CN114583765A

CN114583765A - Energy control system and method and aerial work equipment

Info

Publication number: CN114583765A
Application number: CN202210217536.3A
Authority: CN
Inventors: 朱后; 王光辉; 熊路; 沈裕强; 吴俊锋
Original assignee: Hunan Zoomlion Intelligent Aerial Work Machinery Co Ltd
Current assignee: Hunan Zoomlion Intelligent Aerial Work Machinery Co Ltd
Priority date: 2022-03-07
Filing date: 2022-03-07
Publication date: 2022-06-03

Abstract

The invention relates to the technical field of engineering machinery, and discloses an energy control system and method and aerial work equipment. The energy control system includes: target rotation speed obtaining means for obtaining a target rotation speed of the motor; actual rotation speed obtaining means for obtaining an actual rotation speed of the motor; and the control device is used for controlling the fuel injection quantity of the engine and the output torque of the motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor so as to maintain the actual rotating speed of the motor within a preset range, wherein the engine is coaxially coupled with the motor. The invention adopts a cooperative control strategy to realize the automatic distribution of the torque of the power system without estimating the required power and the power discharge power.

Description

Energy control system and method and aerial work equipment

Technical Field

The invention relates to the technical field of engineering machinery, in particular to an energy control system, an energy control method and high-altitude operation equipment.

Background

The hybrid aerial work platform has the advantages of both a diesel power platform and a pure electric aerial work platform: the performance on rugged terrain can be equal to diesel power, and the requirements of quiet and low emission of indoor environment can be met. Because the hybrid aerial work platform has better working condition adaptability and wider application, the aerial work platform is likely to have higher utilization ratio for renters. Therefore, the research on the hybrid power aerial working vehicle has important significance.

The energy management technology is a key technology of hybrid power and is developed relatively mature in the field of automobiles. However, the structure and working conditions of the aerial work platform are greatly different from those of an automobile, so that the energy management technology in the field of automobiles is difficult to be applied to the aerial work platform. For example, in the automotive field, accurate estimation of the power demand (i.e., power command) and the power each power source can provide (e.g., the power a battery can provide at different states of charge) is often required to achieve energy control. However, the aerial platform cannot accurately estimate its required power due to the following three main conditions: on the first hand, the hydraulic drive is adopted, and the hydraulic drive comprises a walking system and a boarding system, wherein the arm support structure of the boarding system is complex, the operation postures are more, and the action combinations are more; in the second aspect, an intermittent working system and a short-time working system are adopted, and the fluctuation range of the required power is large; in a third aspect, lead-acid batteries are still mainly used at present, SOC estimation of lead-acid batteries is very inaccurate, and estimation of dischargeable power of current batteries is difficult. Therefore, the energy control technology in the automotive field cannot be adapted to aerial work platforms.

Disclosure of Invention

The invention aims to provide an energy control system, an energy control method and high-altitude operation equipment, which adopt a cooperative control strategy to realize automatic distribution of power system torque without estimating required power and power supply discharge power.

To achieve the above object, a first aspect of the present invention provides an energy control system comprising: target rotation speed obtaining means for obtaining a target rotation speed of the motor; actual rotation speed obtaining means for obtaining an actual rotation speed of the motor; and the control device is used for controlling the fuel injection quantity of the engine and the output torque of the motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor so as to maintain the actual rotating speed of the motor within a preset range, wherein the engine is coaxially coupled with the motor.

Preferably, the target rotation speed obtaining means includes: the first target rotating speed acquisition module is used for acquiring the target rotating speed of the engine; and a second target rotation speed acquisition module for determining a target rotation speed of the engine as a target rotation speed of the motor.

Preferably, the control device includes: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: controlling the fuel injection amount of the engine to be reduced under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor; or controlling the fuel injection amount of the engine to increase under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor, and a second controller for controlling the output torque of the motor to change as follows by adopting the cooperative control strategy: controlling the output torque of the motor to be a negative value and to be reduced in the case where the actual rotation speed of the motor is greater than the target rotation speed of the motor; or controlling the output torque of the motor to be a positive value and to be increased when the actual rotation speed of the motor is less than the target rotation speed of the motor.

Preferably, the control device includes: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: under the condition that the actual rotating speed of the motor is larger than the target rotating speed of the motor, and the difference value between the actual rotating speed and the target rotating speed of the motor is increased, controlling the fuel injection quantity of the engine to be reduced at a first acceleration; or in the case that the actual rotating speed of the electric motor is greater than the target rotating speed of the electric motor and the difference value between the actual rotating speed and the target rotating speed of the electric motor is reduced, controlling the fuel injection quantity of the engine to be reduced at a second acceleration, and controlling the output torque of the electric motor to be changed by adopting the cooperative control strategy, wherein the controller is used for controlling the following steps: controlling the output torque of the motor to be a negative value and to be reduced at a fifth speed under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is increased, wherein the ratio of the first acceleration to the fifth speed is smaller than a preset ratio; or under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is reduced, controlling the output torque of the motor to be a negative value and to be reduced by sixth acceleration, wherein the ratio of the second acceleration to the sixth acceleration is greater than the ratio of the first acceleration to the fifth acceleration and is smaller than the preset ratio.

Preferably, the control device includes: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: controlling the fuel injection amount of the engine to increase at a third acceleration under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased; or in the case that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is reduced, controlling the fuel injection quantity of the engine to be increased at a fourth acceleration, and controlling the output torque of the motor to be changed in the following way by adopting the cooperative control strategy: controlling the output torque of the motor to be a positive value and to increase at a seventh acceleration under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased, wherein the ratio of the third acceleration to the seventh acceleration is greater than a preset ratio; or under the condition that the actual rotating speed of the motor is smaller than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is reduced, controlling the output torque of the motor to be a positive value and to be increased by an eighth acceleration, wherein the ratio of the eighth acceleration to the fourth acceleration is larger than the preset ratio and smaller than the ratio of the third acceleration to the seventh acceleration.

Preferably, the second controller is configured to control the output torque of the motor to be a negative value and the reducing includes: controlling an output torque reduction of the electric motor using a charging power control strategy.

Preferably, the second controller for controlling the output torque reduction of the electric motor using a charging power control strategy comprises: controlling an output torque of the motor to be reduced to pre-charge the power supply with a first charging current in a case where a voltage of the power supply is greater than a first voltage and less than a second voltage, wherein the second voltage is less than a charge cutoff voltage of the power supply; under the condition that the voltage of the power supply is greater than the second voltage and less than a third voltage, controlling the output torque of the motor to be reduced so as to perform constant-current charging on the power supply by adopting a second charging current, wherein the second charging current is greater than the first charging current; or controlling the output torque of the motor to be reduced according to the current of the power supply in the case where the voltage of the power supply is greater than or equal to the third voltage.

