Electric hydraulic system capable of directly carrying new energy high-voltage battery

Abstract

The utility model discloses an electric hydraulic system capable of directly carrying a new energy high-voltage battery, which comprises a power unit used for converting mechanical energy into hydraulic energy, the power unit comprises a motor, a central valve block is arranged between a gear pump and the motor, and the central valve block is provided with a first oil port and a second oil port; the hydraulic control unit is used for controlling and changing a hydraulic oil path, and the hydraulic control valve group comprises a plurality of electromagnetic valves; the electric control unit is used for converting the 110V high-voltage direct current output by the power supply into 80V alternating current required by the alternating current motor and comprises a controller, and the controller is electrically connected with the solid-state relay and the contactor; the system provided by the utility model can be directly carried on a DC high-voltage power supply of more than 96V; the problems of short circuit and electric spark generated when the direct-current high-voltage power supply starts the electric hydraulic system are solved; the problem that the whole circuit system elements are interfered and damaged due to back electromotive force generated by power failure of the electric hydraulic system in a high-voltage direct-current circuit is solved.

Description

Technical Field

[0001] This utility model relates to the technical field of hydraulic and electrical equipment, and in particular to an electric hydraulic system that can be directly equipped with a new energy high-voltage battery. Background Technology

[0002] Traditional construction machinery, sanitation vehicles, and commercial vehicles primarily rely on one or two 12V lead-acid batteries to power their entire electrical system, with the engine generating electricity to charge the batteries. Therefore, most electrical components in these vehicles are 12V or 24V, and the motor-driven hydraulic systems are also mostly 24V or 12V. However, with the replacement of traditional gasoline vehicles by new energy vehicles, the electro-hydraulic systems of traditional gasoline vehicles can no longer be directly applied to current new energy vehicles. Currently, the mainstream new energy vehicle batteries in China are high-voltage lithium batteries, with voltages mostly above 100V DC, and large mining trucks and construction machinery vehicles reaching above 300V. Under the trend of new energy development, an electro-hydraulic system that can be directly integrated with high-voltage DC batteries is urgently needed by the market.

[0003] For electric hydraulic systems to be directly integrated into new energy vehicles, the first challenge is the selection of the motor. Most DC motors on the market are below 96V, so to directly integrate them into a DC vehicle electrical system above 96V, a matching high-voltage DC motor is needed, or a system capable of converting high-voltage DC power to the required motor voltage. Secondly, traditional gasoline vehicles use lead-acid batteries with low-voltage power supplies of 12V and 24V. However, the high-voltage DC power supplies in new energy vehicles generate a huge current upon activation, essentially a short circuit. Protecting the electrical components within the electric hydraulic system is another technical challenge. Finally, the voltage requirements of new energy vehicles are highly variable, with a wide voltage range. Ensuring widespread applicability to most vehicle models is another crucial technical issue. Utility Model Content

[0004] The main objective of this invention is to provide an electric hydraulic system that can be directly equipped with a new energy high-voltage battery, thereby solving existing technical problems.

[0005] To achieve the above objectives, this utility model provides an electric hydraulic system that can be directly equipped with a new energy high-voltage battery, comprising:

[0006] A power unit is used to convert mechanical energy into hydraulic energy. The power unit includes a motor, which is connected to a gear pump via a coupling. A central valve block is provided between the gear pump and the motor. The central valve block is provided with a first oil port and a second oil port. The gear pump is located in a hydraulic oil tank.

[0007] A hydraulic control unit is used to control and change the hydraulic oil circuit. The hydraulic control unit is located on the central valve block and includes a hydraulic control valve group, which includes multiple solenoid valves.

[0008] The electrical control unit is used to convert the 110V high-voltage DC power output from the power supply into the 80V AC power required by the AC motor. It includes a controller, which is electrically connected to a solid-state relay and a contactor. The solid-state relay and the contactor control the on / off state of the control circuit and the main power supply circuit, respectively.

[0009] Furthermore, the first oil port is connected to the hydraulic oil tank through the first oil circuit, and the first oil circuit is equipped with a first solenoid valve and a check valve. The second oil port is connected to the hydraulic oil tank through the second oil circuit, and the second oil circuit is equipped with a second solenoid valve and a third solenoid valve. The first oil circuit and the second oil circuit are interconnected.

[0010] Furthermore, the first solenoid valve in the first oil circuit and the second and third solenoid valves in the second oil circuit are all two-position two-way solenoid valves.

