Jet driving circuit of natural gas engine
By introducing a high-side drive circuit, a low-side drive circuit, a nozzle electromagnetic coil energy feedback circuit, and a current limiting circuit into the natural gas engine injection drive circuit, the problem of large diode conduction loss under low-temperature conditions is solved, energy recovery and utilization are achieved, and the system efficiency and the endurance of the low-voltage battery are improved.
Patent Information
- Application Number
- CN202423077454.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2025-09-26
- Estimated Expiration
- 2034-12-12
AI Technical Summary
The existing natural gas engine injection drive circuit has large conduction losses under low temperature conditions, and the diode reverse recovery current increases, resulting in increased consumption of the low-voltage battery and affecting the endurance time.
The high-side drive circuit, low-side drive circuit, nozzle electromagnetic coil energy feedback circuit and current limiting circuit are adopted. The energy feedback circuit composed of transistors and capacitors replaces the traditional diode energy feedback solution, absorbs the energy generated by the nozzle electromagnetic coil and recycles it.
It effectively reduces circuit loss, prevents damage to circuit components, improves injection system efficiency, and extends the life of low-voltage batteries.
Smart Images
Figure CN223387428U_ABST
Abstract
Description
Technical Field
[0001] The embodiment of the utility model relates to the technical field of natural gas engines, and in particular to an injection drive circuit of a natural gas engine. Background Art
[0002] Natural gas is the third largest natural energy source after coal and oil, and it is abundant in nature. Natural gas not only provides power performance comparable to oil, but also has much less pollution to the atmosphere. When a natural gas engine is working, the natural gas in the gas cylinder is pressure regulated, filtered, and injected into the gas mixer. The natural gas and air are mixed in a certain proportion in the gas mixer and then enter the intake manifold for final ignition and combustion. The reliability of the injection drive circuit plays a key role in the stability of the natural gas engine control system. At present, the existing injection drive circuit solutions are as follows: Figure 1 As shown, the diode-uncontrolled energy feedback method is used, with diode D2 and resistor R2 forming an energy feedback loop. Although this solution is simple to implement, the circuit loss is directly related to the diode conduction parameters. Since the diode voltage drop is relatively large, especially at low temperatures, the diode conduction voltage drop will become larger than at room temperature and high temperature, causing the conduction loss to increase as the ambient temperature decreases. In addition, the reverse recovery current of the diode increases with the ambient temperature, which in turn leads to increased diode reverse recovery loss and reverse voltage stress at high temperatures, increasing the consumption of the low-voltage battery and affecting the battery life of the low-voltage battery. The above problems need to be solved urgently. Utility Model Content
[0003] In order to solve the related technical problems, the present invention provides a natural gas engine injection drive circuit to solve the problems mentioned in the above background technology part.
[0004] To achieve the above objectives, the present invention adopts the following technical solutions:
[0005] An embodiment of the present utility model provides a natural gas engine injection drive circuit, comprising: a high-side drive circuit, a low-side drive circuit, a nozzle electromagnetic coil energy feedback circuit, and a current limiting circuit; a high-voltage input end of the high-side drive circuit is connected to a first terminal of the nozzle electromagnetic coil energy feedback circuit and a drive power supply, a low-voltage input end of the high-side drive circuit is connected to a second terminal of the nozzle electromagnetic coil energy feedback circuit and a drive power supply, an output end of the high-side drive circuit is connected to one end of the nozzle electromagnetic coil, the other end of the nozzle electromagnetic coil is connected to one end of the low-side drive circuit and one end of the current limiting circuit, and the other end of the current limiting circuit is connected to the nozzle electromagnetic coil energy feedback circuit; the other end of the low-side drive circuit is grounded.