Preferably, the second controller for controlling the output torque of the motor to be reduced according to the current of the power source includes: controlling an output torque of the motor to be reduced to perform constant-voltage charging of the power supply with a third voltage in a case where a voltage of the power supply is greater than or equal to the third voltage and a charging current of the power supply is greater than a third charging current, wherein the third charging current is less than the first charging current; or controlling the output torque of the motor to be reduced to stop charging the power supply when the voltage of the power supply is greater than or equal to the third voltage and the charging current of the power supply is less than or equal to the third charging current.

Through the technical scheme, the fuel injection quantity of the engine and the output torque of the motor are controlled by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor creatively, so that the actual rotating speed of the motor is maintained within a preset range. Thus, the present invention employs a coordinated control strategy to achieve automatic distribution of powertrain torque without requiring estimation of demand power and power supply discharge power.

A second aspect of the present invention provides an energy control method, including: acquiring a target rotating speed of the motor; acquiring the actual rotating speed of the motor; and controlling the fuel injection quantity of an engine and the output torque of the motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor so as to maintain the actual rotating speed of the motor within a preset range, wherein the engine is coaxially coupled with the motor.

For details and advantages of the energy control method provided by the embodiment of the present invention, reference may be made to the above description of the energy control system, and further description is omitted here.

A third aspect of the present invention provides aerial work apparatus comprising: the energy control system.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a block diagram of an energy control system provided in accordance with an embodiment of the present invention;

FIG. 2 is a block diagram of an energy control system provided in accordance with an embodiment of the present invention;

FIG. 3 is a flowchart illustrating a control based on a target differential rotational speed, according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a cooperative control strategy provided by an embodiment of the present invention; and

fig. 5 is a flowchart for controlling the output torque reduction of the motor according to an embodiment of the present invention.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

Before describing in detail various embodiments of the present invention, a brief description of the output torque of the motor will be provided.

The output torque of the motor is a vector, and when the output torque is a positive value, the output torque can indicate that the motor is in a discharging state or a motor state; when it is a negative value, it may indicate that the motor is in a power generation state, and the output torque of the motor at this time may also be referred to as a power generation torque (the power generation torque of the motor is a scalar quantity having a magnitude equal to that of the output torque of the motor).

Fig. 1 is a diagram of an energy control system according to an embodiment of the present invention. As shown in fig. 1, the energy control system may include: target rotation speed obtaining means 10 for obtaining a target rotation speed of the motor; actual rotational speed obtaining means 20 for obtaining an actual rotational speed of the motor; and a control device 30, configured to control an oil injection amount of the engine and an output torque of the electric motor by using a cooperative control strategy according to the target rotation speed and the actual rotation speed of the electric motor, so as to maintain the actual rotation speed of the electric motor within a preset range.

Wherein the engine is coaxially coupled with the motor. Thereby, the actual rotational speed of the engine and the actual rotational speed of the electric motor are kept the same.

The following will describe the acquisition of the target rotation speed of the electric motor from the target rotation speed of the engine.

The vehicle control unit 1 shown in fig. 2 collects an operation signal of the aerial work equipment, and controls the target rotational speed of the engine according to the content of the operation signal. Specifically, the target rotational speed of the engine is related to the content of the operation signal (for example, it is related to the action type of the operation signal, but it is not related to the action speed of the operation signal).

In the first type of embodiment, the target rotation speed of the electric motor may be the same as the target rotation speed of the engine. Specifically, the target rotational speed acquisition means 20 may include: the first target rotating speed acquisition module is used for acquiring a target rotating speed of the engine; and a second target rotation speed acquisition module for determining a target rotation speed of the engine as a target rotation speed of the motor.

For example, if it is determined from the above that the target rotation speed of the engine is 2000rpm, the target rotation speed of the electric motor may also be 2000 rpm.

Wherein the preset range may be [ -n [)_m-sv-n₁，n_m-sv+n₂]Wherein n is_m-svIs the target speed of the motor; n is₁、n₂The positive values are preset for two respectively, and can be reasonably set according to actual conditions.

The following describes a process in which the control device 30 controls the engine and the motor using a cooperative control strategy. The first controller can control the rotating speed of the engine by controlling the fuel injection quantity of the engine; the second controller may control the rotational speed of the motor through the torque loop.

In one embodiment, the control device 30 includes: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: controlling the fuel injection quantity of the engine to be reduced under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor; or controlling the fuel injection amount of the engine to increase under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor, and a second controller for controlling the output torque of the motor to change as follows by adopting the cooperative control strategy: controlling the output torque of the motor to be a negative value and to be reduced in the case where the actual rotation speed of the motor is greater than the target rotation speed of the motor; or controlling the output torque of the motor to be a positive value and to be increased when the actual rotation speed of the motor is less than the target rotation speed of the motor.

For details of the specific control procedures of the first controller and the second controller, the target rotation speed of the engine is the same as the target rotation speed of the electric motor in another type of embodiments described below, and details thereof are not repeated herein.

More specifically, in one embodiment, the control device 30 may include: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: controlling the fuel injection quantity of the engine to be reduced at a first acceleration under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is increased; or in the case that the actual rotating speed of the electric motor is greater than the target rotating speed of the electric motor and the difference value between the actual rotating speed and the target rotating speed of the electric motor is reduced, controlling the fuel injection quantity of the engine to be reduced at a second acceleration, and controlling the output torque of the electric motor to be changed by adopting the cooperative control strategy, wherein the controller is used for controlling the following steps: controlling the output torque of the motor to be a negative value and to be reduced at a fifth speed under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is increased, wherein the ratio of the first acceleration to the fifth speed is smaller than a preset ratio; or under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is reduced, controlling the output torque of the motor to be a negative value and to be reduced by sixth acceleration, wherein the ratio of the second acceleration to the sixth acceleration is greater than the ratio of the first acceleration to the fifth acceleration and is smaller than the preset ratio.

In another embodiment, the control device 30 may include: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: under the condition that the actual rotating speed of the motor is smaller than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased, controlling the fuel injection quantity of the engine to be increased at a third acceleration; or in the case that the actual rotating speed of the electric motor is less than the target rotating speed of the electric motor and the difference value between the target rotating speed and the actual rotating speed of the electric motor is reduced, controlling the fuel injection quantity of the engine to be increased at a fourth acceleration, and a second controller for controlling the output torque of the electric motor to be changed by adopting the cooperative control strategy: under the condition that the actual rotating speed of the motor is smaller than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased, controlling the output torque of the motor to be a positive value and to be increased by a seventh acceleration, wherein the ratio of the third acceleration to the seventh acceleration is larger than a preset ratio; or under the condition that the actual rotating speed of the motor is smaller than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is reduced, controlling the output torque of the motor to be a positive value and to be increased by an eighth acceleration, wherein the ratio of the eighth acceleration to the fourth acceleration is larger than the preset ratio and smaller than the ratio of the third acceleration to the seventh acceleration.

For more specific control procedures of the first controller and the second controller, details of a target rotation speed of the engine and a target rotation speed of the electric motor in another type of embodiment described below can be found, and detailed description thereof is omitted here.

