A kind of method for the discharge of power electronic equipment bus capacitor
Technical field
The present invention relates to a kind of charging method, more particularly, relate to a kind of method, guarantee that the power electronic equipment bus capacitor satisfies the safety requirement of discharge for the discharge of power electronic equipment bus capacitor.
Background technology
Along with the fast development of industry, the large-scale power electronic equipment in the application of every profession and trade more and more widely, the power grade and the power density of power electronic equipment are increasingly high, require also more and more stricter to the safety of power electronic equipment.IEC61800-5-1 regulation, behind the dump, any residual voltage of power electronic equipment is higher than the exposed conductive part of 60V, all should within 5 minutes, discharge into 60V or below the 60V.Above-mentioned safety requires to adopt corresponding discharge circuit to satisfy.
For generating equipment, bus capacitor voltage is the voltage of generating equipment system, therefore, the bus capacitor of generating equipment is discharged, and can make generating equipment satisfy above-mentioned safety requirement.
The bus capacitor discharge of existing large-scale power electronic equipment mainly is to be employed in parallelly connected power resistor between the bus capacitor both positive and negative polarity.Behind the system-down, the energy on the bus capacitor drops to below the voltage of safety regulation bus capacitor voltage through the power resistor consumption of parallel connection gradually.
There is following problem in above-mentioned existing discharge circuit:
1, power resistor also is connected between the positive and negative busbar simultaneously, when system's operate as normal, and power
The resistance loss is bigger, and heating is serious, causes big system energy loss;
2, along with the continuous increase of bus capacitor capacity, the bus capacitor voltage magnitude improves constantly, in order to satisfy the safety requirement; The resistance of power resistor is more and more littler; Make the electric current of the power resistor of flowing through increasing, cause system power dissipation increasing, simultaneously; For satisfying resistance volume restrictive condition, discharge time and power consumption condition, the power resistor design more and more difficult that becomes;
3, power resistor becomes one of machine system fixedly thermal source, has increased the heat load of machine system, has increased burden for the heat dissipation design of machine system.
Summary of the invention
The technical problem that the present invention will solve is; A kind of method for the discharge of power electronic equipment bus capacitor is provided, overcomes the system power that the discharge circuit power resistor brings in the prior art and lose greatly, increase defectives such as system radiating load and power resistor difficult design.
The technical solution adopted for the present invention to solve the technical problems is: a kind of method for the discharge of power electronic equipment bus capacitor is provided; Realize based on following circuit structure; Net side converter, bus capacitor and pusher side current transformer that this circuit structure comprises controller, crowbar circuit and is linked in sequence; This controller is netted side converter and pusher side current transformer control connection with this respectively; This crowbar circuit is connected said pusher side current transformer side or is connected between said net side converter and the pusher side current transformer, and said crowbar circuit comprises interconnective internal drive circuits, switching circuit and power consumption resistance; It is characterized in that:
When said crowbar circuit was connected said pusher side current transformer side, said charging method comprised the steps:
SA1, said controller detect net side converter state, pusher side current transformer state, bus capacitor voltage and have or not starting-up signal; Be in stopped status, bus capacitor voltage greater than safe voltage and when not having starting-up signal when said controller detects net side converter and pusher side current transformer, this controller sends drive signal to said pusher side current transformer makes this pusher side current transformer be in inverter mode; This controller sends drive signal to the internal drive circuits of said crowbar circuit, makes the switching circuit action of crowbar circuit, the resistance that will consume energy incision;
SA2, said controller detect bus capacitor voltage; When detecting bus capacitor voltage, this controller is less than or equal to safe voltage; This controller stops to send to the drive signal of said pusher side current transformer and gives the drive signal of the internal drive circuits of said crowbar circuit, makes this pusher side current transformer finish inverter mode and this crowbar circuit is quit work;
When said crowbar circuit was connected between said net side converter and the pusher side current transformer, said charging method comprised the steps:
SB1, said controller detect net side converter state, pusher side current transformer state, bus capacitor voltage and have or not starting-up signal; When detecting net side converter and pusher side current transformer, said controller is in stopped status, bus capacitor voltage greater than safe voltage and when not having starting-up signal; This controller sends drive signal to the internal drive circuits of said crowbar circuit; Make the switching circuit action of crowbar circuit, the resistance that will consume energy incision;
SB2, said controller detect bus capacitor voltage, are less than or equal to safe voltage when this controller detects bus capacitor voltage, and this controller stops to send the drive signal to the internal drive circuits of said crowbar circuit, and this crowbar circuit is quit work.