[0006] As an optional embodiment, the high-side drive circuit includes a low-voltage input terminal, a high-voltage input terminal, a transistor Q1, a diode D1 and a transistor Q3; the drain of the transistor Q1 is connected to the low-voltage input terminal and the first terminal of the nozzle electromagnetic coil energy feedback circuit, the gate of the transistor Q1 is connected to the injection drive controller, the anode of the diode D1 is connected to the source of the transistor Q1, the cathode of the diode D1 is connected to one end of the nozzle electromagnetic coil and the source of the transistor Q3, the gate of the transistor Q3 is connected to the injection drive controller, the high-voltage input terminal is connected to the drain of the transistor Q1 and the second terminal of the nozzle electromagnetic coil energy feedback circuit.
[0007] As an optional implementation, the low-side drive circuit includes a transistor Q2; the drain of the transistor Q2 is connected to one end of the nozzle electromagnetic coil, the source of the transistor Q2 is grounded, and the gate of the transistor Q2 is connected to the injection drive controller.
[0008] As an optional embodiment, the nozzle electromagnetic coil energy feedback circuit includes a transistor Q4, a capacitor C1, a transistor Q5, a capacitor C2 and a diode D2; the source of the transistor Q4 is connected to one end of the current limiting circuit, the drain of the transistor Q4 is connected to the drain of the transistor Q3 and one end of the capacitor C2, and the other end of the capacitor C2 is grounded; the source of the transistor Q5 is connected to the other end of the current limiting circuit, the drain of the transistor Q5 is connected to the drain of the transistor Q1 and one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
[0009] As an optional embodiment, the current limiting circuit includes a resistor R1 and a resistor R2; wherein the resistor R1 is connected in series between the source of the transistor Q5 and the drain of the transistor Q2; and the resistor R2 is connected in series between the source of the transistor Q4 and the drain of the transistor Q2.
[0010] As an optional implementation, the transistor Q1 , the transistor Q2 , and the transistor Q3 are but not limited to MOS transistors.
[0011] As an optional implementation, the transistor Q4 and the transistor Q5 are but not limited to MOS tubes.
[0012] Compared with the existing natural gas engine injection drive circuit, the natural gas engine injection drive circuit proposed in the embodiment of the utility model can absorb the energy generated by the nozzle electromagnetic coil, effectively prevent the reverse potential of the nozzle electromagnetic coil from causing damage to circuit components, recycle the energy of the nozzle electromagnetic coil, improve the efficiency of the natural gas engine injection system, reduce the consumption of the low-voltage battery in the natural gas engine injection, and increase the service life of the low-voltage battery. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] In order to more clearly illustrate and understand the technical solutions in the embodiments of the present invention, a brief introduction is given below to the background technology of the present invention and the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.
[0014] Figure 1 It is a structural diagram of an existing jet drive circuit;
[0015] Figure 2 A structural diagram of a natural gas engine injection drive circuit provided by an embodiment of the utility model;
[0016] Figure 3 A schematic diagram of the control timing of the driving circuit provided in an embodiment of the present utility model;
[0017] Figure 4 A schematic diagram of the injection waveform provided by an embodiment of the present utility model;
[0018] Figure 5 This is a schematic diagram of the working status of the driving circuit provided by an embodiment of the utility model in different stages. DETAILED DESCRIPTION
[0019] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved more clearly, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.
[0020] Example 1
[0021] In this embodiment, the natural gas engine injection drive circuit includes: a high-side drive circuit, a low-side drive circuit, a nozzle electromagnetic coil energy feedback circuit and a current limiting circuit; the high-voltage input end of the high-side drive circuit is connected to the first terminal of the nozzle electromagnetic coil energy feedback circuit and the drive power supply, the low-voltage input end of the high-side drive circuit is connected to the second terminal of the nozzle electromagnetic coil energy feedback circuit and the drive power supply, the output end of the high-side drive circuit is connected to one end of the nozzle electromagnetic coil, the other end of the nozzle electromagnetic coil is connected to one end of the low-side drive circuit and one end of the current limiting circuit, and the other end of the current limiting circuit is connected to the nozzle electromagnetic coil energy feedback circuit; the other end of the low-side drive circuit is grounded.