[0011] Furthermore, one of the first solenoid valve and the second solenoid valve is a bidirectional shut-off solenoid valve.

[0012] Furthermore, the first oil line has a branch line with an overflow circuit connected to the hydraulic oil tank, and the overflow circuit is equipped with an overflow valve.

[0013] Furthermore, a throttle valve is provided on the second oil line.

[0014] Furthermore, a 2 kΩ 20W pre-charge resistor is connected in parallel to the main contacts of the contactor.

[0015] Furthermore, a 1N5408 freewheeling diode is connected in parallel with the coil of the contactor, and the positive and negative terminals of the diode are opposite to those of the control power supply.

[0016] Furthermore, it also includes a remote control receiver for remotely controlling the operation of the electro-hydraulic system.

[0017] Furthermore, the motor is an AC asynchronous motor.

[0018] The beneficial effects of this utility model are reflected in:

[0019] 1. This application can be directly installed on new energy vehicles, so that new energy vehicles do not need to be equipped with an additional 12V or 24V power supply, simplifying the vehicle body structure and reducing the manufacturing cost;

[0020] 2. According to the heat formula Q=I²R, the greater the current I, the greater the heat generation capacity of the circuit. For motors of the same power, according to the formula P=UI, the power P is the same, the greater the voltage U, the smaller the current I. Therefore, for the same 3KW motor, the current required by an 80V motor is much smaller than that of a 24V or 12V motor. Consequently, the motor generates less heat, which means that the electric hydraulic system equipped with the motor has a longer working period and a higher safety factor.

[0021] 3. Traditional electric hydraulic systems use DC brushed motors. The brushes of DC brushed motors generate a lot of heat and noise when running at high speeds. In contrast, the electric hydraulic system of this application uses an AC asynchronous motor with a noise level of about 75 decibels, which is much lower than that of DC brushed motors.

[0022] 4. This application is equipped with a remote control receiver, which can be matched with a remote control transmitter to achieve remote control, and users do not need to design an additional control module.

[0023] 5. The input voltage of the controller in this application can be adapted to 48-120V DC power supply, and can achieve full coverage of new energy vehicle models when matched with controllers of different specifications.

[0024] 6. This application is equipped with a high-voltage pre-charge resistor, which avoids electric sparks when the high-voltage power supply is started, thus improving safety performance.

[0025] 7. The AC asynchronous motor used in this application has a speed drop of about 150 to 200 r / min as the load increases, while the DC brushed motors in traditional 12V and 24V electro-hydraulic systems have a speed drop range of 300 to 2000 r / min. Therefore, the output flow of the high-pressure electro-hydraulic system is more stable, and the motion control accuracy and stability of the actuator are higher. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of this utility model;

[0027] Figure 2 This is a schematic diagram of the hydraulic principle of this utility model;

[0028] Figure 3 This is a schematic diagram of the electrical principle of this utility model;

[0029] Figure 4 This is a schematic diagram of the principle of the remote control receiver of this utility model.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Motor; 2. Gear pump; 3. Central valve block; 31. First oil port; 32. Second oil port; 4. Hydraulic oil tank; 5. Hydraulic control valve group; 6. Controller; 7. Solid state relay; 8. Contactor; 9. First solenoid valve; 10. Check valve; 11. Second solenoid valve; 12. Third solenoid valve; 13. Relief valve; 14. Throttle valve; 15. Remote control receiver; 16. Inlet filter; a. First oil circuit; b. Second oil circuit; c. Relief circuit. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present utility model, and not all of them. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.

[0033] Please see Figure 1 This utility model provides an electric hydraulic system that can be directly equipped with a new energy high-voltage battery, comprising:

[0034] The power unit is used to convert mechanical energy into hydraulic energy. The power unit includes a motor 1, which is connected to a gear pump 2 via a coupling. A central valve block 3 is provided between the gear pump 2 and the motor 1. The central valve block 3 is provided with a first oil port 31 and a second oil port 32. The gear pump 2 is located in the hydraulic oil tank 4.

[0035] The hydraulic control unit is used to control and change the hydraulic oil circuit. The hydraulic control unit is located on the central valve block 3 and includes a hydraulic control valve group 5, which includes multiple solenoid valves.

[0036] The electrical control unit is used to convert the 110V high-voltage DC power output from the power supply into the 80V AC power required by the AC motor. It includes a controller 6, which is electrically connected to a solid-state relay 7 and a contactor 8. The solid-state relay 7 and the contactor 8 control the on / off state of the control circuit and the main power supply circuit, respectively.