However, if the target rotation speed of the electric motor is equal to the target rotation speed of the engine, in the case that the voltage of the power supply is less than the charge cut-off voltage of the power supply, there may be a case that the charging power is insufficient for some charging conditions, and therefore, in the above embodiment, a corresponding charging device needs to be provided to supplement the insufficient charging power. In order to further control the engine as the main power source and better adapt to various charging conditions, in a second class of embodiments, the target speed of the electric motor may be determined based on a control strategy of the target speed difference. In the second class of embodiments, the target rotational speed obtaining device 10 may include: the voltage acquisition module is used for acquiring the voltage of the power supply; the first target rotating speed acquisition module is used for acquiring a target rotating speed of the engine; and the second target rotating speed acquisition module is used for determining the target rotating speed of the motor according to the voltage of the power supply, the charging cut-off voltage of the power supply, the target rotating speed of the engine and a preset rotating speed difference value.

Wherein the second target rotation speed obtaining module for determining the target rotation speed of the motor may include: determining a difference between a target rotation speed of the engine and the preset rotation speed as a target rotation speed of the motor in a case where the voltage of the power supply is less than a charge cut-off voltage of the power supply; or determining the target rotation speed of the engine as the target rotation speed of the motor in a case where the voltage of the power supply is greater than or equal to a charge cutoff voltage of the power supply.

Specifically, as shown in FIG. 3, the process of determining the target rotational speed of the motor may include steps S301-S303. Wherein the target speed n of the engine_e-svMay be determined based on operating signals of the aerial work equipment.

Step S301, judging U<U_coIf yes, go to step S302; otherwise, step S303 is executed.

Wherein U is the voltage of the power supply, U_coThe charge cutoff voltage of the power supply.

Step S302, determining a target rotating speed n of the motor_m-sv＝n_e-sv-n_diff。

If true (i.e., yes), indicating that the power supply can be charged to maintain a high state of charge of the power supply, then n is followed_m-sv＝n_e-sv-n_diff(n_diffFor a predetermined speed difference, for example 50rpm, which can be set reasonably to a fixed value according to actual needs) determining the target speed n of the motor_m-sv. In this case, when the actual rotation speed of the engine is greater than its target rotation speed (i.e., the load is reduced), the actual rotation speed of the engine is lower than the target rotation speed of the engine due to the electric motor and the engineThe actual rotational speeds are the same, so that the actual rotational speed of the electric motor is greater than the target rotational speed n thereof_m-svThe motor works in a power generation state, and the engine is the only power source at the moment, so that energy is provided for the whole vehicle to act, and redundant mechanical energy is converted into electric energy through the motor to be stored in the power battery. When the actual rotation speed of the engine fluctuates at n_e-svAnd n_m-svIn between (i.e., the load increases, the energy provided by the engine is sufficient), the motor will not need to power the system (the output torque may be negative or 0 depending on whether the power supply is fully charged), since the actual speed of the motor is greater than its target speed, but only the engine; when the actual speed of the engine is less than n_m-svIn the middle (namely, the load is increased, and the energy provided by the engine is insufficient), the engine is used for providing main power, the motor is used for providing insufficient energy, and the auxiliary engine is used for providing energy for the whole vehicle, so that the characteristic that the engine is used as a main power source is further strengthened.

The preset range (at which the actual rotational speed of the motor is maintained) for this situation may be [ -n ]_m-sv-n₁，n_e-sv+n₂]Wherein n is_m-svIs the target speed of the motor; n is_e-svIs the target rotation speed of the generator; n is₁、n₂The positive values are preset for two respectively, and can be reasonably set according to actual conditions.

Step S303, determining the target rotating speed n of the motor_m-sv＝n_e-sv。

If not (i.e. NO), indicating that there is no need to charge the power supply, which is in a high state of charge, then according to n_m-sv＝n_e-svDetermining a target speed n of an electric motor_m-sv。

The preset range (at which the actual rotational speed of the motor is maintained) for this situation may be [ -n ]_m-sv-n₁，n_m-sv+n₂]Wherein n is_m-svIs the target speed of the motor; n is₁、n₂The positive values are preset for two respectively, and can be reasonably set according to actual conditions.

The present embodiment achieves automatic distribution of powertrain torque by setting different target speeds for the engine and the motor and employing a coordinated control strategy without requiring estimation of the power demand and the power source discharge. The control strategy of the target rotating speed difference is adopted, the output torque of the engine is fully utilized, the motor absorbs redundant energy of the engine in time, and the motor serves as auxiliary power to provide energy when the torque of the engine is insufficient.

First, the case where the target rotation speed of the engine is the same as the target rotation speed of the motor is analyzed.

In an embodiment, in the case where the target rotation speed of the engine is determined as the target rotation speed of the electric motor, the control device 30 may include: a first controller configured to control an amount of fuel injected by the engine to be reduced in a case where an actual rotation speed of the electric motor is greater than a target rotation speed of the electric motor; and a second controller for controlling the output torque of the motor to be negative and to be reduced in a case where the actual rotation speed of the motor is greater than the target rotation speed of the motor.

That is, when the load becomes smaller, the actual rotation speed of the motor/engine is greater than its target rotation speed, and the fuel injection amount is controlled to be reduced by the first controller (the engine controller 2 shown in fig. 2) to prevent the actual rotation speed of the engine from rising; at the same time, the output torque of the motor (which is a negative value, i.e., the power generation torque is provided) is controlled to be reduced by the second controller (the motor controller 3 shown in fig. 2). Thus, the two controllers can control the rotation speed of the engine (or the motor) not to change along with the change of the load, namely, the constant speed control is realized.

In an embodiment, in the case where the target rotation speed of the engine is determined as the target rotation speed of the electric motor, the control device 30 may include: a first controller configured to control an amount of fuel injected by the engine to increase in a case where an actual rotation speed of the electric motor is less than a target rotation speed of the electric motor; and a second controller for controlling the output torque of the motor to be a positive value and to be increased, when the actual rotation speed of the motor is less than the target rotation speed of the motor.

That is, when the load becomes large, the actual rotational speed of the motor/engine is smaller than its target rotational speed, and the increase of the fuel injection amount is controlled by the first controller (the engine controller 2 shown in fig. 2) to prevent the engine from stalling; at the same time, the controller increases the output torque of the motor (which is a positive value, that is, the motor is in an electric state) by the second controller (such as the motor controller 3 shown in fig. 2). Thus, the two controllers can control the rotation speed of the engine (or the motor) not to change along with the change of the load, namely, the constant speed control is realized.

