A kind of detection circuit and its detection method that high voltage negative relay is adhered
Technical field
The invention belongs to the technical fields of relay test, and in particular to a kind of detection that high voltage negative relay is adhered electricity
Road and its detection method.
Background technique
Nowadays, in the high-pressure system of electric car, the state-detection of relay be realize electric car power on safely, under
The important technology of electricity.Electric automobile high-voltage components are more, in actual moving process, when short-circuit failure occurs in components load
When or full-vehicle control timing Design it is unreasonable, high current can be generated on power line leads to relay adhesion, in order to rise safely
See, electric car power on and lower electric process in, it is necessary to relay status is detected.
Wherein, Chinese patent literature discloses a kind of power battery major loop relay fault detecting circuit of electric car
And its detection method (publication number: 106124980 A of CN), comprising: vehicle interface circuit, normally closed low-voltage relay, current limliting electricity
Resistance, high pressure optocoupler, divider resistance, isolated amplifier and power module, normally closed low-voltage relay contact one end and low tension battery
Anode connection, one end are connect by current-limiting resistance with high pressure optocoupler control terminal, and low-voltage relay coil one end connects with ACC grades of power supplys
It connects, one end is connect with low tension battery cathode, and isolated amplifier, power module are powered by low tension battery, divider resistance electricity
Road both ends are connect respectively in the positive contacts of contactor downstream of master and main negative contacts of contactor upstream.Above-mentioned scheme to a certain extent can
Relay adhesion is enough detected, but at least there is also following defects for this scheme: first, logical operation amount is big, influences abnormal anti-
The real-time of feedback;Second, photoelectric device is easy failure, and system reliability is caused to be deteriorated;Third, testing cost are high.
Summary of the invention
It is an object of the present invention to: in view of the deficiencies of the prior art, provide what a kind of high voltage negative relay was adhered
Detection circuit can find whether cathode relay is adhered before battery leads to high-voltage electricity, help to ensure battery system
It works normally, improves the stability and reliability of the circuit system of battery, meanwhile, detect that cathode relay is adhered in advance, energy
The safety for enough improving maintenance personal, helps to prevent personnel from accidentally touching equipment and causing casualty accident.
To achieve the goals above, the present invention adopts the following technical scheme:
A kind of detection circuit that high voltage negative relay is adhered, including battery pack, be connected to the total anode of the battery pack, be total
The positive relay and cathode relay of cathode further include the partial pressure of connection total anode and the cathode relay output end
Circuit, with the bleeder circuit electrical connection A/D converting unit, with the A/D converting unit be electrically connected be isolated communication unit,
And with the micro-control unit that communication unit electrical connection is isolated, the bleeder circuit includes concatenated first resistor unit and the
Two resistance units, one end of the first resistor unit are connected to total anode, the first resistor unit and described second
Voltage acquisition point is provided between resistance unit, the voltage acquisition point is electrically connected with the input terminal of the A/D converting unit, institute
It states between second resistance unit and the output end of the cathode relay with being provided with sample reference.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, first electricity
Hindering unit includes first resistor and second resistance, and the second resistance unit includes 3rd resistor, one end of the first resistor
It is connected to total anode, the voltage acquisition point, the third are provided between the second resistance and the 3rd resistor
Between resistance and the output end of the cathode relay with being provided with the sample reference.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, the A/D turns
The ground terminal for changing unit and the isolation communication unit is electrically connected with the sample reference.A/D converting unit and isolation are logical
Believe unit with same sample reference, can reduce the noise jamming in signal transmission.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, the detection electricity
Road further includes isolated power supply, and the A/D converting unit, the isolation communication unit and the micro-control unit are isolated with described
Power electric connection.The power input of A/D converting unit, isolation communication unit and micro-control unit is connected to isolated power supply,
It can reduce the influence of noise in signal transmission in this way, improve the stability of digital signal.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, the A/D turns
It changes unit, the isolation communication unit, the micro-control unit and passes through clock communication line and data telecommunication line progress data biography
It is defeated.Data telecommunication line SDA is bidirectional data line, and clock communication line SCL is clock line, and data are transmitted in I2C bus, are sent first
Highest order, such as: by host issue enabling signal after, SDA between SCL high period by high level jump be low level, then by
Host sends the data of a byte;Data Transfer Done issues stop signal by host, and SDA is between SCL high period by low
Level jump is high level, i.e. the transmission of realization orderly information.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, it is described anode after
Electric appliance and the cathode relay are single-contact relay.Single-contact relay is relatively simple for structure, facilitates maintenance personal
Circuit is repaired.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, the detection electricity
Road further includes warning device, and the warning device is electrically connected with the micro-control unit.Warning device for prompt operator or
Maintenance personal helps to find that cathode relay is adhered in advance, improves the safety of battery.