[0037] The system in this embodiment can be directly mounted on a DC high-voltage power supply of 96V or above; it solves the problem of short circuits and electric sparks when the DC high-voltage power supply starts the electric hydraulic system; and it solves the problem of back electromotive force generated when the electric hydraulic system is interrupted in the high-voltage DC circuit, which interferes with and damages the components of the entire circuit system.

[0038] In one embodiment, please refer to Figure 2The first oil port 31 is connected to the hydraulic oil tank 4 through the first oil passage a. The first oil passage a is equipped with a first solenoid valve 9 and a check valve 10. The second oil port 32 is connected to the hydraulic oil tank 4 through the second oil passage b. The second oil passage b is equipped with a second solenoid valve 11 and a third solenoid valve 12. The first oil passage a and the second oil passage b are interconnected.

[0039] In this embodiment, when motor 1 and the first solenoid valve 9 are simultaneously energized, motor 1 drives gear pump 2 to pump the oil in hydraulic tank 4 to the actuator connected to the first port 31. Similarly, when motor 1 and the second solenoid valve 11 are simultaneously energized, the actuator connected to the second port 32 operates. When the motor is de-energized and the first solenoid valve 9 and the third solenoid valve 12 are energized, the oil in the actuator at the first port 31 flows back to hydraulic tank 4 through throttle valve 14. The main function of throttle valve 14 is to prevent the oil from flowing back too quickly, which could cause the actuator to move too much and create a hazard. Similarly, when motor 1 is de-energized and the second solenoid valve 11 and the third solenoid valve 12 are simultaneously energized, the oil in the actuator at the second port 32 flows back to hydraulic tank 4 through throttle valve 14, thus achieving internal circulation of the oil within the entire electro-hydraulic control system.

[0040] Among them, the one-way valve 10 ensures that the oil does not flow back to the oil pump and thus damage the oil pump's sealing performance.

[0041] Preferably, the first oil circuit a is also equipped with an oil inlet filter 16 to facilitate the filtration of hydraulic oil and the removal of impurities.

[0042] Specifically, the first solenoid valve 9 on the first oil circuit a and the second solenoid valve 11 and the third solenoid valve 12 on the second oil circuit b are both two-position two-way solenoid valves.

[0043] Specifically, one of the first solenoid valve 9 and the second solenoid valve 11 is a bidirectional shut-off solenoid valve.

[0044] In one embodiment, the first oil circuit a branches into an overflow circuit c connected to the hydraulic oil tank 4, and the overflow circuit c is equipped with an overflow valve 13. In this embodiment, the overflow valve 13 ensures that the system pressure is not too high, thus protecting the hydraulic components from damage and preventing the motor from being overloaded.

[0045] In one embodiment, a throttle valve 14 is provided on the second oil passage b. This configuration in this embodiment prevents the oil backflow rate from being too fast, thus preventing the actuator from operating too aggressively and causing a hazard.

[0046] In one embodiment, please refer to Figure 3A 2kΩ 20W pre-charging resistor is connected in parallel to the main contacts of contactor 8. In this embodiment, the controller 6 of motor 1 contains a large-capacity capacitor. Directly energizing the capacitor is equivalent to a short circuit, generating a huge current that could damage the controller. The vehicle's power battery provides 110V DC power, which is supplied to controller 6 via contactor 8. A 2kΩ 20W pre-charging resistor is connected in parallel to the main contacts of high-voltage contactor 8. After the vehicle's power supply is turned on, the capacitor inside controller 6 is first charged through the pre-charging resistor with a charging current of approximately 55mA, causing the voltage at controller 6 to rise slowly. When controller 6 detects that the input voltage is close to the power supply voltage, it outputs a signal to connect contactor 8, simultaneously short-circuiting the pre-charging resistor circuit to deactivate it. The pre-charging resistor ensures that the high-voltage contactor only connects when the input and output voltages are close, avoiding the large current generated at the moment of direct connection that could damage the internal components of the controller. It also prevents arcing caused by the large current at the moment of closing, thus extending the service life of the high-voltage contactor.

[0047] In one embodiment, a 1N5408 (1000V 3A) freewheeling diode is connected in parallel with the coil of contactor 8, with the diode's positive and negative terminals reversed to the opposite of the control power supply. In this embodiment, the control power supply for contactor 8 is the 110V DC power supplied by the vehicle. When the coil is energized, the diode circuit is not conductive; when the coil switches from energized to de-energized, according to the law of electromagnetic induction, a back electromotive force (EMF) of more than twice the normal value is generated in the coil. At this time, the diode and the coil form a circuit, consuming the back EMF and preventing it from interfering with or even damaging the vehicle's electrical system.