More specifically, in the case where the target rotation speed of the engine is determined as the target rotation speed of the electric motor, the control device 30 includes: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: under the condition that the actual rotating speed of the motor is larger than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is increased, controlling the fuel injection quantity of the engine to be reduced at a first acceleration; controlling the fuel injection quantity of the engine to be reduced at a second acceleration under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is reduced; controlling the fuel injection amount of the engine to increase at a third acceleration under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased; or in the case that the actual rotating speed of the electric motor is less than the target rotating speed of the electric motor and the difference value between the target rotating speed and the actual rotating speed of the electric motor is reduced, controlling the fuel injection quantity of the engine to be increased at a fourth acceleration, and a second controller for controlling the output torque of the electric motor to be changed by adopting the cooperative control strategy: under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is gradually increased, controlling the output torque of the motor to be a negative value and to be reduced at a fifth speed, wherein the ratio of the first acceleration to the fifth speed is smaller than a preset ratio; under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed of the motor and the target rotating speed is gradually reduced, controlling the output torque of the motor to be a negative value and to be reduced by a sixth acceleration, wherein the ratio of the second acceleration to the sixth acceleration is greater than the ratio of the first acceleration to the fifth acceleration and is smaller than the preset ratio; or under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased, controlling the output torque of the motor to be a positive value and to be increased by a seventh acceleration, wherein the ratio of the third acceleration to the seventh acceleration is greater than the preset ratio; or under the condition that the actual rotating speed of the motor is smaller than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is reduced, controlling the output torque of the motor to be a positive value and to be increased by an eighth acceleration, wherein the ratio of the eighth acceleration to the fourth acceleration is larger than the preset ratio and smaller than the ratio of the third acceleration to the seventh acceleration.

Wherein the preset ratio may be a ratio of a maximum torque of the motor to a maximum torque of the engine (e.g., K0).

First, in the case where the actual rotation speed of the motor/generator is greater than the target rotation speed thereof, it can be divided into two cases where the difference between the actual rotation speed and the target rotation speed is increased and decreased as shown in fig. 4. Here, a specific control process of the control device 30 described above will be described with reference to fig. 4.

In one embodiment, as shown in the first part of fig. 4, in the case where the actual rotation speed of the electric motor is greater than the target rotation speed of the electric motor and the difference between the actual rotation speed and the target rotation speed of the electric motor increases, the amount of fuel injected by the engine is controlled by the first controller (e.g., the engine controller 2 shown in fig. 2) to decrease at a first acceleration (i.e., slowly decrease), and at the same time, the output torque of the electric motor is controlled by the second controller (e.g., the motor controller 3 shown in fig. 2) to be negative and to decrease at a fifth speed (i.e., rapidly decrease) (which may also be expressed as controlling the electric generation torque of the electric motor to increase at a fifth speed). Wherein a ratio of the first acceleration to the fifth acceleration is less than a preset ratio.

That is, when the load is decreased so that the actual rotation speed of the motor/engine is greater than its target rotation speed and the difference gradually increases, the motor controller 3 responds faster than the engine controller 2 so that the ratio K1 of the acceleration at which the fuel injection amount of the engine is decreased to the acceleration at which the output torque of the motor is decreased (i.e., the acceleration at which the power generation torque is increased) is smaller (e.g., much smaller) than K0, whereby the electric motor 5 contributes much to the decrease in the output torque (i.e., the electric motor is in the power generation state) while mainly using the fuel injection amount of the engine as the main power source.

In one embodiment, as shown in the second part of fig. 4, in the case where the actual rotational speed of the electric motor is greater than the target rotational speed of the electric motor and the difference between the actual rotational speed of the electric motor and the target rotational speed is decreased, the fuel injection amount of the engine is controlled by the first controller (e.g., the engine controller 2 shown in fig. 2) to be decreased at the second acceleration (i.e., slowly decreased), and at the same time, the output torque of the electric motor is controlled by the second controller (e.g., the motor controller 3 shown in fig. 2) to be a negative value and to be decreased at the sixth acceleration (i.e., rapidly decreased) (which may also be expressed as controlling the power generation torque of the electric motor to be increased at the sixth acceleration). Wherein a ratio of the second acceleration to the sixth acceleration is greater than a ratio of the first acceleration to the fifth acceleration and (a ratio of the second acceleration to the sixth acceleration) is less than the preset ratio.

That is, when the load is decreased so that the actual rotation speed of the motor/engine is greater than its target rotation speed and the difference gradually decreases, the motor controller 3 responds faster than the engine controller 2 (but slower than the response of the embodiment corresponding to the first part of fig. 4 so that the ratio K2 of the acceleration at which the fuel injection amount of the engine decreases to the acceleration at which the output torque of the motor decreases (i.e., the acceleration at which the power generation torque increases) is smaller than K0 and K2 is greater than K1, whereby the electric motor 5 contributes more to the decrease in the output torque (i.e., the electric motor is in the power generation state) while mainly using the fuel injection amount of the engine as the main power source.

Second, for the case where the actual rotational speed of the motor/generator is less than the target rotational speed thereof, it can be divided into two cases where the difference between the target rotational speed and the actual rotational speed is increased and decreased as shown in fig. 4. Here, a specific control process of the control device 30 described above will be described with reference to fig. 4.

In one embodiment, as shown in the third part of fig. 4, in the case where the actual rotation speed of the electric motor is less than the target rotation speed of the electric motor and the difference between the target rotation speed and the actual rotation speed of the electric motor increases, the fuel injection amount of the engine is controlled by the first controller (e.g., the engine controller 2 shown in fig. 2) to increase at the third acceleration, and at the same time, the output torque of the electric motor is controlled by the second controller (e.g., the motor controller 3 shown in fig. 2) to be a positive value and to increase at the seventh acceleration. Wherein a ratio of the third acceleration to the seventh acceleration is greater than the preset ratio.

That is, when the load is increased so that the actual rotation speed of the motor/engine is less than its target rotation speed and the difference gradually increases, the engine controller 2 responds faster than the motor controller 3 so that the ratio K3 of the acceleration of the increase in the fuel injection quantity of the engine to the acceleration of the increase in the output torque of the motor is greater (e.g., much greater) than K0, whereby the engine contributes much to the increase in the output torque, that is, the fuel injection quantity of the engine is mainly used as the main power source; while the motor responds at a slower speed, increasing the output torque, which is energized as auxiliary power, i.e. the motor is in the motoring state.

In one embodiment, as shown in the fourth part of fig. 4, in the case where the actual rotation speed of the electric motor is less than the target rotation speed of the electric motor and the difference between the target rotation speed and the actual rotation speed of the electric motor is decreased, the fuel injection amount of the engine is controlled to increase at the fourth speed by the first controller (e.g., engine controller 2 shown in fig. 2), and at the same time, the output torque of the electric motor is controlled to be a positive value and to increase at the eighth speed by the second controller (e.g., motor controller 3 shown in fig. 2). Wherein a ratio of the eighth acceleration to the fourth acceleration is greater than the preset ratio and less than a ratio of the third acceleration to the seventh acceleration

That is, when the load is increased so that the actual rotation speed of the motor/engine is less than its target rotation speed and the difference gradually decreases, the engine controller 2 responds faster than the motor controller 3 (but slower than the response of the embodiment corresponding to the third portion in fig. 4) so that the ratio K4 of the acceleration at which the amount of fuel injected by the engine increases to the acceleration at which the output torque of the motor increases is greater than K0 and K4 is less than K3, whereby the engine contributes more to the increased output torque, i.e., the amount of fuel injected by the engine is mainly the main power source; while the motor responds at a relatively slow speed, increasing the output torque, which is energized as auxiliary power, i.e. the motor is in the motoring state.

