JP5428427B2 - Uninterruptible power supply system - Google Patents

Description

  The present invention comprises two uninterruptible power supply systems consisting of a plurality of uninterruptible power supplies operated in parallel or a single-machine uninterruptible power supply, and either one of the two uninterruptible power supply systems is connected to a corresponding load. The present invention relates to an uninterruptible power supply system including a plurality of switching boards for supplying power.

  FIG. 5 is a circuit configuration diagram showing a conventional example of this type of uninterruptible power supply system, including the configuration of Patent Document 1 below.

  In this figure, 10 is a 1-system power system composed of a commercial power system and private power generation facilities, and 11 to 13 are uninterruptible power supplies (hereinafter referred to as UPS 11 to UPS 13) that form a 1-system uninterruptible power supply. 14 is a 1-system bus board formed by circuit breakers 15 to 17, and the 1-system UPS and 1-system bus board form a 1-system uninterruptible power system. Yes. Similarly, 20 is a two-system power system composed of a commercial power system and private power generation facilities, and 21 to 23 are uninterruptible power supplies forming a two-system uninterruptible power supply (hereinafter referred to as UPS21 to UPS23, and these are generic names) , 24 is a 2-system bus board formed by circuit breakers 25-27, and the 2-system UPS and 2-system bus board form a 2-system uninterruptible power system. . Reference numeral 31 denotes a system control circuit that controls the operation system of the entire uninterruptible power supply system.

  In this 1-system uninterruptible power supply system, each of the UPS 11 to UPS 13 includes a bypass circuit that performs direct power feeding from the 1-system power system 10 and functions to operate in parallel with each other when the circuit breakers 15 to 17 are closed. It has. Similarly, in the 2 system uninterruptible power system, each of the UPS 21 to UPS 23 is provided with a bypass circuit that performs direct power feeding from the 2 system power system 20, and when the circuit breakers 25 to 27 are closed, they are operated in parallel with each other. It has a function to do.

  The high-speed switching panel 40 is formed of thyristor switches 41 and 42 as high-speed switches and a switching command circuit 43, and supplies power to the load A (100) by a command from the system control circuit 31 to the switching command circuit 43. It has a function to perform from the 1 system uninterruptible power system or the 2 system uninterruptible power system. Similarly, the high-speed switching board 50 is formed of thyristor switches 51 and 52 as high-speed switches and a switching command circuit 53, and supplies power to the load B (200) by a command from the system control circuit 31 to the switching command circuit 53. It has a function to perform from the 1 system uninterruptible power system or the 2 system uninterruptible power system. Similarly, the high-speed switching board 60 is formed of thyristor switches 61 and 62 as high-speed switches and a switching command circuit 43, and supplies power to the load C (300) by a command from the system control circuit 31 to the switching command circuit 63. It has a function to perform from the 1 system uninterruptible power system or the 2 system uninterruptible power system.

  In any of the high-speed switching boards 40, 50, 60, for example, the power supply switching of the load corresponding to the system 2 uninterruptible power system from the system 1 uninterruptible power system can be performed at high speed and shock using the thyristor switch shown in the figure. Therefore, the output voltages of the uninterruptible power supply systems are phase-synchronized with each other.

For the above, each component in the uninterruptible power supply system shown in FIG. 5 is formed using a well-known technique.
JP 2007-306643 A

  In this type of uninterruptible power supply system, for example, in order to perform maintenance of each uninterruptible power supply without stopping power supply to each load, for example, one system It is required to switch the power supply of the load corresponding to the uninterruptible power system 2 from the uninterruptible power system.

  However, in the uninterruptible power supply system shown in FIG. 5, the high-speed switching panels 40, 50, 60 do not have a function of grasping the total current consumption values of the loads 100, 200, 300. Thus, while confirming the total current consumption value, for example, the power supply path of the load corresponding to the system 2 uninterruptible power system is switched from the system 1 uninterruptible power system. As a result, the uninterruptible power system after switching There was an overload condition. Further, in order to determine whether or not this overload state can be avoided, an operator who is familiar with this uninterruptible power supply system needs to respond.

  An object of the present invention is to provide an uninterruptible power supply system that solves the above problems.

The inventions of this, an uninterruptible power supply a plurality of parallel operation or single machine consisting uninterruptible power operating an uninterruptible power supply system 2 Kumisonae, any corresponding load from one of the two pairs of uninterruptible power supply system, In the uninterruptible power supply system comprising a plurality of switching boards for supplying power to each other, the output voltages of the uninterruptible power supply systems being phase-synchronized with each other,
Wherein the respective switching換盤, or when switching the power supply path from one of the uninterruptible power supply system to the other load corresponding to the uninterruptible power supply system, an uninterruptible power supply system of the other after the switching from falling into an overload state A switching determination means for determining whether or not in advance,
The switching determination means is
Estimated value calculation means for calculating the load current estimated value after switching based on the total value of the load current before switching in the uninterruptible power supply system at the switching destination and the corresponding load current value at the switching source;
The load current estimated value is formed from a comparison calculation means for performing a comparison calculation between the current rated output current value of the uninterruptible power supply system to be switched to,
It is characterized by that.

