of the B-phase stator winding of the AC generator, because the lead output end is simultaneously connected to the connection point of the positive diode D12 and the negative diode D16 of the rectifier bridge. The diodes D12 and D16 are used to perform bidirectional rectification on the B-phase AC voltage when the generator rotates to generate electricity. When the generator stops rotating, there is no voltage output at the lead output end of the B-phase stator winding. Because the diodes D12 and D16 are both cut off, the output end of this phase is in a high impedance state of 0V with respect to the common ground of the system. In actual operation, because the generator is in the common harsh environment of high-speed airflow in the engine compartment (when driving at high speed and the generator fan rotates at high speed), high temperature baking (a lot of heat is accumulated in the engine compartment), high dust (such as smoke and dust weather or dirt roads), high humidity (rainy days or flooded roads), etc., the rectifier bridge diode itself is prone to weak leakage, and the insulating components may also leak due to moisture and dust accumulation. Because the positive plate of the generator rectifier bridge is connected to the positive pole of the battery, even when the generator is not generating electricity, such leakage phenomenon (such as weak leakage inside D12 or weak leakage due to moisture and dust accumulation outside) will cause the B phase winding to accidentally output a DC potential, which will interfere with the conventional phase signal acquisition circuit, and then cause signal abnormality in its subsequent control circuit, such as Figure 2 and Figure 3 As shown in the figure, the dotted box part is the conventional "phase signal acquisition circuit". When the phase signal point P (P is the prefix of phase) has a DC voltage from the leakage resistor, it will send an error signal to the subsequent processing circuit through R11 and D4, such as abnormal extinguishing of the charging indicator light, poor speed signal, etc. Figure 1 and Figure 2In the existing public technologies, there is no phase signal acquisition circuit that can effectively control the phase signal leakage phenomenon of the generator stator winding. Therefore, it is necessary to design a multi-phase generator phase signal acquisition circuit that is reliable in operation and has a relatively simple circuit. Summary of the invention
[0003] The present invention provides a multi-phase generator anti-leakage phase signal acquisition circuit, which is used in a multi-phase generator electronic control system, and is characterized in that it includes a first capacitor, a first diode and a second diode;
[0004] When the multi-phase generator anti-leakage phase signal acquisition circuit outputs a DC signal, it also includes a second capacitor; when the multi-phase generator anti-leakage phase signal acquisition circuit outputs a pulse signal, it also includes a first resistor;
[0005] One end of the first capacitor is used to be connected to a phase terminal of the armature winding of the multi-phase generator, and the other end of the first capacitor is simultaneously connected to the cathode of the first diode and the anode of the second diode, the cathode of the second diode is connected to the system ground through the second capacitor or through the first resistor, and the cathode of the second diode serves as the output end of the anti-leakage phase signal acquisition circuit to provide the acquired generator phase signal to the processing circuit of the electronic control system of the multi-phase generator.
[0006] Furthermore, the present invention also provides a multi-phase generator anti-leakage phase signal acquisition circuit, which is special in that a current limiting resistor is connected in series in the second diode circuit, and the current limiting resistor is connected in series to the positive circuit or the negative circuit of the second diode.
[0007] Furthermore, the present invention also provides a multi-phase generator anti-leakage phase signal acquisition circuit, which is special in that one end of the first capacitor used for connecting to the phase terminal is also connected to the system ground by a third capacitor.
[0008] Furthermore, the present invention also provides an anti-leakage phase signal acquisition circuit, which is special in that the output end of the anti-leakage phase signal acquisition circuit is connected to the pulse processing circuit in the processing circuit of the multi-phase generator electronic control system.
[0009] Furthermore, the present invention also provides a multi-phase generator anti-leakage phase signal acquisition circuit, which is special in that the output end of the anti-leakage phase signal acquisition circuit is connected to the indicator light processing circuit in the processing circuit of the multi-phase generator electronic control system.
[0010] Furthermore, the present invention also provides a multi-phase generator anti-leakage phase signal acquisition circuit, which is special in that the indicator light processing circuit adopts a transistor control circuit.
[0011] Furthermore, the present invention also provides a multi-phase generator anti-leakage phase signal acquisition circuit, which is special in that the indicator light processing circuit adopts a control circuit combining a comparator chip and a transistor.