[0022] For example, Figure 2As shown, the high-side drive circuit includes a low-voltage input terminal, a high-voltage input terminal, a transistor Q1, a diode D1, and a transistor Q3; the drain of the transistor Q1 is connected to the low-voltage input terminal and the first terminal of the nozzle electromagnetic coil energy feedback circuit, the gate of the transistor Q1 is connected to the injection drive controller, the anode of the diode D1 is connected to the source of the transistor Q1, the cathode of the diode D1 is connected to one end of the nozzle electromagnetic coil and the source of the transistor Q3, the gate of the transistor Q3 is connected to the injection drive controller, the high-voltage input terminal is connected to the drain of the transistor Q1, and the second terminal of the nozzle electromagnetic coil energy feedback circuit.
[0023] For example, Figure 2 As shown, the low-side drive circuit includes a transistor Q2; the drain of the transistor Q2 is connected to one end of the nozzle electromagnetic coil, the source of the transistor Q2 is grounded, and the gate of the transistor Q2 is connected to the injection drive controller.
[0024] For example, Figure 2 As shown, the nozzle electromagnetic coil energy feedback circuit includes a transistor Q4, a capacitor C1, a transistor Q5, a capacitor C2 and a diode D2; the source of the transistor Q4 is connected to one end of the current limiting circuit, the drain of the transistor Q4 is connected to the drain of the transistor Q3 and one end of the capacitor C2, and the other end of the capacitor C2 is grounded; the source of the transistor Q5 is connected to the other end of the current limiting circuit, the drain of the transistor Q5 is connected to the drain of the transistor Q1 and one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
[0025] For example, Figure 2 As shown, the current limiting circuit includes a resistor R1 and a resistor R2; wherein the resistor R1 is connected in series between the source of the transistor Q5 and the drain of the transistor Q2; and the resistor R2 is connected in series between the source of the transistor Q4 and the drain of the transistor Q2.
[0026] In this embodiment, if Figure 2 As shown, the transistors Q1, Q2 and Q3 are but not limited to MOS tubes. Figure 2 As shown, the transistors Q4 and Q5 are but not limited to MOS tubes. It is worth mentioning that, depending on the actual application, the transistors Q4 and Q5 can also be diodes.
[0027] Specifically, such as Figures 3 to 5The operating process of the natural gas engine injection drive circuit proposed in this embodiment is as follows: t = 0 to t1: Transistors Q3 and Q2 are turned on. Current flows from the 48V power supply (the driving power supply) through the nozzle solenoid coil and transistor Q2 of the low-side driver circuit to the nozzle solenoid coil. At this time, the nozzle solenoid coil current is characterized by high current and a rapid current rise slope, requiring a large amount of energy. Therefore, the energy is provided by the 48V power supply. t = t1 to t2: Transistor Q2 is turned off. While transistor Q3 is in the off state, the energy in the nozzle solenoid coil is fed back through the nozzle solenoid coil Q4, capacitor C1, and transistor D2 to form a nozzle solenoid coil energy feedback circuit. Resistor R2 in the current limiting circuit provides current limiting and damping. t = t2 to t3: The nozzle solenoid coil current only needs to be maintained. Therefore, the current demand is much lower than during the 0 to t1 period, but the coil current needs to be maintained for a period of time. Therefore, using a 24V power supply can meet the nozzle solenoid coil current requirements. t = t3-t4: During this time, transistor Q2 is turned off, and transistor Q1 is in the process of being turned off. Energy in the nozzle solenoid coil is fed back through transistor Q5, capacitor C2, and diode D2 to form a nozzle solenoid coil energy feedback circuit. Resistor R1 in the current limiting circuit provides current limiting and damping. Alternatively, in this embodiment, transistor Q2 can be turned on while transistors Q1 and Q3 are turned off, allowing the nozzle solenoid coil energy to be dissipated through diode D2 and heat generation in the coil.
