Alternating-current charging stake output state detection circuitry
Technical Field
The utility model relates to a detection circuitry technical field specifically is an alternating-current charging stake output state detection circuitry.
Background
In early alternating current charging piles, alternating current output contactors are generally adopted as alternating current output control. The alternating current output contactor is adopted as an output, so that the heating value and the temperature rise are small, but the occupied space is large, the cost is high, the driving current is large, the energy consumption is high, the efficiency is low, more wiring is required, and the integration is not facilitated. The cost is even more expensive if a contactor with output feedback contacts is used. However, for safety reasons, it is necessary to use a contactor with output feedback contacts. In addition, because of the huge size and need external cable to realize control and feedback, be unfavorable for the miniaturization and the integration of product, process such as production wiring also causes certain influence to production efficiency and product stability to many.
With the development of solder-type (i.e., relay soldered to a circuit board) relay technology, more and more ac charging posts nowadays use relays as output control of ac power. The relay is light in size, low in cost and low in driving current, is directly welded on a circuit board without extra wiring, and is a qualitative leap in the aspects of miniaturization and integration of products, cost and efficiency. However, due to the limitations of the technology, requirements, application occasions and the like of the welded plate type relay, the welded plate type relay generally does not have an output feedback contact, so that the output state cannot be acquired, the output state cannot be known, the judgment result is unknown whether the output state is good or bad, and great potential safety hazards exist. However, because this kind of relay does not have the output feedback contact almost, in order to obtain actual output state to get rid of the potential safety hazard, provide safer guarantee, need fill electric pile producer and additionally increase output state feedback circuit.
At present, most charging pile manufacturers adopting relays do not additionally increase an output feedback circuit, so that potential safety hazards exist; and manufacturers continue to use the complex circuit to realize output state acquisition, and the circuit still has the defects of large volume, high cost, high energy consumption and the like.
SUMMERY OF THE UTILITY MODEL
The utility model provides an alternating-current charging stake output state detection circuitry has small, advantage with low costs, can improve the security of filling electric pile.
In order to solve the technical problem, the present application provides the following technical solutions:
an alternating current charging pile output state detection circuit includes: diode and opto-coupler, two output of electric pile are filled in the connection of diode both ends, the negative pole of diode is connected with the emitting diode's of opto-coupler anodal, the positive pole of diode is connected with the emitting diode's of opto-coupler negative pole, the photic ware of opto-coupler connects signal output circuit.
In the technical scheme of the utility model, the diode both ends connect the output of electric pile, when the electric pile output is normal, the diode can bear reverse voltage in the half cycle of alternating current, is in the off state, when its forward voltage drop that loads at the emitting diode of opto-coupler is greater than the turn-on voltage, the opto-coupler switches on, and then its photic ware passes through output circuit and exports corresponding signal; and when an output or two outputs of filling electric pile do not have the output, the diode does not switch on, the opto-coupler does not switch on, the photic ware of opto-coupler keeps its original state unchangeable, consequently, control device such as output circuit connection singlechip, the control device just can judge the output state of filling electric pile at present by the output state of photic ware, realize the charged state and detect, this scheme only has several components, and the charging pile has simple structure, low cost, small, do benefit to the integration, can improve and fill electric pile security, high efficiency, the energy consumption is low, do benefit to advantages such as production. And a clamping circuit is formed between the diode and the emitting diode of the optocoupler, so that the problem of diode normal phase voltage breakdown can be avoided, and the damage of elements can be avoided.
Furthermore, the light receiver is a photosensitive semiconductor tube, a collector of the photosensitive semiconductor tube is connected with a power supply, and an emitter of the photosensitive semiconductor tube is a signal output end.
When the emitting diode of the optical coupler emits light, the photosensitive semiconductor tube is conducted, the emitting electrode of the photosensitive semiconductor tube outputs high level, and otherwise, the emitting electrode outputs low level.
And the current-limiting resistor is connected between the diode and the output end of the charging pile in series.
The current flowing through the optocoupler is limited through the current limiting resistor, and damage caused by overlarge current is avoided.
Further, the current limiting resistor is provided in plurality. The current limiting resistors together limit the current and protect subsequent elements.
Further, the signal output circuit includes a filter circuit for filtering the output signal.
The signal is filtered through the filter circuit, and noise is reduced.
Further, the filter circuit is an RC filter circuit. And filtering is realized through an RC filter circuit.
The charging pile further comprises a controller, the controller is connected with the output end of the output circuit, and the controller is used for judging the output state of the charging pile according to the level of the output end. Whether the relay part of the current charging pile breaks down or not is judged through the controller.
The wireless communication module is electrically connected with the controller, and the controller is used for sending the detection result to the server through the wireless communication module. And the remote supervision is convenient.
And the controller is used for controlling the display module to display the detection result. And the maintenance personnel can conveniently check the detection result.
Further, the alarm device also comprises an alarm module, and the controller is also used for controlling the on-off of the alarm module according to the signal of the output circuit. And alarming in time after the fault is detected.
Drawings
Fig. 1 is a circuit diagram of an output control circuit of a conventional ac charging pile;
fig. 2 is a circuit diagram in the embodiment of the output state detection circuit of the ac charging pile.
Detailed Description
The following is further detailed by way of specific embodiments:
example one
The output state detection circuit of the alternating current charging pile of the embodiment is applied to the charging pile, as shown in fig. 1, the charging pile of the embodiment uses a welding plate type relay to replace a traditional alternating current contactor, and the relay basically does not have an output feedback contact. In fig. 1, K _ Relay1_ Ctrl and K _ Relay2_ Ctrl are connected to an IO pin of a single chip microcomputer, and the single chip microcomputer controls simultaneous pull-in or simultaneous disconnection of relays K1 and K2 through the two pins, so that J3 and J5 are powered on or powered off, and charging control of a charging pile is achieved.
