A method for automatically determining the working state of an electric fork truck and controlling the normal power output

Abstract

The present application belongs to the field of electric fork truck, and particularly relates to a normal power output control method for automatically judging the working state of an electric fork truck, which comprises: powering on the device, judging the running state of the device; if in dynamic mode, always maintaining normal power output; if in static mode, collecting the battery voltage V and comparing it with the pre-set normal power off voltage threshold V0, if V >= V0, sending the control command of normal power output to the normal power output control module; if V < V0 and the duration T, sending the control command of normal power off to the normal power output control module; the normal power output control module outputs the corresponding enable signal to the drive module; the drive module drives the controlled module to work; when the counting value of the timing module reaches the pre-set value, the timing module automatically wakes up the main control module. The present application sets the normal power off threshold in combination with the running state of the device and the power supply characteristics, so that the threshold is more reasonable.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of electric forklifts, and particularly relates to a normal power output control method for automatically judging the working state of an electric forklift. BACKGROUND

[0002] After the device or system is powered off and hibernates, all functional modules are closed, which is not conducive to the user to collect necessary information of the device, and is not conducive to the device to monitor the abnormality and timely processing. However, if the device is always kept in a working state to ensure the normal operation of the required functions, the power consumption will become very large. The present application realizes the automatic judgment of the running state of the device by automatically collecting and judging the characteristic parameters of the device in operation, and realizes the output of normal power in the hibernation state of the device in combination with the characteristics of the power supply source of the device, by using the normal power output control method and logic, while ensuring the closing of the normal power output in necessary cases. SUMMARY

[0003] In order to make up for the deficiencies of the prior art, the present application provides a normal power output control method for automatically judging the working state of an electric forklift.

[0004] A normal power output control method for automatically judging the working state of an electric forklift, comprising the following steps:

[0005] Step 1, powering on the device to judge the running state of the device;

[0006] If in the dynamic mode, the normal power output is always kept to control the controlled module to work normally;

[0007] If in the static mode, the main control module collects the battery voltage V and compares it with the pre-set normal power closing voltage threshold V0, if V >= V0, the main control module sends the control command of normal power output to the normal power output control module; if V < V0 and the duration T, the main control module sends the control command of closing the normal power output to the normal power output control module;

[0008] Step 2, the normal power output control module receives the control command of the main control module and outputs the corresponding enable signal to the drive module;

[0009] Step 3, the drive module drives the controlled module to work after receiving the enable signal;

[0010] Step 4, comprising:

[0011] Step 4.1, when the device is powered off, the main control module enters hibernation;

[0012] Step 4.2, the timing module starts working after the main control module enters hibernation, and when the counting value of the timing module reaches the pre-set value, the timing module wakes up the main control module;

[0013] Step 4.3, the main control module is woken up by the timing module, and automatically wakes up the static working mode, so the battery voltage is continuously detected, if the battery voltage V is still greater than or equal to the normal power-off voltage threshold V0, the normal power output is maintained and step 4.4 is entered; if the battery voltage V is less than the normal power-off voltage threshold V0, the normal power output and the timing module are turned off, the main control module is no longer automatically woken up, but waits for manual awakening and charging to make the battery voltage higher than the normal power-off voltage threshold to restore the normal power output and automatic awakening function;

[0014] Step 4.4, when the main control module is woken up by the timing module, the timing module starts timing at the same time, when the awakening time reaches the pre-set time length, the main control module enters sleep again and returns to step 4.2.

[0015] Further, in step 2, the enable signal output by the normal power output control module is not affected by whether the main control module works or not, and the normal power output control module always maintains the original enable signal before receiving the opposite control instruction from the main control module.

[0016] Further, in step 3, the driving module is powered by the power supply alone, and when the main control module is powered off and sleeps, as long as the enable signal exists, the driving module can still drive the controlled module to work normally.

[0017] Further, the method for judging the device running state in step 1 includes the following steps:

[0018] Step 1.1, the main control module collects the data of the power supply, and dynamically determines the current division threshold of the dynamic and static working mode;

[0019] Step 1.2, the main control module judges the dynamic and static mode.