Next, a case where there is a difference between the target rotation speed of the engine and the target rotation speed of the motor is analyzed. For example, the target rotational speed of the generator is 2000 rpm; the target speed of the motor was 1950 rpm.

In an embodiment, in the case where the difference between the target rotation speed of the engine and the preset rotation speed difference is determined as the target rotation speed of the electric motor, the control device 30 may include: a first controller configured to control an amount of fuel injected by the engine to be reduced in a case where an actual rotation speed of the electric motor is greater than a target rotation speed of the engine; and a second controller for controlling the output torque of the electric motor to be a negative value and to be reduced in a case where the actual rotation speed of the electric motor is greater than the target rotation speed of the engine.

That is, when the load becomes small, the actual rotation speed of the engine is greater than its target rotation speed (for example, 2000rpm), and the fuel injection amount is controlled to be reduced by the first controller (the engine controller 2 shown in fig. 2) to prevent the actual rotation speed of the engine from rising; at the same time, the output torque of the motor (which is a negative value, i.e., the power generation torque is provided) is controlled to be reduced by the second controller (the motor controller 3 shown in fig. 2). Thus, the two controllers can control the rotation speed of the engine (or the motor) not to change along with the change of the load, namely, the constant speed control is realized.

In an embodiment, in the case where the target rotation speed of the engine is determined as the target rotation speed of the electric motor, the control device 30 may include: a first controller configured to control an amount of fuel injected by the engine to increase in a case where an actual rotation speed of the electric motor is less than a target rotation speed of the engine; and a second controller for controlling an output torque of the electric motor to a non-positive value in a case where an actual rotation speed of the electric motor is greater than a target rotation speed of the electric motor and less than a target rotation speed of the engine; or controlling the output torque of the electric motor to be a positive value and to be increased when the actual rotation speed of the electric motor is less than the target rotation speed of the engine.

That is, when the load becomes large, if the actual rotation speed of the motor is greater than the target rotation speed thereof (e.g., 1950rpm) and less than the target rotation speed of the engine (e.g., 2000rpm), the fuel injection amount is controlled to be increased by the first controller (e.g., the engine controller 2 shown in fig. 2) to prevent the engine from stalling; meanwhile, the controller controls the motor to not supply power to the system (the output torque is controlled to be a negative value or 0 according to whether the power supply is fully charged) through a second controller (such as the motor controller 3 shown in fig. 2). When the load becomes larger, if the actual rotation speed of the motor is smaller than the target rotation speed (for example, 1950rpm), controlling the fuel injection quantity to be increased through a first controller (such as an engine controller 2 shown in fig. 2) to prevent the engine from stalling; at the same time, the controller increases the output torque of the motor (which is a positive value, that is, the motor is in an electric state) by the second controller (such as the motor controller 3 shown in fig. 2). Therefore, the rotation speed of the engine (or the motor) can be controlled by the two controllers without changing along with the change of the load, namely, the constant speed control is realized.

More specifically, in the case where the difference between the target rotation speed of the engine and the preset rotation speed difference is determined as the target rotation speed of the electric motor, the control device 30 may include: the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy: controlling the fuel injection amount of the engine to decrease at a ninth acceleration in a case where the actual rotation speed of the electric motor is greater than the target rotation speed of the engine and the difference between the actual rotation speed of the electric motor and the target rotation speed of the engine increases; controlling the fuel injection amount of the engine to decrease at a tenth acceleration in the case where the actual rotation speed of the electric motor is greater than the target rotation speed of the electric motor and the difference between the actual rotation speed of the electric motor and the target rotation speed of the engine decreases; controlling the fuel injection amount of the engine to increase at an eleventh acceleration in a case where the actual rotation speed of the electric motor is less than the target rotation speed of the engine and the difference between the target rotation speed of the engine and the actual rotation speed of the electric motor increases; or in the case that the actual rotation speed of the electric motor is less than the target rotation speed of the engine and the difference between the target rotation speed of the engine and the actual rotation speed of the electric motor is reduced, controlling the fuel injection amount of the engine to be increased at a twelfth acceleration, and a second controller for controlling the output torque of the electric motor to be changed by adopting the cooperative control strategy: controlling the output torque of the electric motor to be a negative value and to decrease at a thirteenth acceleration in a case where the actual rotation speed of the electric motor is greater than the target rotation speed of the engine and the difference between the actual rotation speed of the electric motor and the target rotation speed of the engine increases, wherein a ratio of the ninth acceleration to the thirteenth acceleration is smaller than a preset ratio; controlling the output torque of the electric motor to be a negative value and to decrease at a fourteenth acceleration in a case where the actual rotational speed of the electric motor is greater than the target rotational speed of the engine and the difference between the actual rotational speed of the electric motor and the target rotational speed of the engine decreases, wherein a ratio of the tenth acceleration to the fourteenth acceleration is greater than a ratio of the ninth acceleration to the thirteenth acceleration and is less than the preset ratio; controlling the output torque of the electric motor to be a non-positive value in a case where the actual rotation speed of the electric motor is less than the target rotation speed of the engine and greater than or equal to the target rotation speed of the electric motor; controlling the output torque of the motor to be a positive value and to increase at a fifteenth acceleration when the actual rotation speed of the motor is less than the target rotation speed of the motor and the difference between the target rotation speed and the actual rotation speed of the motor increases, wherein the ratio of the eleventh acceleration to the fifteenth acceleration is greater than the preset ratio; or under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is reduced, controlling the output torque of the motor to be a positive value and to be increased at a sixteenth acceleration, wherein the ratio of the sixteenth acceleration to the twelfth acceleration is greater than the preset ratio and less than the ratio of the eleventh acceleration to the fifteenth acceleration.

First, in the case where the actual rotational speed of the motor/generator is greater than the target rotational speed thereof, it can be divided into two cases, that is, the difference between the actual rotational speed and the target rotational speed is increased and decreased.

In one embodiment, in the case where the actual rotational speed of the motor/engine is greater than the target rotational speed of the engine (e.g., 2000rpm) and the difference between the actual rotational speed of the motor and the target rotational speed (e.g., 1950rpm) increases, the fuel injection amount of the engine is controlled by the first controller (e.g., engine controller 2 shown in fig. 2) to decrease at a ninth acceleration, and at the same time, the output torque of the motor is controlled by the second controller (e.g., motor controller 3 shown in fig. 2) to have a negative value and to decrease at a thirteenth acceleration (which may also be expressed as controlling the power generation torque of the motor to increase at the thirteenth acceleration). Wherein a ratio of the ninth acceleration to the thirteenth acceleration is less than a preset ratio.