In the method for the discharge of power electronic equipment bus capacitor of the present invention; When said crowbar circuit is connected said pusher side current transformer side; In said step SA1; Comprise that said controller writes down said crowbar circuit and changes operating state time T 1 constantly into by halted state, in said step SA2, comprise that said controller writes down said crowbar circuit and changes halted state time T 2 constantly into by operating state; Also comprise step SA3, at step SA3, said controller calculate T2-T1 obtain discharge time and the output of bus capacitor should discharge time;
Or when said crowbar circuit is connected between said net side converter and the pusher side current transformer; In said step SB1; Comprise that said controller writes down said crowbar circuit and changes operating state time T 3 constantly into by halted state; In said step SB2, comprise that said controller writes down said crowbar circuit and changes halted state time T 4 constantly into by operating state; Also comprise step SB3, at step SB3, said controller calculating T4-T3 obtains the discharge time of bus capacitor and exports should discharge time.
The method for the discharge of power electronic equipment bus capacitor of embodiment of the present invention compares with prior art, and its beneficial effect is:
1. the crowbar circuit that utilizes power electronic equipment to carry carries out the bus capacitor discharge, and discharge can be accomplished in the hundreds of millisecond, and discharge rapidly; Satisfy the requirement of IEC61800-5-1 safety; The power electronic equipment circuit need not be provided with special-purpose discharge circuit simultaneously, and cost is low, space province;
2. crowbar circuit can not bring extra heat load to machine system because of continuing consumption heating only at the system-down snap action, and is more favourable to the complete machine heat dissipation design;
3. implementing only needs the built-in corresponding Control Software of system controller is got final product, succinct convenient.
Description of drawings
To combine accompanying drawing and embodiment that the present invention is described further below, in the accompanying drawing:
Fig. 1 is that the present invention is the circuit diagram among the method embodiment one of power electronic equipment bus capacitor discharge.
Fig. 2 is the flow chart of the present invention for the method embodiment one of power electronic equipment bus capacitor discharge.
Fig. 3 is that the present invention is the circuit diagram among the method embodiment two of power electronic equipment bus capacitor discharge.
Fig. 4 is the flow chart of the present invention for the method embodiment two of power electronic equipment bus capacitor discharge.
Fig. 5 is the enlarged drawing of the present invention for crowbar circuit in the method for power electronic equipment bus capacitor discharge.
Embodiment
Embodiment one
Like Fig. 1, Fig. 2, shown in Figure 5, power electronic equipment bus capacitor charging method of the present invention is realized based on following circuit structure: circuit structure comprises controller 70, crowbar circuit 30 and the net side converter 60 that is linked in sequence, bus capacitor 50 and pusher side current transformer 40.
Controller 70 respectively with net side converter 60 and pusher side current transformer 40 control connections.
Crowbar circuit 30 is connected pusher side current transformer 40 sides, comprises the internal drive circuits 120 that connects successively, switching circuit 100 and power consumption resistance 90.Drive circuit 120 and controller 70 control connections.
The bus capacitor charging method comprises the steps:
The first step, controller 70 detect state, the pusher side current transformer 40 of net side converters 60 state, bus capacitor 50 voltage and have or not starting-up signal; When controller 70 detects voltage that net side converter 60 and pusher side current transformer 40 be in stopped status, bus capacitor 50 greater than safe voltage and when not detecting starting-up signal; Controller 70 sends drive signal to pusher side current transformer 40, makes pusher side current transformer 40 be in inverter mode; Controller 70 sends drive signal to the internal drive circuits 120 of crowbar circuit 30, makes switching circuit 100 actions of crowbar circuit 30, resistance 90 incisions of will consuming energy; At this moment, bus capacitor 50 is through pusher side current transformer 40 and crowbar circuit 30 formation loops, and the energy of bus capacitor 50 obtains rapid release through power consumption resistance 90.