[0020] Further, step 1 includes:

[0021] Step 1.1.1, the main control module collects the current I and voltage V of the power supply;

[0022] Step 1.1.2, the main control module divides the continuously collected current data into two data sets according to the pre-set initial current division threshold I0: the dynamic current data set and the static current data set The expression is divided into:

[0023]

[0024]

[0025] Step 1.1.3, when the length m of the data set and the length n of the data set After the length n of both data sets exceeds the pre-set data length threshold L, the L most recently obtained data in both data sets are intercepted, and the head data beyond L is discarded, and the two data sets are reacquired:

[0026]

[0027]

[0028] Step 1.1.4, the mean μ1 of the current data set and the mean μ2 of the current data set , and the standard deviation σ1 of the current data set and the standard deviation σ2 of the current data set are calculated respectively, and the expression is:

[0029]

[0030]

[0031]

[0032]

[0033] Step 1.1.5: According to the calculated mean μ1 and μ2, update the dynamic-static current differentiation threshold I0, and the expression is:

[0034]

[0035] Further, the step 1.1 further comprises:

[0036] With the use of the electric forklift, the main control module continuously collects new current data, and the new current data is divided into the dynamic current data set or the static current data set according to the rolling updated dynamic-static differentiation threshold I0, at the same time, the current data set and always maintain the number of current data as L, and whenever or obtains a new data, it will eliminate the oldest current data from the data set, so as to realize the rolling update of the data set elements, and after the data set is updated, the mean and the standard deviation are also calculated and updated.

[0037] Further, the step 1.2 comprises:

[0038] When Q consecutive current data [I1, I2, I3…I i , …I QQ current data satisfy the following conditions:

[0039] μ1-σ1≤I i ≤μ1+σ1

[0040] The power fork truck is determined to enter the dynamic mode;

[0041] When Q current data [I1, I2, I3…I i , …I Q ] are continuously collected, and the Q current data satisfy:

[0042] μ2-σ2≤I i ≤μ2+σ2

[0043] The power fork truck is determined to enter the static mode.

[0044] Compared with the prior art, the present application has the following advantages:

[0045] 1) The present application sets the always-on-off threshold according to the running state of the device and the power supply characteristics, making the threshold more reasonable;

[0046] 2) The present application collects, processes and monitors the power supply data by regularly waking up the main control module, which meets the monitoring requirements and reduces the device power consumption;

[0047] 3) The present application sets different always-on control logic for different running states according to the actual running state of the device, which is more in line with the actual running requirements of the device;

[0048] 4) The present application can be applied to any device and system that needs to be powered by always-on to ensure that the specific function modules of the device remain normal during power-off hibernation;

[0049] 5) The device running state judgment method in the present application can automatically analyze the characteristics of the device in different working modes and calculate reasonable device working mode threshold, which can meet the working mode differentiation requirements of different models of devices or the same model of devices in different use states and life cycles, has the characteristics of automatic learning and analysis, and has strong applicability. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 is the flow chart of the present application;

[0051] Figure 2 is the battery control system circuit relationship diagram of the present application;

[0052] Figure 3 is the device running state judgment method flow chart in the present application;

[0053] Figure 4The process flow of step 1.1 in the present application. DETAILED DESCRIPTION

[0054] In the description of the present application, it should be understood that the terms "one end", "the other end", "outer side", "upper", "inner side", "horizontal", "coaxial", "central", "end", "length", "outer end" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0055] In the present application, the normal power output control module is controlled by the master control module, which is responsible for outputting an enable signal that can maintain the original state after the device is powered off and hibernated, activating the drive module to drive those controlled modules that still need to be kept working during power-off hibernation, so that they can work normally. The master control module is responsible for collecting and processing data of the power supply. When a special situation (such as low battery power or other situations requiring normal power output to be turned off) is monitored, the master control module sends a normal power output off command to the normal power output control module to cut off the normal power output. If no special situation is monitored within a certain period of time, the master control module actively enters a hibernation state to reduce the power consumption of the device, and at the same time the timing module starts to work. The timing module will start timing after the master control module enters the hibernation state, and will wake up the master control module after a certain period of time. When the master control module monitors the data of the power supply, it will set a reasonable normal power off threshold in combination with the running state of the device and the characteristics of the power supply.

[0056] The present application will be further described below with reference to the accompanying drawings.

[0057] Please refer to Figures 1-4 A normal power output control method for automatically determining the working state of an electric forklift, comprising the following steps:

[0058] Step 1: power on the device and determine the running state of the device.

[0059] If in dynamic mode, always keep normal power output to control the normal work of the controlled module;

[0060] If in static mode, the master control module collects the battery voltage V and compares it with the pre-set normal power off voltage threshold V0. If V≥V0, the master control module sends a normal power output control command to the normal power output control module. If V

[0061] The voltage threshold V0 for closing the normal power output, i.e. the minimum single cell voltage of the lithium iron phosphate battery, is a reasonable threshold derived from the discharge characteristics of the lithium iron phosphate battery. When the electric forklift is in a static state, if the minimum single cell voltage of the lithium iron phosphate battery inside is monitored to be less than the voltage threshold V0 and the duration reaches the time threshold T, it indicates that the power of the battery cell with the lowest power in the battery pack has approached zero, and therefore the normal power output should be turned off in time, and the timing wake-up function is also turned off to prevent the battery power from being completely discharged.