  According to the present invention, since the uninterruptible power supply system is provided with the switching determination function, the uninterruptible power supply system falls into an overload state not only at the time of maintenance but also when switching the power supply path to the load at the normal time. Whether or not can be automatically determined in advance, and therefore, an uninterruptible power supply system with high operational reliability can be provided.

  FIG. 1 is a circuit configuration diagram of an uninterruptible power supply system showing an embodiment of the present invention. Components having the same functions as those in the conventional configuration shown in FIG. 5 are denoted by the same reference numerals.

  That is, in FIG. 1, the UPS 11 a to UPS 13 a forming the 1-system UPS can send a “power supply” signal when supplying power to the load in addition to the functions of the conventional UPS 11 to UPS 13. In addition to the circuit breakers 15 to 17, a relay circuit 19 that relays signals is added to the 1-system bus board 18. Similarly, the UPS 21a to UPS 23a forming the 2-system UPS can send a “power supply” signal when supplying power to the load in addition to the functions of the conventional UPS 21 to UPS 23. In addition to the circuit breakers 25 to 27, a relay circuit 29 having a function of relaying “signal 1 to signal 8” described later is added to the 2-system bus board 28. Reference numeral 32 denotes a system control circuit that controls the operation system of the entire uninterruptible power supply system. The UPS 11a to UPS 13a and the UPS 21 to UPS 23 are all UPS having the same specifications and the same capacity, and the output voltages of the UPSs are phase-synchronized with each other. In the figure, the thyristor switches 41, 42, 51, 52, 61, 62 are shown as an example of the high-speed switch. However, the high-speed switch may be a hybrid in which a circuit breaker is connected in parallel with the thyristor, or as an IGBT. Also good.

  Further, the high-speed switching board 44 is formed of thyristor switches 41 and 42, CTs 45 and 47 such as current transformers for detecting current, and switching control circuits 46 and 48, and supplies power to the load A (100) to the system control circuit. 32 has a function of a high-speed switch for performing the operation from the 1-system uninterruptible power supply system or the 2-system uninterruptible power supply system according to a command from 32 to the switching control circuit 46 or the switching control circuit 48. Similarly, the high-speed switching board 54 is formed of thyristor switches 51 and 52, CTs 55 and 57 such as current transformers for detecting a current, and switching control circuits 56 and 58, and power supply to the load B (200) is controlled by the system. According to a command from the circuit 32 to the switching control circuit 56 or the switching control circuit 58, it has a function of a high-speed switch for performing from the 1-system uninterruptible power system or the 2-system uninterruptible power system. Similarly, the high-speed switching board 64 is formed of thyristor switches 61 and 62, CTs 65 and 67 such as current transformers for detecting current, and switching control circuits 66 and 68, and supplies power to the load C (300) for system control. According to a command from the circuit 32 to the switching control circuit 66 or the switching control circuit 68, it has a function of a high-speed switch for performing from the 1-system uninterruptible power supply system or the 2-system uninterruptible power supply system.

  FIG. 2 is a detailed circuit configuration diagram relating to the relay circuit 19 and the switching control circuits 46, 56, 66 on the system 1 uninterruptible power system side of the uninterruptible power system shown in FIG.

  In this relay circuit 19, “signal 1” is active when the UPS 11a is supplying power, “signal 2” is active when the UPS 12a is supplying power, and “signal 3” is supplied by the UPS 13a. Sometimes it becomes active. "Signal 4 and signal 5" are sent from the switching control circuits 46, 56 and 66, respectively, and a current based on the current flowing from the 1-system uninterruptible power system flows through the loads A to C. Furthermore, “signal 6” becomes active when power is being supplied to the load A from the 1-system uninterruptible power supply system via the switching control circuit 46. Similarly, “signal 7” becomes active when power is being supplied to the load B from the 1-system uninterruptible power supply system via the switching control circuit 56. Similarly, “signal 8” becomes active when power is being supplied to the load C from the 1-system uninterruptible power supply system via the switching control circuit 66. Note that “signal 9” is a switching control circuit 48, 58 of the 2-system uninterruptible power system in the same high-speed switching panel 44, 54, 64 from the switching control circuit 46, 56, 66 of the 1-system uninterruptible power system. , 68, and a current based on a current flowing from the uninterruptible power supply system 2 flows through loads A to C.

  Note that the relay circuit 29 on the second uninterruptible power supply system side has the same circuit configuration as that of FIG.

  FIG. 3 is a detailed circuit configuration diagram relating to the switching control circuits 46, 48, 56, 58, 66 and 68 shown in FIG.

  In this figure, reference numeral 71 denotes an auxiliary CT that inputs a secondary current of any one of CTs 45, 47, 55, 57, 65, and 67 installed in the high-speed switching boards 44, 54, and 64. The secondary side of the auxiliary CT 71 is connected to one end of each of the switches 72, 73, 74 and a diode circuit 75 for preventing the secondary side from being released. The other end of the switch 72 is connected to “signals 4 and 5” of the same uninterruptible power system. The other end of the switch 73 is connected to a switch 73 of another switching control circuit of the same high-speed switching panel by “signal 9”.

