Summary of the invention
The purpose of the utility model one embodiment is to provide a kind of Power-capacitance hurl-slices switch, and the fling-cut switch of this embodiment utilizes one group of thyristor, cooperates many group main contactors and secondary contactor, controls the switching of many group power capacitors.
The utility model one embodiment provides a kind of power capacitor fling-cut switch, comprise switching circuit and control circuit, described switching circuit comprises: the one group of thyristor that is electrically connected with any two of three-phase electricity, another at least two group electric capacity that are electrically connected with described three-phase electricity, every group of electric capacity connects one group of main contactor and one group of secondary contactor respectively, connects the secondary contactor and described thyristor series connection back and the main contactor parallel connection that is connected this group electric capacity of every group of electric capacity; Described control circuit comprises: microcontroller circuit is used for the monitoring system operation conditions, and produces the clock signal of described switching circuit according to external command; Photoelectricity coupling input circuit is used for the photoelectricity coupling input of outside switching order; Drive circuit connects described microcontroller circuit and described switching circuit, is used for driving according to described clock signal the switching operation of described every group of electric capacity.
Described clock signal comprises: secondary contactor clock signal, main contactor clock signal and thyristor clock signal.
Described drive circuit further comprises: thyristor gating circuit, connect described microcontroller circuit and described thyristor, and be used for controlling the connection and the disconnection of described thyristor according to described thyristor clock signal; Relay drive circuit connects described microcontroller circuit and all main contactors and secondary contactor, is used for controlling being connected and disconnection of every group of main contactor and secondary contactor according to described main contactor clock signal with described secondary contactor clock signal.
Described control circuit also comprises the open-phase protection circuit that connects described microcontroller circuit.Be used to detect three-phase electricity and phase shortage whether occurs, if phase shortage, the microprocessor output of reporting to the police, the electric capacity that excision has dropped into, and forbid that electric capacity drops into again.
Described control circuit also comprises the transistors breakdown testing circuit that connects described microcontroller circuit and described thyristor.Be used for the state of thyristor is monitored, switch occur to be punctured or during not conducting phenomenon at thyristor, the microprocessor output of reporting to the police, and forbid that electric capacity drops into again.
Described thyristor is full control thyristor or half control thyristor.
Described every group of electric capacity is corner connection electric capacity.
The fling-cut switch of the utility model embodiment adopts one group of thyristor to cooperate many group main contactors and secondary contactor to control the switching of many group power capacitors.In the process of electric capacity connection and disconnection, have the characteristics of thuristor throw-in and throw-off no-flashy-flow, no switching overvoltage; Have contactor during normal the connection and do not have power consumption, athermic characteristics.One group of thyristor of present embodiment fling-cut switch can be controlled multiple unit capacitor, makes the whole switching capacity of this fling-cut switch big, has effectively reduced the relative volume of switch, improves the utilance of thyristor, has reduced the switch cost.
Embodiment
Below in conjunction with accompanying drawing embodiment of the present utility model is elaborated.
Fig. 2 is the overall structure figure of present embodiment fling-cut switch.As shown in the figure, the power capacitor fling-cut switch of present embodiment comprises switching circuit 20 and control circuit 21.Control circuit 21 comprises photoelectricity coupling input circuit 211, drive circuit 212 and microcontroller circuit 213.Photoelectricity coupling input circuit 211 is used for the photoelectricity coupling input of outside switching order; Microcontroller circuit 213 is used for the monitoring system operation conditions, and produces the clock signal of described switching circuit according to external command; Drive circuit 212 connects described microcontroller circuit and described switching circuit, is used for driving according to described clock signal the switching operation of 20 every groups of electric capacity of switching circuit.
Fig. 3 is the structure chart of present embodiment drive circuit.As shown in the figure, in a preferred embodiment, switching drive circuit 212 further comprises thyristor gating circuit 301 and relay drive circuit 302, thyristor gating circuit 301 connects microcontroller circuit 213 and thyristor 303, and relay drive circuit 302 connects microcontroller circuit 213 and main contactor 304 and secondary contactor 305.
Microcontroller circuit 213 is judged according to external command and is carried out operation of electric capacity input or electric capacity excision operation, and be respectively and drop into operation and produce corresponding clock signal with the excision operation, these clock signals comprise that being used to control thyristor connects with the thyristor clock signal that disconnects, is used to control main contactor and is connected with the main contactor clock signal of disconnection and is used to control that secondary contactor is connected and the secondary contactor clock signal of disconnection.Thyristor gating circuit 301 is according to the connection and the disconnection of described thyristor clock signal control thyristor 303, and thyristor gating circuit 301 can adopt pulse transformer and related circuit thereof to realize.Relay drive circuit 302 is according to being connected and disconnection of main contactor clock signal and secondary contactor clock signal control main contactor 304 and secondary contactor 305.
Fig. 4 is the detailed structure view of present embodiment control circuit.As shown in the figure, in a kind of preferred implementation, microcontroller circuit 213 usefulness single-chip microcomputers 401 realize that Fig. 4 has increased open-phase protection circuit 402 and the transistors breakdown testing circuit 403 that links to each other with single-chip microcomputer 401 on the basis of Fig. 3.Photoelectricity coupling input circuit 211 through behind the photoelectrical coupler, is sent into outside switching order in the single-chip microcomputer.Open-phase protection circuit 402 uses transformer to extract the synchronizing signal of three-phase electricity, sends in the single-chip microcomputer, and any one electric mutually disappearance, single-chip microcomputer can both detect, the output of reporting to the police, the electric capacity that excision has dropped into, and forbid that electric capacity drops into again.Transistors breakdown testing circuit 403 is got the level signal of thyristor anode and cathode, sends into single-chip microcomputer after photoelectricity is isolated and detects, if the fault of detecting, single-chip microcomputer is reported to the police and exported, and forbids that electric capacity drops into again.