[0012] The multi-phase generator phase signal acquisition circuit structure adopted in the technical solution of the present invention is very sensitive to the AC component in the phase terminal DC signal, which improves the acquisition sensitivity. It can also eliminate the interference caused by weak DC leakage in the generator phase signal loop, provide reliability guarantee for the subsequent phase signal processing, and realize the simplification of the structure of the phase signal preprocessing, the reduction of volume, and the reduction of structural cost and process cost. It solves the problem of simplifying the circuit structure of the generator regulator to a certain extent and also improves the operation reliability. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 The present invention is a schematic diagram of the structure of the overall circuit structure of the generator and the voltage regulator in the prior art.
[0014] Figure 2 It is one of the schematic diagrams of the phase signal acquisition circuit and indicator light control circuit in the prior art.
[0015] Figure 3 This is the second schematic diagram of the phase signal acquisition circuit and indicator light control circuit in the prior art.
[0016] Figure 4 The present invention provides a schematic diagram of a phase signal acquisition basic circuit and an indicator light control circuit structure with a DC signal output.
[0017] Figure 5 It is a schematic diagram of the structure of a phase signal acquisition basic circuit and a pulse processing circuit with pulse signal output provided by an embodiment of the present invention.
[0018] Figure 6 The present invention provides a schematic diagram of a phase signal acquisition circuit and an indicator light control circuit structure with optimized output impedance.
[0019] Figure 7 The present invention provides a schematic diagram of a phase signal acquisition circuit and an indicator light control circuit structure with optimized anti-interference performance.
[0020] Figure 8 The present invention provides a schematic diagram of a phase signal acquisition circuit and an indicator light control circuit structure with optimized input impedance.
[0021] Fig. 9 It is the measured waveform of the normal output of the generator phase terminal when there is no leakage in the rectifier bridge.
[0022] Fig.10This is a measured waveform diagram of the output signal of the "phase signal acquisition circuit" of Example 2 of the present invention when the generator is at low speed.
[0023] Fig.11 This is a measured waveform diagram of the output signal of the "phase signal acquisition circuit" of Example 2 of the present invention when the generator is at medium speed.
[0024] Fig.12 This is a measured waveform diagram of the output signal of the "phase signal acquisition circuit" of Example 1 of the present invention when the generator is at low speed. DETAILED DESCRIPTION
[0025] The purpose of the present invention is to design a highly sensitive acquisition circuit for phase signals of a multi-phase generator, which can eliminate the interference caused by weak DC leakage in the phase signal loop of the generator, provide reliability guarantee for the processing of subsequent phase signals, and realize the simplification of the structure of phase signal preprocessing, reduction of volume, reduction of structural cost and process cost, solve the problem of simplifying the circuit structure of the generator regulator to a certain extent, and improve the operational reliability.
[0026] The embodiment of the present invention provides a multi-phase generator anti-leakage phase signal acquisition circuit of the present invention, which is used in the multi-phase generator electronic control system.
[0027] Example 1
[0028] like Figure 4 As shown, the circuit includes a phase signal acquisition circuit (101) within a dotted frame and an indicator light processing circuit outside the dotted frame, the acquisition circuit includes a first capacitor (C11), a first diode (D11), a second diode (D4) and a second capacitor (C3), one end of the first capacitor (C11) is used to connect to a phase (B phase output) terminal P (Phase) of the armature winding of the multi-phase generator, see Figure 1 The first capacitor (C11) is connected to the P (Phase) point of the output end of the B-phase winding; the other end of the first capacitor (C11) is simultaneously connected to the cathode of the first diode (D11) and the anode of the second diode (D4); the cathode of the second diode (D4) is connected to the system ground (E) through the second capacitor (C3); the cathode of the second diode (D4) serves as the output end of the anti-leakage phase signal acquisition circuit, and the output end is used to provide the acquired generator phase signal to the processing circuit of the electronic control system of the multi-phase generator.