[0062] Step 2, the normal power output control module receives the control command of the master control module and outputs the corresponding enable signal to the drive module. The enable signal is not affected by whether the master control module is working or not. Before receiving the opposite control command from the master control module, the normal power output control module always maintains the original enable signal.

[0063] Step 3, after receiving the enable signal, the drive module drives the controlled module to work. The drive module is powered by a separate power supply, so when the master control module is powered off and hibernates, as long as the enable signal exists, the drive module can still drive the controlled module to work normally.

[0064] Step 4, including:

[0065] Step 4.1, when the device is powered off, the master control module enters hibernation;

[0066] Step 4.2, the timing module starts working after the master control module enters hibernation. When the timing module counts to a pre-set value, the timing module wakes up the master control module;

[0067] Step 4.3, after the master control module is woken up by the timing module, it automatically wakes up the static working mode, and therefore continuously detects the battery voltage. If it is detected that the battery voltage V is still greater than or equal to the normal power-off voltage threshold V0, the normal power is maintained and step 4.4 is entered. If it is detected that the battery voltage V is less than the normal power-off voltage threshold V0, the normal power output and the timing module are turned off, and the master control module no longer automatically wakes up, but waits for manual awakening and charging to make the battery voltage higher than the normal power-off voltage threshold to restore the normal power output and automatic wake-up function;

[0068] Step 4.4, when the master control module is woken up by the timing module, the timing module starts timing at the same time. When the wake-up time reaches a pre-set time length, the master control module enters hibernation again and returns to step 4.2.

[0069] Taking an electric forklift powered by lithium iron phosphate batteries as an example: the discharge operation of an electric forklift can be divided into dynamic and static states. Dynamic refers to the forklift being in operation, where it needs to carry heavy loads and move, resulting in a large current in the working circuit. Static refers to the forklift being stationary or in a power-off sleep state, where the operating current is very small or zero. The conventional way to distinguish between the dynamic and static operating modes of a forklift is to set a fixed current threshold. When the current detected in the working circuit exceeds the preset current threshold, it is considered to be in a dynamic state; when the current detected in the working circuit is less than the preset current threshold, it is considered to be in a static state.

[0070] However, in practical applications, due to differences in power and static power consumption of onboard equipment among different models of electric forklifts, it is difficult to distinguish the operating modes of different models using a fixed current threshold. Furthermore, even for the same model, aging or malfunctions in equipment and wiring can cause changes in the current threshold for distinguishing between dynamic and static operating modes. Therefore, the standard for distinguishing the dynamic and static operating modes of electric forklifts should be dynamically changing and adaptive.

[0071] Therefore, the present invention also proposes a method for determining the operating status of a device, such as... Figures 3-4 This includes the following steps:

[0072] Step 1.1: The main control module collects data from the power supply and dynamically determines the current distinction threshold between dynamic and static operating modes.

[0073] Step 1.1 includes:

[0074] Step 1.1.1: The main control module collects the current I and voltage V of the power supply.

[0075] Step 1.1.2: The main control module, according to the preset initial current discrimination threshold I0, processes the continuously collected current data. It consists of two datasets: dynamic current dataset. and static current dataset The expression is:

[0076]

[0077]

[0078] Step 1.1.3, when the dataset and If both the lengths m and n exceed the preset data length threshold L, then the L most recently obtained data items from the two datasets are truncated, and the header data exceeding length L is discarded. At this point, two datasets are obtained again, expressed as:

[0079]

[0080]

[0081] Step 1.1.4, calculate the mean μ1 and μ2, and the standard deviation σ1 and σ2 of the current data set and respectively, the expression is:

[0082]

[0083]

[0084]

[0085]

[0086] Step 1.1.5, update the dynamic-static current separation threshold I0 according to the calculated mean μ1 and μ2, the expression is:

[0087]

[0088] As the electric forklift is used, the main control module continuously collects new current data, and the new current data is divided into the dynamic current data set or the static current data set according to the rolling updated dynamic-static separation threshold I0, at the same time, the current data sets and always maintain their current data number as L, therefore, whenever or obtains a new data, it will eliminate the oldest current data from the data set, so as to realize the rolling update of the data set elements. After the data set is updated, its mean and standard deviation are also calculated and updated.

[0089] Step 1.2, the main control module makes dynamic-static mode judgment.