That is, when the load is decreased such that the actual rotational speed of the motor/engine is greater than the target rotational speed of the generator (e.g., 2000rpm) and the difference is gradually increased, since the target rotation speed of the motor (e.g., 1950rpm) is less than the target rotation speed of the generator (e.g., 2000rpm), the difference between the actual rotation speed of the motor and its target rotation speed (e.g., 1950rpm) is greater, thus, motor controller 3 responds faster than engine controller 2, so that the ratio K5 of the acceleration of decrease in the fuel injection quantity of the engine to the acceleration of decrease in the output torque of the motor (i.e., the acceleration of increase in the power generation torque) is smaller than K1 (since K1 is smaller (e.g., much smaller) than K0, K5 is also smaller (e.g., much smaller) than K0), thus, the electric motor 5 contributes more to the reduction of the output torque (i.e., the electric motor is in a power generation state), and the fuel injection amount of the engine is mainly used as the main power source.

In one embodiment, in the case where the actual rotation speed of the electric motor is greater than the target rotation speed of the engine and the difference between the actual rotation speed of the electric motor and the target rotation speed of the engine decreases, the fuel injection amount of the engine is controlled to decrease at a tenth acceleration by the first controller (e.g., engine controller 2 shown in fig. 2), and at the same time, the output torque of the electric motor is controlled to be a negative value and to decrease at a fourteenth acceleration by the second controller (e.g., motor controller 3 shown in fig. 2) (which may also be expressed as controlling the power generation torque of the electric motor to increase at the fourteenth acceleration). Wherein a ratio of the tenth acceleration to the fourteenth acceleration is greater than a ratio of the ninth acceleration to the thirteenth acceleration and (the ratio of the tenth acceleration to the fourteenth acceleration) is less than the preset ratio.

That is, when the load is decreased such that the actual rotational speed of the motor/engine is greater than the target rotational speed of the engine (e.g., 2000rpm) and the difference is gradually decreased, since the target rotational speed of the motor (e.g., 1950rpm) is less than the target rotational speed of the generator (e.g., 2000rpm), the difference between the actual rotational speed of the motor and its target rotational speed (e.g., 1950rpm) is greater, thus, the motor controller 3 responds faster than the engine controller 2 (but slower than that of the previous embodiment), so that the ratio K6 of the acceleration at which the fuel injection amount of the engine is reduced to the acceleration at which the motor output torque is reduced (i.e., the acceleration at which the power generation torque is increased) is smaller than K2 (since K2 is smaller than K0, K6 is also smaller than K0) and K6 is larger than K5, accordingly, the electric motor 5 contributes much to the reduction of the output torque (i.e., the electric motor is in a power generation state), and the fuel injection amount of the engine is mainly used as the main power source at this time.

Second, for a case where the actual rotation speed of the motor/generator is less than the target rotation speed of the engine (e.g., 2000rpm), it can be divided into two cases where the actual rotation speed of the motor/generator is greater than or equal to the target rotation speed of the motor (e.g., 1950rpm) and where the actual rotation speed of the motor/generator is less than the target rotation speed of the motor (e.g., 1950 rpm).

In one embodiment, in the case where the actual rotation speed of the electric motor is less than the target rotation speed of the engine and greater than or equal to the target rotation speed of the electric motor, the following two cases are discussed: the first situation is as follows: if the difference between the target rotation speed of the engine and the actual rotation speed of the electric motor increases, the first controller (e.g., the engine controller 2 shown in fig. 2) controls the fuel injection amount of the engine to increase at the eleventh acceleration, and the second controller (e.g., the electric motor controller 3 shown in fig. 2) controls the output torque of the electric motor to be a non-positive value. Case two: if the difference between the target rotation speed of the engine and the actual rotation speed of the electric motor is reduced, the first controller (such as the engine controller 2 shown in fig. 2) controls the fuel injection amount of the engine to increase at the twelfth acceleration, and simultaneously, the second controller (such as the electric motor controller 3 shown in fig. 2) controls the output torque of the electric motor to be a non-positive value.

That is, when the load is increased such that the actual rotation speed of the motor/engine is less than the target rotation speed of the generator (e.g., 2000rpm) and greater than or equal to the target rotation speed of the motor (e.g., 1950rpm), since the actual rotation speed of the motor/engine is greater than or equal to the target rotation speed, no motor output is required, and it is only necessary to respond to the increase in the load by increasing the fuel injection amount of the engine.

In one embodiment, where the actual speed of the motor/generator is less than the target speed of the motor (e.g., 1950rpm), the discussion is divided into the following two scenarios.

The first situation is as follows: if the difference between the target rotation speed (e.g., 1950rpm) and the actual rotation speed of the electric motor increases, the fuel injection amount of the engine is controlled by the first controller (e.g., the engine controller 2 shown in fig. 2) to increase at the eleventh acceleration, and at the same time, the output torque of the electric motor is controlled by the second controller (e.g., the motor controller 3 shown in fig. 2) to be a positive value and to increase at the fifteenth acceleration. Wherein a ratio of the eleventh acceleration to the fifteenth acceleration is greater than the preset ratio.

That is, when the load is increased such that the actual rotational speed of the electric motor is less than its target rotational speed (for example, 1950rpm) and the difference is gradually increased, the engine controller 2 responds faster than the motor controller 3 such that the ratio K7 of the acceleration at which the amount of fuel injected by the engine is increased to the acceleration at which the output torque of the electric motor is increased is greater (for example, much greater) than K0, whereby the engine contributes much to the increase in the output torque, that is, the amount of fuel injected by the engine is mainly used as the main power source; while the motor responds at a slower speed, increasing the output torque, which is energized as auxiliary power, i.e. the motor is in the motoring state.

Case two: if the difference between the target rotation speed (e.g., 1950rpm) and the actual rotation speed of the motor is decreased, the fuel injection amount of the engine is controlled to be increased at a twelfth acceleration by the first controller (e.g., engine controller 2 shown in fig. 2), and simultaneously, the output torque of the motor is controlled to be a positive value and to be increased at a sixteenth acceleration by the second controller (e.g., motor controller 3 shown in fig. 2). Wherein a ratio of the sixteenth acceleration to the twelfth acceleration is greater than the preset ratio and less than a ratio of the eleventh acceleration to the fifteenth acceleration.

That is, when the load is increased so that the actual rotation speed of the motor is less than its target rotation speed (e.g., 1950rpm) and the difference gradually decreases, the engine controller 2 responds faster than the motor controller 3 (but slower than that of the previous embodiment) so that the ratio K8 of the acceleration at which the amount of fuel injected by the engine increases to the acceleration at which the output torque of the motor increases is greater than K0 and K8 is less than K7, whereby the engine contributes more to the increase in output torque, i.e., the amount of fuel injected by the engine is mainly the main power source; while the motor responds at a slower speed, increasing the output torque, which is energized as auxiliary power, i.e. the motor is in the motoring state.