As a kind of a kind of improvement for the detection circuit that high voltage negative relay is adhered of the present invention, the microcontroller
Unit is electrically connected with the cathode relay.Micro-control unit can control cathode relay closing or opening.
The second object of the present invention is to additionally provide a kind of detection method that high voltage negative relay is adhered, including as follows
Step:
1) A/D converting unit acquisition electric car is in the voltage Uab in power process between voltage acquisition point and sample reference ground,
Then digital signal is converted analog signals into, and is sent to isolation communication unit;
2) received signal is carried out isolation processing by isolation communication unit, and is sent to micro-control unit;
3) micro-control unit is according to the voltage Uab in power process between voltage acquisition point and sample reference ground, judge cathode after
Whether electric appliance is adhered.
In detection method of the invention, the voltage Uab between step 1) voltage acquisition point and sample reference ground is actually
The voltage at second resistance unit both ends is sampled, A/D converting unit is in real time monitored voltage Uab, and is converted
For digital signal;The communication isolating that communication unit is suitable between complicated circuit is isolated in step 2), can not only improve communication efficiency,
The applicable performance of circuit can also be enhanced;Step 3) can in sample reference generate zero potential reference after disconnecting due to cathode relay
Point, and one end of second resistance unit with sample reference is connected, therefore voltage of the sample reference ground between voltage acquisition point
It can be used for judging whether cathode relay is adhered.
As a kind of a kind of improvement for the detection method that high voltage negative relay is adhered of the present invention, sentence in step 3)
The method that disconnected cathode relay is adhered, includes the following steps:
If entire car controller has sent battery pack power-on command, and Uab > 0, then the cathode relay normally closed is judged;
If entire car controller has sent battery pack power off command, and Uab=0, then judge that the cathode relay normally disconnects;
If entire car controller has sent battery pack power off command, and Uab > 0, then judge that the cathode relay is adhered.
Detailed description of the invention
Fig. 1 is the structural diagram of the present invention.
Fig. 2 is circuit diagram of the invention.
Wherein: 1- battery pack;2- anode relay;3- cathode relay;4- bleeder circuit;5-A/D converting unit;6- every
From communication unit;7- micro-control unit;41- first resistor;42- second resistance;43- 3rd resistor;10- isolated power supply;A- electricity
Press collection point;B- sample reference.
Specific embodiment
As used some vocabulary to censure specific components in the specification and claims.Those skilled in the art answer
It is understood that hardware manufacturer may call the same component with different nouns.This specification and claims are not with name
The difference of title is as the mode for distinguishing component, but with the difference of component functionally as the criterion of differentiation.Such as logical
The "comprising" of piece specification and claim mentioned in is an open language, therefore should be construed to " include but do not limit
In "." substantially " refer within an acceptable error range, those skilled in the art can solve technology within a certain error range
Problem basically reaches technical effect.
In the description of the present invention, it is to be understood that, term " on ", "lower", "front", "rear", "left", "right", level "
The orientation or positional relationship of equal instructions is to be based on the orientation or positional relationship shown in the drawings, be merely for convenience of the description present invention and
Simplify description, rather than the device or element of indication or suggestion meaning must have a particular orientation, with specific orientation construction
And operation, therefore be not considered as limiting the invention.
In invention unless specifically defined or limited otherwise, the arts such as term " installation ", " connected ", " connection ", " fixation "
Language shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or be integrally connected;It can be machine
Tool connection, is also possible to be electrically connected;It can be directly connected, two members can also be can be indirectly connected through an intermediary
Connection inside part.For the ordinary skill in the art, above-mentioned term can be understood in this hair as the case may be
Concrete meaning in bright.
Below in conjunction with attached drawing, invention is further described in detail, but not as a limitation of the invention.