[0029] Its working principle is: Combined with Figure 1When the AC generator is in the off state, the positive plate on the rectifier bridge is connected to the positive electrode of the battery, and the negative plate is connected to the negative electrode of the battery. These basic connection relationships are consistent with the technical solution of the present invention. When the generator is turned on by the ignition switch and is in standby mode, that is, the generator is ready to generate electricity, this state is called the vehicle's "KOEO" (Key on engine off), and the charging indicator light is on. At this time, under normal conditions, the phase terminal P should have no DC voltage output, nor AC voltage or pulse voltage output. Figure 4 At this time, there is no voltage output at the lower end of the first capacitor (C11), and a low-level signal is provided to the first end of the post-processing circuit comparator A2 through resistors (R13) and (R14). The second end of comparator A2 obtains a reference voltage (Vref2), so the comparator can be set to a high-impedance working mode at this time. The base resistor (R15) provides a base bias current for the transistor Q3 to turn on, and controls the indicator light connected to it to light up. Therefore, the indicator light is on when no power is generated. When the engine runs and drives the generator to run, the stator winding will generate an induced electromotive force, and the phase end P will have a pulsating voltage output. The measured voltage waveform is as follows: Fig. 9 As shown, the pulsating voltage jumps upward with 0V as the minimum value, and its pulse voltage will be coupled to the connection point of the first diode (D11) and the second diode (D4) through the first capacitor (C11). When the pulsating voltage is in the positive half cycle, it will charge the second capacitor (C3) through D4. When it is in the negative half cycle, the first diode (D11) provides a discharge circuit for C11, so that C11 discharges and charges in reverse. When the next positive half axis is reversely charged, the voltage is superimposed on the induced electromotive force of the stator winding in the same direction to obtain a higher voltage. This voltage charges C3 through D4 to increase its potential. Therefore, the pulse voltage signals of the positive and negative half cycles can be fully utilized. Such a phase signal acquisition circuit structure is very sensitive to the AC component in the DC signal of the phase terminal, which improves the sensitivity of sampling the phase point P signal. When the capacity of capacitor C3 is large enough, a relatively smooth DC voltage signal can be obtained at the upper pole of C3, and its measured voltage waveform is as follows: Fig.12 As shown in the figure, the signal waveform is measured when C3 is a small 0.1μF capacitor. Although it is mixed with pulsation components, the minimum value of the pulsation amplitude is still greater than 0V. This can be seen by comparing Fig. 9 By comparing the "0 potential point" reflected in its waveform, it is confirmed that the DC voltage component contained in it provides a reliable DC voltage signal source for the post-processing circuit. Figure 9-12The test was conducted under the same calibration state of the same oscilloscope and the same acquisition circuit, and the waveform coordinate system parameters are consistent. When the rectifier bridge DC leakage occurs, when the positive power from the battery reaches the phase sampling point P through the leakage resistor, regardless of whether the generator is running to generate electricity, the leakage current generated by the leakage resistor cannot be transmitted to the next stage through the first capacitor C11, so it will not be like Figure 2 and Figure 3 In this way, the subsequent signal processing circuit will not be affected by the incorrect control of the indicator light or give the subsequent stage a wrong signal.
[0030] It is easy to understand that the subsequent processing circuit may not use the comparator (A2) but may use Figure 1 The transistor output method in the prior art shown controls the indicator light.
[0031] Example 2
[0032] like Figure 5 As shown, the circuit includes a phase signal acquisition circuit (101) within a dotted frame and an indicator light processing circuit outside the dotted frame, including a first capacitor (C11), a first diode (D11), a second diode (D4) and a first resistor (R13), one end of the first capacitor (C11) is used to connect to a phase (B phase output) terminal P (Phase) of the armature winding of the multi-phase generator, the other end of the first capacitor (C11) is simultaneously connected to the cathode of the first diode (D11) and the anode of the second diode (D4), the cathode of the second diode (D4) is connected to the system ground (E) through the first resistor (R13), and the cathode of the second diode (D4) is used as the output end of the anti-leakage phase signal acquisition circuit to provide the pulse processing circuit (A2) of the multi-phase generator electronic control system with the acquired generator phase signal.
[0033] Similar to the working principle of Example 1, it is not difficult to understand from the above analysis that when the generator is not generating electricity, there is no DC voltage signal output at the non-grounded end of the first resistor (R13), and there is no AC voltage signal output. When the generator is generating electricity, a pulse voltage signal will be obtained at the upper end of the resistor (R13). When the generator is at a low speed (500-1000RPM), the measured voltage waveform is as follows: Fig.10 As shown, when the generator is at medium speed (4000-5000RPM), the measured voltage waveform is as follows Fig.11 As shown, the amplitude of the pulse voltage signal will fluctuate with the generator output voltage, and the frequency of the pulse voltage signal will also change with the generator speed. In this way, the pulse signal with both frequency and amplitude changes enters the subsequent circuit for processing, such as Figure 5The signal enters the shaping circuit (i.e., the pulse processing circuit A2, which can use a Schmitt trigger or a clipped amplifier circuit for signal processing), and A2 outputs a rectangular wave signal, which can provide a generator speed signal for the subsequent microprocessor to identify the generator speed and control the charging indicator light. Of course, it can also be used directly by the subsequent stage to control the charging indicator light, which depends on the adaptive design and matching of the vehicle and the generator electronic control system. Similarly, when the rectifier bridge leaks, when the positive power from the battery reaches the phase sampling point P through the leakage resistor, regardless of whether the generator is running to generate electricity, the leakage current generated by the leakage resistor cannot be transmitted to the subsequent stage through the first capacitor C11, so it will not be like Figure 2 and Figure 3 Doing so will not affect the subsequent signal processing circuit and will not erroneously control the indicator light.