Second step, controller 70 detect bus capacitor voltage; When detecting the bus capacitor voltages, controller 70 drops to safe voltage (this safe voltage is built in the controller 70) or safe voltage when following; Controller 70 stops to send to the drive signal of pusher side current transformer 40 and gives the drive signal of the internal drive circuits 120 of crowbar circuit 30, makes that pusher side current transformer 40 finishes inverter modes, crowbar circuit 30 quits work.This moment, bus capacitor 50 discharge processes finished.
In other embodiments, operating personnel grasp the discharge time of bus capacitor for ease, and power electronic equipment bus capacitor charging method of the present invention also comprises:
In the above-mentioned first step, comprise that controller 70 record crowbar circuits 30 change operating state time T 1 constantly into by halted state, in above-mentioned second step, comprise that controller 70 record crowbar circuits 30 change halted state time T 2 constantly into by operating state; Comprise that step the three goes on foot, controller 70 calculating T2-T1 obtain bus capacitor discharge time and output should discharge times.The way of output includes but not limited to export, export or with the signalling formula (as sending the modes such as note of carrying discharge time) of carrying information discharge time output etc. with the display message mode with the voice messaging mode.
Embodiment two
Like Fig. 3, Fig. 4, shown in Figure 5, power electronic equipment bus capacitor charging method of the present invention is realized based on following circuit structure: circuit structure comprises controller 70, crowbar circuit 30 and the net side converter 60 that is linked in sequence, bus capacitor 50 and pusher side current transformer 40.
Controller 70 respectively with net side converter 60 and pusher side current transformer 40 control connections.
Crowbar circuit 30 is connected between net side converter 60 and the pusher side current transformer 40, comprises the internal drive circuits 120 that connects successively, switching circuit 100 and power consumption resistance 90.Drive circuit 120 and controller 70 control connections.
The bus capacitor charging method comprises the steps:
The first step, controller 70 detect state, the pusher side current transformer 40 of net side converters 60 state, bus capacitor 50 voltage and have or not starting-up signal; When controller 70 detects voltage that net side converter 60 and pusher side current transformer 40 be in stopped status, bus capacitor 50 greater than safe voltage and when not detecting starting-up signal; Controller 70 sends drive signal to the internal drive circuits 120 of crowbar circuit 30; Make switching circuit 100 actions of crowbar circuit 30, resistance 90 incisions of will consuming energy; At this moment, bus capacitor 50 is through crowbar circuit 30 formation loops, and the energy of bus capacitor 50 obtains rapid release through power consumption resistance 90.
Second step, controller 70 detect bus capacitor voltage; When detecting the bus capacitor voltages, controller 70 drops to safe voltage (this safe voltage is built in the controller 70) or safe voltage when following; Controller 70 stops to send the drive signal to the internal drive circuits 120 of crowbar circuit 30, and crowbar circuit 30 is quit work.This moment, bus capacitor 50 discharge processes finished.
In other embodiments, operating personnel grasp the discharge time of bus capacitor for ease, and power electronic equipment bus capacitor charging method of the present invention also comprises:
In the above-mentioned first step, comprise that controller 70 record crowbar circuits 30 change operating state time T 3 constantly into by halted state, in above-mentioned second step, comprise that controller 70 record crowbar circuits 30 change halted state time T 4 constantly into by operating state; Comprise that step the three goes on foot, controller 70 calculating T4-T3 obtain bus capacitor discharge time and output should discharge times.The way of output includes but not limited to export, export or with the signalling formula (as sending the modes such as note of carrying discharge time) of carrying information discharge time output etc. with the display message mode with the voice messaging mode.