Embodiment 1
As shown in Figure 1 and 2, a kind of detection circuit that high voltage negative relay is adhered, including battery pack 1, it is connected to battery pack
The positive relay 2 and cathode relay 3 of 1 total anode, total cathode further include connecting total anode and 3 output end of cathode relay
Bleeder circuit 4, with bleeder circuit 4 be electrically connected A/D converting unit 5, with A/D converting unit 5 electrical connection communication unit is isolated
Member 6 and with micro-control unit 7 that the electrical connection of communication unit 6 be isolated, bleeder circuit 4 includes concatenated first resistor unit and the
Two resistance units, one end of first resistor unit are connected to total anode, and second resistance unit is connected to the output of cathode relay 3
End is provided with voltage acquisition point a, voltage acquisition point a and A/D converting unit 5 between first resistor unit and second resistance unit
Input terminal electrical connection, with being provided with sample reference b between second resistance unit and the output end of cathode relay 3.
Wherein first resistor unit primarily serves the effect of partial pressure, therefore the requirement of the resistance value of first resistor unit is very big, and the
The resistance value of two resistance units is relatively small.In view of the pressure resistance of resistance, in this present embodiment, first resistor unit takes two electricity
Hinder concatenated design.Specifically, first resistor unit includes first resistor 41 and second resistance 42, second resistance unit includes the
Three resistance 43, that is to say, that bleeder circuit 4 includes first resistor 41, second resistance 42 and the 3rd resistor 43 being sequentially connected in series, the
One end of one resistance 41 is connected to total anode, and voltage acquisition point a is provided between second resistance 42 and 3rd resistor 43, and voltage is adopted
Collection point a is electrically connected with the input terminal of A/D converting unit 5, is provided with and is adopted between 3rd resistor 43 and the output end of cathode relay 3
Sample is with reference to ground b.Since first resistor 41 and second resistance 42 primarily serve the effect of partial pressure, in this present embodiment, first resistor
41 resistance value is 2M Ω, and the resistance value of second resistance 42 is 2M Ω, and the resistance value of 3rd resistor 43 is 10K Ω, but the present invention is not with this
It is limited, the specific resistance value of resistance number and corresponding resistor that first resistor unit and second resistance unit are specifically arranged can be according to reality
Border needs to be configured;A/D converting unit 5 is used to acquire the voltage at second resistance unit (3rd resistor 43) both ends, and by mould
Quasi- signal is converted to digital signal, isolation communication unit 6 is sent to, preferably, the model ADS1115 of A/D conversion unit 5;
Isolation communication unit 6 is used to the digital signal received carrying out isolation processing, is then sent to micro-control unit 7, simultaneously also
It can ensure that micro-control unit 7 is not influenced by high-pressure section failure, improve the safety coefficient of system, preferably, isolation communication unit
The model ADuM1251ARZ of member 6;Micro-control unit 7 is by judging that real-time digital signal value obtains cathode relay 3
The digital signal value received is specifically compared with the value of setting, the state of cathode relay 3 is judged with this by state
It is whether normal, so the monitoring of the state of cathode relay 3 can be improved the stability and reliability of the circuit system of battery;If
The state of cathode relay 3 is abnormal, and micro-control unit 7 prompts operator by warning device, improves the safety of maintenance personal
Property, help to prevent personnel from accidentally touching equipment and causing casualty accident.Preferably, micro-control unit 7 is designed using AT89S52
Single-chip minimum system.
Preferably, with sample reference b is electrically connected the ground terminal of A/D converting unit 5 and isolation communication unit 6.A/D turns
Unit 5 and isolation communication unit 6 with same sample reference b are changed, can reduce the noise jamming in signal transmission.
Preferably, detection circuit further includes isolated power supply 10, A/D converting unit 5, isolation communication unit 6 and microcontroller list
Member 7 is electrically connected with isolated power supply 10.The power input of A/D converting unit 5, isolation communication unit 6 and micro-control unit 7 is equal
It is connected to isolated power supply 10, can reduce the influence of noise in signal transmission in this way, improve the stability of digital signal.
Preferably, A/D converting unit 5, isolation communication unit 6, micro-control unit 7 are logical by clock communication line and data
Letter line carries out data transmission.Data telecommunication line SDA is bidirectional data line, and clock communication line SCL is clock line, in I2C bus
Data are transmitted, send highest order first, such as: enabling signal being issued by host, SDA is by high level jump between SCL high period
Then low level is sent the data of a byte by host;Data Transfer Done issues stop signal by host, and SDA is in SCL
Being jumped between high period by low level is high level, i.e. the transmission of realization orderly information.