[0034] Example 3
[0035] like Figure 6 As shown, this embodiment is similar to the above-mentioned embodiment 1, and a first resistor (R13) is added to respond to and optimize the output impedance of the generator phase signal acquisition circuit, and provide a charge discharge loop for capacitor C3 to adapt to the responsiveness of the circuit. Even when the capacity of C3 is low, a pulse signal after voltage doubling can be obtained at the upper pole of C3, providing a reliable pulse voltage signal source for the subsequent processing circuit, such as providing it to the subsequent stage for frequency detection, etc.
[0036] Example 4
[0037] like Figure 7 As shown, in Figure 4 or Figure 5 On the basis of the illustrated embodiment, the phase signal introduction point is subjected to noise elimination processing, and a third capacitor (C2) is added, one end of which is connected to the system ground, and the other end is connected to one end of the first capacitor connected to the phase terminal P. Because many electrical devices in modern vehicles are connected to the vehicle system, such as various chargers with radio frequency interference, injection pulse width or ignition pulse interference, when some high-frequency interference enters the phase terminal P in the generator system, the third capacitor (C2) bypasses the high-frequency interference signal to the ground, so as to improve the system's anti-interference ability and make its operation stable and reliable.
[0038] Example 5
[0039] like Figure 8 As shown, this embodiment Figure 7 Based on the illustrated embodiment, a current limiting resistor (R16) is added to respond to and optimize the input impedance of the generator phase signal acquisition circuit to improve system stability.
[0040] The above embodiments are only for describing the technical ideas of the present invention. The circuit structure adopted by the technical solution of the present invention can eliminate the interference caused by even weak DC leakage in the generator phase signal circuit, provide reliability guarantee for the subsequent processing of phase signals, achieve high sensitivity and structural simplification, volume reduction, and reduce structural and process costs of phase signal preprocessing, solve the problem of simplifying the circuit structure of the generator regulator to a certain extent, and improve operational reliability.
[0041] The above-mentioned embodiments are only used to describe the technical solutions of the present invention, and are not the only embodiments. Any embodiments obtained by modification with equivalent effect substitution etc. fall within the scope of variation of the present invention, and the scope of variation of the present invention is limited by the attached claims.
Claims
1. A multi-phase generator anti-leakage phase signal acquisition circuit, used in a multi-phase generator electronic control system, characterized in that: comprising a first capacitor, a first diode and a second diode, When the multi-phase generator anti-leakage phase signal acquisition circuit outputs a DC signal, it also includes a second capacitor; when the multi-phase generator anti-leakage phase signal acquisition circuit outputs a pulse signal, it also includes a first resistor; One end of the first capacitor is used to be connected to a phase terminal of the armature winding of the multi-phase generator, and the other end of the first capacitor is simultaneously connected to the cathode of the first diode and the anode of the second diode, the cathode of the second diode is connected to the system ground through the second capacitor or through the first resistor, and the cathode of the second diode serves as the output end of the anti-leakage phase signal acquisition circuit to provide the acquired generator phase signal to the processing circuit of the electronic control system of the multi-phase generator.
2. The multi-phase generator anti-leakage phase signal acquisition circuit according to claim 1 is characterized in that: A current limiting resistor is connected in series in the second diode loop, and the current limiting resistor is connected in series to the positive electrode loop or the negative electrode loop of the second diode.
3. The multi-phase generator anti-leakage phase signal acquisition circuit according to claim 1, characterized in that: One end of the first capacitor connected to the phase terminal is also connected to the system ground via a third capacitor.
4. The multi-phase generator anti-leakage phase signal acquisition circuit according to claim 1, characterized in that: The output end of the anti-leakage phase signal acquisition circuit is connected to the pulse processing circuit in the processing circuit of the multi-phase generator electronic control system.
5. The multi-phase generator anti-leakage phase signal acquisition circuit according to claim 1, characterized in that: The output end of the anti-leakage phase signal acquisition circuit is connected to the indicator light processing circuit in the processing circuit of the multi-phase generator electronic control system.
6. The multi-phase generator anti-leakage phase signal acquisition circuit according to claim 5, characterized in that: The indicator light processing circuit adopts a transistor control circuit.
7. The multi-phase generator anti-leakage phase signal acquisition circuit according to claim 5, characterized in that: The indicator light processing circuit adopts a control circuit combining a comparator chip and a transistor.