An output state detection circuit of an alternating current charging pile in this embodiment is shown in fig. 2, and includes a current-limiting resistor, a diode D15, an optical coupler U9 and an output circuit, where two ends of a diode D15 are connected to output terminals AC _ L _ OUT and AC _ N _ OUT of the charging pile, in this embodiment, a negative electrode of a diode D15 is connected to AC _ L _ OUT, a positive electrode of the diode is connected to AC _ N _ OUT, the current-limiting resistor includes a resistor R33, a resistor R34, a resistor R35 and a resistor R36, the current-limiting resistors are all connected in series between a negative electrode of a diode D15 and the output terminal AC _ L _ OUT of the charging pile, a negative electrode of a diode D15 is connected to a positive electrode of an emitting diode of an optical coupler U9 (i.e., pin No. 1 of the optical coupler U9), a positive electrode of the diode D15 is connected to a negative electrode of an emitting diode of the optical coupler U9. The output circuit in this embodiment includes a filter circuit, the light receiver is a photosensitive transistor, the collector of the photosensitive transistor (i.e. pin No. 4 of optocoupler U9) is connected to the power supply, the emitter of the photosensitive transistor (i.e. pin No. 3 of optocoupler U9) is a signal output end, the filter circuit is an RC filter circuit, including resistance R37 and electric capacity C37 all connected with pin No. 3 of optocoupler U9, this output end is connected to signal input end K _ Relay _ Sta of controller, the controller obtains the testing result through reading the state of K _ Relay _ Sta.
When both relays K1, K2 are normally closed, when the alternating current is positive for a half cycle, the current starts from AC _ L _ OUT, passes through R33, R34, R35, R36, U9 (emitting diode 1-2 pin), and returns to AC _ N _ OUT. The diode D15 is subjected to a reverse voltage during the entire process and is in the off state. When the forward voltage drop loaded to the emitting diode (namely the pin 1-2) of the U9 is larger than the conduction voltage of the emitting diode, the optical coupler is conducted, and the K _ Relay _ Sta outputs a high-level signal.
When the alternating current is negative for half a cycle, the current starts from AC _ N _ OUT, goes through D15 (pin 1-2), R36, R35, R34, R33, and returns to AC _ L _ OUT. The whole process U9 led is under reverse voltage and in off state, so K _ Relay _ Sta outputs low level signal.
When one or both of the relays K1 and K2 are turned off, no matter the positive half cycle or the negative half cycle of the alternating current is adopted, a current loop cannot be formed, so that the optical coupler is always in a cut-off state, and K _ Relay _ St always outputs a low-level signal.
And the controller connected with the K _ Relay _ Sta reads the state of the K _ Relay _ Sta and applies a corresponding filtering method to obtain the actual output state of the Relay, and then compares the actual output state of the Relay with the expected output state, so that the quality of the output circuit of the Relay can be judged. For example, if the relay is controlled by the single chip microcomputer to be closed and the detected actual state is open, the abnormality of the relay circuit is indicated. For another example, the state of the relay controlled by the single chip microcomputer is open, and the detected actual state is closed, which also indicates that the relay circuit is abnormal (the relay is stuck). After the single chip microcomputer detects the abnormality of the relay circuit, the charging pile can be marked as unavailable, and operation and maintenance personnel are informed to maintain the charging pile in the future.
Example two
The difference between this embodiment and the first embodiment is that, in this embodiment, the charging pile further includes a controller, and a wireless communication module, a display module, and an alarm module that are all electrically connected to the controller, wherein a signal input pin of the controller is connected to an output terminal of the output circuit, and the controller is configured to determine an output state of the charging pile according to a level of the output terminal. The controller is used for sending the detection result to the server through the wireless communication module. The controller is used for controlling the display module to display the detection result. The controller is also used for controlling the alarm module to be opened and closed according to the signal of the output circuit. Specifically, in this implementation, the controller is the singlechip, preferably STM32H7 series high performance singlechip, display module adopts 4 inches OLED display screen, the alarm module includes warning light and bee calling organ, wireless communication module adopts 4G network communication module, the output of controller is relay K1 still, K2's control end, in this embodiment, the controller judges whether the electric pile has the trouble through judging output circuit's level and K1, whether K2 output level matches, in other embodiments of this application, judge that partial function also can be realized by hardware such as NAND gate.
EXAMPLE III
The embodiment is different from the second embodiment in that, in this embodiment, the charging pile further includes a delay module, the controller controls the delay module to start before controlling the alarm module to alarm, the controller controls the alarm module to alarm after the delay of the delay module is finished, and in the delay process of the delay module, the controller receives and detects that the output state of the charging pile is normal and then controls the delay module to close. In this embodiment, the delay module adopts the 555 chip as the delay circuit of core, and again in other embodiments of this application, also can adopt the built-in timer of singlechip, and the preferred 1 second of delay time avoids the device to produce the false positive through setting up the delay module, improves detection accuracy.
The above are only embodiments of the present invention, and the present invention is not limited to the field related to this embodiment, and the common general knowledge of the known specific structures and characteristics in the scheme is not described too much, and those skilled in the art know the common technical knowledge in the technical field of the present invention before the application date or the priority date, can know all the prior art in this field, and have the ability to apply the conventional experimental means before this date, and those skilled in the art can combine their own ability to perfect and implement the scheme, and some typical known structures or known methods should not become the obstacles for those skilled in the art to implement the present application. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several modifications and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.