Preferably, positive relay 2 and cathode relay 3 are single-contact relay.Single-contact relay structure compares
Simply, facilitate maintenance personal to repair circuit.
Preferably, detection circuit further includes warning device, and warning device is electrically connected with micro-control unit 7.Warning device is used
In prompt operator or maintenance personal, helps to find that cathode relay 3 is adhered in advance, improve the safety of battery.
Preferably, micro-control unit 7 is electrically connected with cathode relay 3.Micro-control unit 7 can control cathode relay 3
Closing or opening.
Micro-control unit 7 uses single-chip microcontroller or PLC control device.Single-chip microcontroller is using very large scale integration technology handle
Central processor CPU, random access memory ram, read only memory ROM, a variety of I/O mouthfuls and interruption systems with data-handling capacity
The circuits collection such as system, timer/counter, display driver circuit, pulse-width modulation circuit, analog multiplexer and A/D converter
At to the small and perfect microcomputer system constituted on one piece of silicon wafer, it is widely applied in industrial control field;PLC control
Device processed has the characteristics that versatile, easy to use, to adapt to wide, high reliablity, strong antijamming capability, programming simple, because
This, using single-chip microcontroller or PLC control device as micro-control unit 7.
Embodiment 2
As shown in Figure 1 and 2, a kind of detection method that high voltage negative relay is adhered, includes the following steps:
1) A/D converting unit 5 acquires voltage of the electric car in voltage acquisition point a in power process and sample reference between b
Then Uab converts analog signals into digital signal, and be sent to isolation communication unit 6;
2) received signal is carried out isolation processing by isolation communication unit 6, and is sent to micro-control unit 7;
3) according to voltage acquisition point a in power process and sample reference the voltage Uab between b of micro-control unit 7, judges cathode
Whether relay 3 is adhered, if cathode relay 3 is adhered, micro-control unit 7 can send prompt or warning by warning device
To operator or maintenance personal.
The method that cathode relay is adhered is judged in step 3), is included the following steps:
If entire car controller has sent 1 power-on command of battery pack, and Uab > 0, then 3 normally closed of cathode relay is judged;
If entire car controller has sent 1 power off command of battery pack, and Uab=0, then judge that cathode relay 3 normally disconnects;
If entire car controller has sent 1 power off command of battery pack, and Uab > 0, then judge that cathode relay 3 is adhered.
It should be noted that: in detection method of the invention, step 1) voltage acquisition point a and sample reference between b
Voltage Uab be actually the voltage at second resistance unit (i.e. 3rd resistor 43) both ends is sampled, A/D converting unit 5
Voltage Uab is monitored in real time, and is translated into digital signal;Step 2) is isolated communication unit 6 and is suitable for complicated circuit
Between communication isolating, communication efficiency can not only be improved, moreover it is possible to enhance the applicable performance of circuit;Step 3) is due to cathode relay
3 disconnect after can in sample reference b generate Zero potential reference, and one end of second resistance unit (i.e. 3rd resistor 43) with adopt
Sample is connected with reference to ground b, thus sample reference voltage between b and voltage acquisition point a can be used for judging that cathode relay 3 is
It is no to be adhered, increase warning device, operator or maintenance personal can have found that cathode relay 3 is adhered in time, not only improve battery
Service life, moreover it is possible to reduce the probability of safety accident.
It should be noted that the detection circuit that is adhered of high voltage negative relay provided by the above embodiment detection cathode after
When electric appliance is adhered, only the example of the division of the above functional modules, in practical application, can according to need and will be upper
State function distribution by different functional modules, to complete all or part of the functions described above.In addition, above-described embodiment mentions
The detection circuit that the detection method and high voltage negative relay that the high voltage negative relay of confession is adhered are adhered belongs to same technology structure
Think, specific implementation process is detailed in Installation practice, and details are not described herein.
According to the disclosure and teachings of the above specification, those skilled in the art in the invention can also be to above-mentioned embodiment party
Formula is changed and is modified.Therefore, the invention is not limited to above-mentioned specific embodiment, all those skilled in the art exist
Made any conspicuous improvement, replacement or modification all belong to the scope of protection of the present invention on the basis of the present invention.This
Outside, although using some specific terms in this specification, these terms are merely for convenience of description, not to the present invention
Constitute any restrictions.