[0048] In one embodiment, please refer to Figure 4 It also includes a remote control receiver 15 for remotely controlling the operation of the electro-hydraulic system. Understandably, the remote control receiver 15 is equipped with a transmitter, which has buttons for different control functions. When the transmitter start button is pressed, the remote control receiver 15 starts. Then, pressing the first button closes switches S1 and S4, energizing coil KM1. Figure 2 Contactors and Figure 3 The first solenoid valve 9 operates simultaneously, and the hydraulic component connected to the first oil port 31 performs an action; pressing the second button closes S2 and S4, energizing coil KM2. Figure 2 Contactor 8 and Figure 3 The second solenoid valve 11 operates simultaneously, and the hydraulic components connected to the second oil port 32 perform actions; when the third button is pressed, S1 and S3 close, the coils of KM1 and KM3 are energized, and the oil in the first oil port 31 returns to the hydraulic oil tank 4; when the third button is pressed, S2 and S3 close, the coils of KM2 and KM3 are energized, and the oil in the second oil port 32 returns to the hydraulic oil tank 4; when the stop button is pressed, the entire system loses power and stops operating.

[0049] In one embodiment, motor 1 is an AC asynchronous motor. Specifically, it is an AC80V 3.0kW AC asynchronous motor.

[0050] It should be noted that if the embodiments of this utility model involve directional indicators such as up, down, left, right, front, back, etc., the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture as shown in the attached figure. If the specific posture changes, the directional indicators will also change accordingly.

[0051] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied. Furthermore, "multiple" refers to two or more. Moreover, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent.

[0052] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery, characterized in that... ,include: A power unit is used to convert mechanical energy into hydraulic energy. The power unit includes a motor (1), which is connected to a gear pump (2) via a coupling. A central valve block (3) is provided between the gear pump (2) and the motor (1). The central valve block (3) is provided with a first oil port (31) and a second oil port (32). The gear pump (2) is located in a hydraulic oil tank (4). A hydraulic control unit is used to control and change the hydraulic oil circuit. The hydraulic control unit is located on the central valve block (3), and the hydraulic control unit includes a hydraulic control valve group (5), which includes multiple solenoid valves. The electrical control unit is used to convert the 110V high-voltage DC power output by the power supply into the 80V AC power required by the AC motor. It includes a controller (6), which is electrically connected to a solid-state relay (7) and a contactor (8). The solid-state relay (7) and the contactor (8) control the on / off state of the control circuit and the main power supply circuit, respectively.

2. The electric hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 1, characterized in that: The first oil port (31) is connected to the hydraulic oil tank (4) through the first oil passage (a). The first oil passage (a) is equipped with a first solenoid valve (9) and a check valve (10). The second oil port (32) is connected to the hydraulic oil tank (4) through the second oil passage (b). The second oil passage (b) is equipped with a second solenoid valve (11) and a third solenoid valve (12). The first oil passage (a) and the second oil passage (b) are interconnected.

3. The electric hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 2, characterized in that: The first solenoid valve (9) on the first oil circuit (a) and the second solenoid valve (11) and the third solenoid valve (12) on the second oil circuit (b) are both two-position two-way solenoid valves.

4. The electric hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 2, characterized in that: One of the first solenoid valve (9) and the second solenoid valve (11) is a bidirectional shut-off solenoid valve.

5. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 2, characterized in that: The first oil circuit (a) has a branch to an overflow circuit (c) that is connected to the hydraulic oil tank (4), and the overflow circuit (c) is equipped with an overflow valve (13).

6. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 2, characterized in that: A throttle valve (14) is provided on the second oil circuit (b).

7. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 1, characterized in that: The main contacts of the contactor (8) are connected in parallel with a 2 kΩ 20W pre-charge resistor.

8. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 1, characterized in that: The coil of the contactor (8) is connected in parallel with a 1N5408 freewheeling diode, the positive and negative terminals of which are opposite to those of the control power supply.

9. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 1, characterized in that: It also includes a remote receiver (15) for remotely controlling the operation of the electro-hydraulic system.

10. An electric-hydraulic system that can be directly equipped with a new energy high-voltage battery as described in claim 1, characterized in that: The motor (1) is an AC asynchronous motor.

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