The cooperative control strategy can be realized by adopting a segmented PID or a fuzzy control algorithm. The present embodiment employs a coordinated control strategy to control the engine and the electric motor, and sets the engine to be sensitive to an increase in load and the electric motor to be sensitive to a decrease in load, thereby enhancing the characteristics of the engine as the primary power. The entire vehicle is then powered by the hydraulic pump 7 via the power coupling 6 in fig. 2.

It should be noted that each acceleration in the above embodiments may be a fixed value, or may be a variable (generally, each acceleration is set as a variable based on the influence of the actual operating conditions, the load, and the like of the aerial work device).

A detailed description will be given below of a specific process in which the second controller controls the output torque of the electric motor to be a negative value and to be decreased (i.e., the charging torque is increased).

In practical applications, the SOC-based control strategy is prone to cause overvoltage problems due to inaccurate SOC estimation. In order to solve the phenomenon that the charging process frequently generates overvoltage due to inaccurate SOC estimation, charging power control based on the voltage of the power supply is proposed in the present embodiment.

In one embodiment, the second controller for controlling the output torque reduction of the motor comprises: controlling an output torque reduction of the electric motor using a charging power control strategy.

Specifically, the second controller for controlling the output torque reduction of the electric motor using a charging power control strategy may include: controlling an output torque of the motor to be reduced to pre-charge the power supply with a first charging current in a case where a voltage of the power supply is greater than a first voltage and less than a second voltage, wherein the second voltage is less than a charge cutoff voltage of the power supply; under the condition that the voltage of the power supply is greater than the second voltage and less than a third voltage, controlling the output torque of the motor to be reduced so as to perform constant current charging on the power supply by adopting a second charging current, wherein the second charging current is greater than the first charging current; or controlling the output torque of the motor to be reduced according to the current of the power supply in the case where the voltage of the power supply is greater than or equal to the third voltage.

For the case where the voltage of the power supply is greater than or equal to the third voltage, the second controller for controlling the output torque of the motor to be reduced according to the current of the power supply may include: controlling an output torque of the motor to be reduced to perform constant-voltage charging of the power supply with a third voltage in a case where a voltage of the power supply is greater than or equal to the third voltage and a charging current of the power supply is greater than a third charging current, wherein the third charging current is less than the first charging current; or controlling the output torque of the motor to be reduced to stop charging the power supply in a case where the voltage of the power supply is greater than or equal to the third voltage and the charging current of the power supply is less than or equal to the third charging current.

A specific control procedure in which the second controller controls the output torque of the electric motor to be a negative value and to be decreased will now be described by taking fig. 5 as an example.

Wherein the first voltage may be 1.5 × N V; the second voltage may be 1.9 × N V; the third voltage may be 2.4 × N V, and N may be the number of individual ones of the power supplies. And wherein the first charging current I_c1May be 2% C₂₀(ii) a The second charging current I_c2Can be in the interval (10% C)₂₀,25％C₂₀) Any value of (a); the third charging current I_c3May be 1.5% C₂₀，C₂₀Is the capacity of the power supply. Of course, the first voltage, the second voltage, the third voltage, the first charging current, the second charging current and the third charging current in the present invention are not limited to the specific data listed above, and they can be respectively set according to specific requirements.

A specific control process in which the second controller controls the output torque of the electric motor to be decreased may include steps S501 to S507, as shown in fig. 5.

Step S501, determining whether 1.5 × N V < Uc <1.9 × N V is true, if yes, executing step S502; otherwise, step S503 is executed.

Wherein Uc is the voltage of the power supply.

Step S502, with I_c1＝2％C₂₀The power supply is precharged.

Step S503, determining whether Uc <2.4 × N V is equal to or greater than 1.9 × N V, if yes, executing step S504; otherwise, step S505 is executed.

Step S504, with I_c2＝20％C₂₀And carrying out constant current charging on the power supply.

Step S505, determine Ic>1.5％C₂₀If yes, go to step S506; otherwise, step S507 is executed.

Wherein Ic is the current of the monomer power supply.

Step S506, with U_a2.4 × N V constant voltage charge the power supply.

Wherein, U_aIs the charging voltage. Of course, the constant voltage charging is performed by controlling the charging within a preset fluctuation range of 2.4 × N V (for example, fluctuation of 1% up and down of 2.4 × N V).

In step S507, the power supply is stopped from being charged.

In the embodiment, the charging voltage is controllable, so that the overvoltage alarm phenomenon is effectively avoided. Therefore, the strategy of the segmented charging is also beneficial to prolonging the service life of the battery.

Specifically, the following describes how each operation mode of the hybrid power is automatically switched under the cooperative control strategy in the present embodiment, taking the tower arm ascending process of the crank-arm type aerial work platform as an example.

1. When U is turned<U_co(namely the power supply voltage is less than the charging cut-off voltage), the target rotating speed of the engine in the tower arm rising process is 2600rpm of the maximum power point, and a preset rotating speed difference n is taken_diffAt 50rpm, the target speed of the motor is 2550 rpm.

When the tower arm angle is less than 35 degrees, once the power required by the tower arm to rise exceeds the maximum power of the engine, even if the fuel injection amount controlled by an engine controller reaches the maximum, the fuel injection amount cannot meet the torque required by the rise, and the actual rotating speed of the engine is reduced from 2600 rpm. After the actual rotating speed of the engine is reduced to be below 2550rpm, the method is executed through the scheme of the cooperative control strategy: the engine controller responds quickly to output maximum power (which can be achieved by setting the response parameters of the engine), and the motor controller adjusts the output torque to supplement the remaining required power according to load changes to maintain the actual speed at 2550rpm by increasing the output torque. The power system is operated in a hybrid mode, and the engine and the peak battery simultaneously provide power.

When the tower arm angle is between 35 and 40 degrees, once the power required by the tower arm rising is equal to the maximum power of the engine, the motor controller can finally adjust the output torque to 0 according to the change of the rotating speed, and the rotating speed of the engine is kept to be 2550 rpm. At the moment, the engine works independently to provide energy for the whole vehicle, and the power system works in a single-engine working mode.

When the tower arm angle is greater than 40 deg., once the power required for the tower arm to rise is less than the maximum power of the engine, the engine provides more torque than is required for the rise, at which time the engine speed rises. As the actual rotating speed of the engine/motor is higher than the target rotating speed of the motor, the motor works in a generator state and the motor controller controls the generated current to charge the power supply by limiting the torque value according to the scheme cooperative control strategy. At the moment, the power system works in a charging mode, and the engine provides energy required by the whole vehicle action and energy required by charging.

It should be noted that the above-mentioned tower arm angle range is only used as an example, and actually the tower arm angle range is related to various complex factors such as actual working conditions and load conditions, and since the relationship between the specific control strategy of the working mode of the corresponding power system and the tower arm angle range is not the improvement of the present invention, it is not discussed in detail herein.

2. If U is more than or equal to U_co(i.e., the voltage of the power source is equal to or greater than the charge cutoff voltage), at which the target rotational speed of the motor is equal to the target rotational speed of the engine.