[0090] Step 1.2 includes:

[0091] When the device is in automatic wake-up state, it is directly considered that the device is in static working mode;

[0092] When the device is in artificial wake-up state, dynamic-static separation is made according to the following conditions:

[0093] When Q consecutive current data [I1, I2, I3…I i , …I Q ] are collected, and the Q current data meet the following conditions:

[0094] μ1-σ1≤Ii ≤ μ1+ σ1

[0095] Then, it is determined that the electric forklift enters the dynamic mode;

[0096] When Q current data [I1, I2, I3…I i , …I Q ] are continuously collected, and the Q current data satisfy:

[0097] μ2- σ2≤ I i ≤ μ2+ σ2

[0098] Then, it is determined that the electric forklift enters the static mode;

[0099] In other cases, the working mode is kept as the last time.

[0100] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for automatically determining the working state of a power fork truck and controlling the normal power output, characterized in that, It comprises the following steps: Step 1, the device is powered on, and the running state of the device is determined; If in dynamic mode, always keep the normal power output to control the normal work of the controlled module; If in static mode, the master module collects the battery voltage , compares with the pre-set normal power-off voltage threshold , if , the master module sends the control command of normal power output to the normal power output control module; if , and the duration , the master module sends the control command of normal power output to the normal power output control module; The method for determining the running state of the device comprises the following steps: Step 1.1, the main control module collects the data of the power supply and dynamically determines the current threshold of dynamic and static working mode, including: Step 1.1.1, the main control module collects the current I and voltage V of the power supply; Step 1.1.2, the master module divides the initial current threshold according to the preset The continuously collected current data is divided into two data sets: a dynamic current data set and a static current data set , the expression is divided into: ； Step 1.1.3, when the dataset length and dataset length All exceeded the preset data length threshold. Then, extract the most recently obtained data from the two datasets. Data points, and discarded. The header data, excluding the length, is used to re-obtain two datasets: Step 1.1.4, calculate the mean of the current data set Step 1.1.5, calculate the mean of the current data set Step 1.1.6, calculate the standard deviation of the current data set Step 1.1.7, calculate the standard deviation of the current data set , the expression is: ​​​​ Step 1.1.5, updating the mean value calculated and , updating the dynamic-static current discrimination threshold , the expression being: ； Step 1.2, the main control module determines the dynamic and static mode; Step 2, the normal power output control module receives the control command of the main control module and outputs the corresponding enable signal to the drive module; Step 3, after receiving the enable signal, the drive module drives the controlled module to work; Step 4, including: Step 4.1, when the device is powered off, the main control module enters sleep; Step 4.2, the timing module starts working after the main control module enters sleep, and when the counting value of the timing module reaches the pre-set value, the timing module wakes up the main control module; Step 4.3, after the main control module is woken up by the timing module, it continues to detect the battery voltage, if the detected battery voltage is still greater than or equal to the normal power off voltage threshold , it keeps outputting normal power and goes to step 4.4; if the detected battery voltage is less than the normal power off voltage threshold , it turns off the normal power output and the timing module, the main control module will not automatically wake up again, but waits for manual wake up and charging to make the battery voltage higher than the normal power off voltage threshold to restore the normal power output and automatic wake up function; Step 4.4, when the main control module is woken up by the timing module, the timing module starts timing at the same time, and when the wake-up time reaches the pre-set time length, the main control module enters sleep again and returns to step 4.

2.

2. The method according to claim 1, wherein the method is characterized by: In step 2, the enable signal output by the normal power output control module is not affected by whether the main control module works or not, and the normal power output control module always keeps outputting the original enable signal before receiving the opposite control command from the main control module.

3. The method of claim 1, wherein the method further comprises: determining whether the fork truck is in a work state or a non-work state; and outputting power to the motor based on the determined state of the fork truck. In step 3, the drive module is powered by the power supply alone, and as long as there is an enable signal, the drive module can still drive the controlled module to work normally when the main control module is powered off and sleeps.

4. The method of claim 1, wherein the method further comprises: determining whether the power fork truck is in a working state; and outputting power to the power fork truck in the working state. Step 1.1 further comprises: With the use of the electric fork truck, the main control module continuously collects new current data, and the new current data is divided into dynamic and static according to the rolling update threshold While being divided into the dynamic current data set Or the static current data set At the same time, the current data set And Always maintains its current data number Whenever Or A new data is obtained, it will eliminate the oldest current data from the data set, so as to realize the rolling update of the data set elements, and the mean and standard deviation of the updated data set are also calculated and updated.

5. The method of claim 1, wherein the method further comprises: determining whether the power fork truck is in a working state; and outputting power to the power fork truck in the working state. Step 1.2 comprises: When the continuous acquisition of current data , and current data meets the following conditions: If the current I is greater than the threshold, it is determined that the electric forklift enters dynamic mode; When the continuous acquisition of current data , and current data satisfies: If the current I is less than the threshold, it is determined that the electric forklift enters static mode.

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