[0028] The natural gas engine injection drive circuit proposed in this embodiment of the utility model replaces the traditional diode energy feedback scheme with a nozzle electromagnetic coil energy feedback circuit. This effectively utilizes the advantages of transistors such as low on-resistance, low switching loss, and low reverse recovery loss to achieve control of feedback energy and improve the efficiency of the natural gas engine injection system. The natural gas engine injection drive circuit proposed in this embodiment of the utility model can absorb the energy generated by the nozzle electromagnetic coil, effectively preventing damage to circuit components caused by the reverse potential of the nozzle electromagnetic coil. It recycles the energy of the nozzle electromagnetic coil, improves the efficiency of the natural gas engine injection system, reduces the consumption of the low-voltage battery in the natural gas engine injection, and increases the low-voltage battery life.
[0029] Note that the above are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions are possible for those skilled in the art without departing from the scope of protection of the present invention. Therefore, while the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the scope of the present invention. The scope of the present invention is determined by the scope of the appended claims.
Claims
1. A natural gas engine injection drive circuit, characterized in that: include: High-side drive circuit, low-side drive circuit, nozzle electromagnetic coil energy feedback circuit and current limiting circuit; The high-voltage input end of the high-side drive circuit is connected to the first terminal of the nozzle electromagnetic coil energy feedback circuit and the drive power supply, the low-voltage input end of the high-side drive circuit is connected to the second terminal of the nozzle electromagnetic coil energy feedback circuit and the drive power supply, the output end of the high-side drive circuit is connected to one end of the nozzle electromagnetic coil, the other end of the nozzle electromagnetic coil is connected to one end of the low-side drive circuit and one end of the current limiting circuit, the other end of the current limiting circuit is connected to the nozzle electromagnetic coil energy feedback circuit; the other end of the low-side drive circuit is grounded.
2. The natural gas engine injection drive circuit according to claim 1, characterized in that: The high-side drive circuit includes a low-voltage input terminal, a high-voltage input terminal, a transistor Q1, a diode D1, and a transistor Q3; the drain of the transistor Q1 is connected to the low-voltage input terminal and the first terminal of the nozzle electromagnetic coil energy feedback circuit, the gate of the transistor Q1 is connected to the injection drive controller, the anode of the diode D1 is connected to the source of the transistor Q1, the cathode of the diode D1 is connected to one end of the nozzle electromagnetic coil and the source of the transistor Q3, the gate of the transistor Q3 is connected to the injection drive controller, the high-voltage input terminal is connected to the drain of the transistor Q1, and the second terminal of the nozzle electromagnetic coil energy feedback circuit.
3. The natural gas engine injection drive circuit according to claim 2, characterized in that: The low-side drive circuit includes a transistor Q2; the drain of the transistor Q2 is connected to one end of the nozzle electromagnetic coil, the source of the transistor Q2 is grounded, and the gate of the transistor Q2 is connected to the injection drive controller.
4. The natural gas engine injection drive circuit according to claim 3, characterized in that: The nozzle electromagnetic coil energy feedback circuit includes a transistor Q4, a capacitor C1, a transistor Q5, a capacitor C2 and a diode D2; the source of the transistor Q4 is connected to one end of the current limiting circuit, the drain of the transistor Q4 is connected to the drain of the transistor Q3 and one end of the capacitor C2, and the other end of the capacitor C2 is grounded; the source of the transistor Q5 is connected to the other end of the current limiting circuit, the drain of the transistor Q5 is connected to the drain of the transistor Q1 and one end of the capacitor C1, and the other end of the capacitor C1 is grounded.
5. The natural gas engine injection drive circuit according to claim 4, characterized in that: The current limiting circuit includes a resistor R1 and a resistor R2; wherein the resistor R1 is connected in series between the source of the transistor Q5 and the drain of the transistor Q2; and the resistor R2 is connected in series between the source of the transistor Q4 and the drain of the transistor Q2.
6. The natural gas engine injection drive circuit according to claim 5, characterized in that: The transistor Q1 , the transistor Q2 , and the transistor Q3 are but not limited to MOS tubes.
7. The natural gas engine injection drive circuit according to any one of claims 4 to 6, characterized in that: The transistor Q4 and the transistor Q5 are but not limited to MOS tubes.