When the load is increased, the actual rotating speed of the engine is reduced, the engine controller quickly reacts, and the fuel injection quantity is increased to provide energy as main power; the motor controller responds at a relatively slow speed, increasing the output torque, providing energy as auxiliary power. When the load is reduced, the actual rotating speed of the engine is increased, the motor controller responds quickly, the output torque is reduced, and the engine still provides energy as the main power. The motor operates in a motor state and limits the generated torque to zero.

Because the aerial work platform does not have mechanical brake equipment, there is not the braking mode when hybrid operation, so hybrid aerial work platform has four kinds of working modes only: a single motor mode, a hybrid mode, a single motor mode, and a charging mode.

Therefore, no matter the charge state of the power supply, the crank arm type aerial work platform always takes the engine as a basic power source and the power supply as an auxiliary power source.

It should be noted that both the target rotational speed acquisition device and the actual rotational speed acquisition device in the embodiments of the present invention may be integrated in the vehicle control unit 1, or may be independent components.

In summary, the present invention creatively controls the fuel injection amount of the engine and the output torque of the electric motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the electric motor so as to maintain the actual rotating speed of the electric motor/engine within a preset range. Thus, the present invention employs a coordinated control strategy to achieve automatic distribution of powertrain torque without requiring estimation of demand power and power supply discharge power.

An embodiment of the invention further provides an energy control method. The energy control method may include: acquiring a target rotating speed of the motor; acquiring the actual rotating speed of the motor; and controlling the fuel injection quantity of the engine and the output torque of the motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor so as to maintain the actual rotating speed of the motor within a preset range. Wherein the engine is coaxially coupled with the motor.

The embodiment of the invention also provides high-altitude operation equipment. The aerial work apparatus may comprise: the energy control system.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. An energy control system, comprising:

target rotation speed obtaining means for obtaining a target rotation speed of the motor;

actual rotational speed acquisition means for acquiring an actual rotational speed of the motor; and

and the control device is used for controlling the fuel injection quantity of the engine and the output torque of the motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor so as to maintain the actual rotating speed of the motor within a preset range, wherein the engine is coaxially coupled with the motor.

2. The energy control system according to claim 1, wherein the target rotational speed obtaining means includes:

the first target rotating speed acquisition module is used for acquiring a target rotating speed of the engine; and

and the second target rotating speed acquisition module is used for determining the target rotating speed of the engine as the target rotating speed of the motor.

3. The energy control system of claim 2, wherein the control device comprises:

the first controller is used for controlling the following changes of the fuel injection quantity of the engine by adopting the cooperative control strategy:

controlling the fuel injection amount of the engine to be reduced under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor; or

Controlling an amount of fuel injection of the engine to be increased in a case where an actual rotation speed of the electric motor is less than a target rotation speed of the electric motor, an

A second controller for controlling the following changes in output torque of the electric motor using the cooperative control strategy:

controlling the output torque of the motor to be a negative value and to be reduced in the case where the actual rotation speed of the motor is greater than the target rotation speed of the motor; or

And controlling the output torque of the motor to be a positive value and to be increased when the actual rotating speed of the motor is less than the target rotating speed of the motor.

4. The energy control system of claim 2, wherein the control device comprises:

controlling the fuel injection quantity of the engine to be reduced at a first acceleration under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is increased; or

Controlling an injection amount of the engine to be decreased at a second acceleration in a case where an actual rotation speed of the electric motor is greater than a target rotation speed of the electric motor and a difference between the actual rotation speed and the target rotation speed of the electric motor is decreased, and

controlling the output torque of the motor to be a negative value and to be reduced at a fifth speed under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is increased, wherein the ratio of the first acceleration to the fifth speed is smaller than a preset ratio; or

And under the condition that the actual rotating speed of the motor is greater than the target rotating speed of the motor and the difference value between the actual rotating speed and the target rotating speed of the motor is reduced, controlling the output torque of the motor to be a negative value and to be reduced by a sixth acceleration, wherein the ratio of the second acceleration to the sixth acceleration is greater than the ratio of the first acceleration to the fifth acceleration and is smaller than the preset ratio.

5. The energy control system of claim 2, wherein the control device comprises:

controlling the fuel injection amount of the engine to increase at a third acceleration under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased; or

Controlling an amount of fuel injected by the engine to increase at a fourth acceleration in a case where an actual rotation speed of the electric motor is less than a target rotation speed of the electric motor and a difference between the target rotation speed and the actual rotation speed of the electric motor decreases, an

controlling the output torque of the motor to be a positive value and to increase at a seventh acceleration under the condition that the actual rotating speed of the motor is less than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is increased, wherein the ratio of the third acceleration to the seventh acceleration is greater than a preset ratio; or

And under the condition that the actual rotating speed of the motor is smaller than the target rotating speed of the motor and the difference value between the target rotating speed and the actual rotating speed of the motor is reduced, controlling the output torque of the motor to be a positive value and to be increased by an eighth acceleration, wherein the ratio of the eighth acceleration to the fourth acceleration is larger than the preset ratio and smaller than the ratio of the third acceleration to the seventh acceleration.

6. The energy control system of claim 3 wherein the second controller is configured to control the output torque of the electric motor to be negative and decreasing comprises:

controlling an output torque reduction of the electric motor using a charging power control strategy.

7. The energy control system of claim 6, wherein the second controller to control the output torque reduction of the electric motor using a charging power control strategy comprises:

controlling an output torque of the motor to be reduced to pre-charge the power supply with a first charging current in a case where a voltage of the power supply is greater than a first voltage and less than a second voltage, wherein the second voltage is less than a charge cutoff voltage of the power supply;

under the condition that the voltage of the power supply is greater than the second voltage and less than a third voltage, controlling the output torque of the motor to be reduced so as to perform constant-current charging on the power supply by adopting a second charging current, wherein the second charging current is greater than the first charging current; or

Controlling the output torque of the motor to be reduced according to the current of the power supply in a case where the voltage of the power supply is greater than or equal to the third voltage.

8. The energy control system of claim 7, wherein the second controller for controlling the output torque of the electric motor to decrease in accordance with the current of the power source comprises:

controlling an output torque of the motor to be reduced to perform constant-voltage charging of the power supply with a third voltage in a case where a voltage of the power supply is greater than or equal to the third voltage and a charging current of the power supply is greater than a third charging current, wherein the third charging current is less than the first charging current; or

Controlling the output torque of the motor to decrease to stop charging the power supply, in a case where the voltage of the power supply is greater than or equal to the third voltage and the charging current of the power supply is less than or equal to the third charging current.

9. An energy control method, characterized in that the energy control method comprises:

acquiring a target rotating speed of the motor;

acquiring the actual rotating speed of the motor; and

and controlling the fuel injection quantity of an engine and the output torque of the motor by adopting a cooperative control strategy according to the target rotating speed and the actual rotating speed of the motor so as to maintain the actual rotating speed of the motor within a preset range, wherein the engine is coaxially coupled with the motor.

10. An aerial work apparatus, comprising: the energy control system of any of claims 1-8.