Fig. 5 is the detailed circuit diagram of present embodiment switching circuit 20.This switching circuit comprises: one group of thyristor T1, T2, organize main contactor K1~Kn more, and organize secondary contactor L1~Ln more, organize capacitor C 1~Cn more, and three-phase electricity IN1, IN2 and IN3.Thyristor T1 and T2 are connected any two-phase electricity IN1 and the IN2 of three-phase electricity respectively, and remaining one mutually electric IN3 connects many group capacitor C 1~Cn.Every group of electric capacity connects one group of main contactor and one group of secondary contactor respectively, connects the secondary contactor and thyristor T1, T2 series connection back and the main contactor parallel connection that is connected this group electric capacity of every group of electric capacity.Below describe the structure of this circuit in detail.
As shown in Figure 5, IN1, IN2, IN3 connect three-phase electricity, and T1 is connected with the main contact 1 of main contactor K1~Kn with the end that IN1 links to each other, and the other end of T1 is connected with the main contact 1 of secondary contactor L1~Ln.T2 is connected with the main contact 3 of main contactor K1~Kn with the end that IN2 links to each other, and the other end is connected with the main contact 3 of secondary contactor L1~Ln.The main contact 2 of main contactor K1~Kn links to each other with main contact 4 with the main contact 2 of secondary contactor L1~Ln respectively with main contact 4.Every group of electric capacity connects one group of main contactor and one group of secondary contactor respectively, the OUT11-OUTn1 of capacitor C1-Cn connects the main contact 2 of main contactor K1-Kn and the main contact 2 of secondary contactor L1-Ln respectively, and OUT12-OUTn2 connects the main contact 4 of main contactor K1-Kn and the main contact 4 of secondary contactor L1-Ln respectively.Thyristor T1, T2 can select full control or half control thyristor by demand, also can adopt each mutually several thyristor series connection to use according to the voltage needs.
Fig. 6 describes present embodiment capacitor switching principle for a kind of switching command timing figure that present embodiment adopted in detail below in conjunction with Fig. 4, Fig. 5 and Fig. 6.The high level of present embodiment external command represents to throw electric capacity, and the low level of external command represents to cut electric capacity, has an external command to control the switching operation of this group electric capacity respectively for each group electric capacity.External command enters single-chip microcomputer 401 by photoelectricity coupling input circuit 211, single-chip microcomputer 401 is analyzed this order for throwing the electric capacity order or cutting the electric capacity order, produces the order of secondary contactor switching according to different orders to control being connected and disconnection of every group of main contactor and secondary contactor with the order of main contactor switching and by relay drive circuit 302; Produce the thuristor throw-in and throw-off order simultaneously and control the connection and the disconnection of thyristor 303 by thyristor gating circuit 301.
With the 2nd group of electric capacity is example, when second group of electric capacity need be when off-state changes to on-state, according to the sequential of Fig. 6 as can be known, at first secondary contactor 2 adhesives, thyristor conducting then, then main contactor 2 adhesives, thyristor disconnects then, and last secondary contactor 2 disconnects.Second group of electric capacity input action this moment (promptly from being disconnected to the action of connection) finished.Above process adopts the series arm of thyristor and secondary contactor 2 to connect earlier, main contactor 2 branch roads are connected then, disconnect the series arm of thyristor and secondary contactor 2 at last, the on-state that keeps main contactor 2, thereby realized that second group capacitor is from being disconnected to the process of connection, owing to adopt thyristor to connect and disconnection, effectively avoided the generation of shoving.
In like manner, when second group of electric capacity need be when on-state changes to off-state, according to the sequential of Fig. 6 as can be known, and at first secondary contactor 2 adhesives, thyristor conducting then, then main contactor 2 disconnects, and thyristor disconnects then, and last secondary contactor disconnects.Above process adopts the series arm of thyristor and secondary contactor 2 to connect earlier, main contactor 2 branch roads disconnect then, disconnect the series arm of thyristor and secondary contactor 2 at last, thereby realized that second group capacitor is from being switched to the process of disconnection, owing to adopt thyristor to connect and disconnection, effectively avoided the generation of shoving.
When first and second groups of electric capacity all need when on-state changes to off-state, present embodiment disconnects first group of electric capacity earlier and disconnects second group of electric capacity then.Concrete operating process according to the time order and function order is: secondary contactor 1 adhesive->the thyristor conducting->main contactor 1 disconnection->the thyristor disconnection->secondary contactor 1 disconnection->secondary contactor 2 adhesives->the thyristor conducting->main contactor 2 disconnections->the thyristor disconnection->secondary contactor 2 disconnections.
The advantage of the existing thuristor throw-in and throw-off no-flashy-flow of intelligent multichannel composite switching switch of the present utility model, no switching overvoltage has contactor not have power consumption, athermic advantage again.The structure of its switching circuit makes one group of thyristor be used for the access and the excision control of multiple unit capacitor, has solved prior art and has controlled in the combination switch of single group capacitor, and the thyristor utilance is low, switch cost height, little, the bulky defective of capacity.
Above embodiment only is used to illustrate the utility model, but not is used to limit the utility model.