  Further, the other end of the switch 74 is connected to the primary side of the auxiliary CT 78 via the shunt resistors 76 and 77. The secondary side of the auxiliary CT 78 is connected to a current-voltage conversion circuit including a resistor 79 and an operational amplifier element 80 shown in the figure. That is, the current-voltage conversion circuit converts the AC voltage into an AC voltage proportional to the primary current of the auxiliary CT 78. This AC voltage is converted into an effective value by the effective value calculation circuit 81. Therefore, the effective value calculation circuit 81 outputs an effective value proportional to the primary current of the auxiliary CT 78.

  In addition to this switching control circuit, there is also a simulation for calculating the current value when the multiplication calculator 82 and the thyristor switch in a state where power is not yet supplied are turned on to supply power to the load. A switch 83 for adding one operation unit, an addition calculator 84, a setting unit 85 for presetting the capacity per UPS, a multiplication calculator 86, a comparison element 87, and a thyristor switch are turned on / off. A high-speed switch driving circuit 90 for supplying a signal, a signal output circuit 91 for outputting that power is being supplied to a load, and a thyristor of the same system that is being fed based on signals 6 to 7 of the signal output circuit 91 of the same system A setting circuit 92 for calculating the number of operating switches, a setting unit 93 for calculating the number of operating UPSs of the same system that is being fed based on UPS signals 1 to 3 of the same system, and system control In response to "switching preparation command" from the road 32 and a command circuit 94 for commanding the "feeding capacity confirmation request".

  Note that the circuit configuration shown in FIG. 3 shows one phase of the uninterruptible power supply system. Therefore, when the uninterruptible power supply system has a three-phase output, three sets of components 71 to 87 are required. In this case, a signal obtained by ANDing the output signals of the three sets of comparison elements 87 is output to the high-speed switch drive circuit 90.

  Hereinafter, an operation when, for example, one of the uninterruptible power supply systems switches the power supply of a load corresponding to the other uninterruptible power supply system in any of the high-speed switching panels will be described.

  FIG. 4 shows an example of the uninterruptible power supply system shown in FIG. 1 in which the load A is supplied from the 2-system uninterruptible power system and the loads B and C are supplied from the 1-system uninterruptible power system. FIG. 4 is a partial detailed circuit configuration diagram for explaining an operation when power supply of a load A is switched from a 2-system uninterruptible power supply system that is a switching source to a 1-system uninterruptible power supply system that is a switching destination.

  The operation of the circuit shown in FIG. 4 will be described below with reference to the detailed configuration of the switching control circuit shown in FIG.

  That is, in the high-speed switching board 44, the thyristor switch 42 is turned on by the switching control circuit 48, and the thyristor switch 41 is turned off by the switching control circuit 46. At this time, the switches 72, 73, 74 in the switching control circuit 48 are switched. Are turned on, the switches 72 and 73 in the switching control circuit 46 are turned off, and the switch 74 is turned on. Therefore, the load A is supplied with power from the 2-system uninterruptible power supply system.

  When switching the power supply path of the load A to the 1-system uninterruptible power supply system, a “switching preparation command” is issued from the system control circuit 32 to the command circuit 94 of the switching control circuits 46 and 48, and a “power supply capacity check request” is issued. Become.

  Based on this “power supply capacity confirmation request”, the switches 72 and 73 in the switching control circuit 46 are changed from OFF to ON, and after the ON operation is completed, the switches 72 and 74 in the switching control circuit 48 are turned from ON to OFF. Changes to.

  As a result, the currents of the loads B and C via the “signals 4 and 5” of the relay circuit 19 of the system 1 bus board 18 are routed to the primary path of the shunt resistors 76 and 77 and the auxiliary CT 78 in the switching control circuit 46. And the current obtained by averaging the current based on the current of the load A via the “signal 9” from the switching control circuit 48 are shunted. Therefore, an effective value proportional to the primary current of the auxiliary CT 78, that is, an effective value of the averaged current is output to the effective value calculation circuit 81 of the switching control circuit 46.

  At this time, since the thyristor switch 41 is not turned on, the “signal 6” via the signal output circuit 91 of the switching control circuit 46 is not active, and the setting circuit 92 receives “2” according to “signals 7 and 8”. ”Is output, and the output value of the addition computing unit 84 obtained by adding“ 2 ”and“ 1 ”by the turned on switch 83 based on the“ power supply capacity confirmation request ”is“ 3 ”. An estimated value of the total current consumption of the loads A to C is output as a “load current estimated value” by a multiplication calculator 82 that multiplies “3” by the output value of the effective value calculation circuit 81.

  On the other hand, in the setting circuit 93, for example, when the UPSs 11a to 13a are both in parallel operation and are in the “power supply” state, “3” is output. Since the setter 85 outputs the rated output current value per UPS 11a to UPS13a, the multiplier 86 outputs the current “rated output current value” of the 1-system uninterruptible power supply system. The

  In this setting circuit 93, for example, when the UPS 11 a to UPS 13 a are in the “power supply” state while performing the parallel redundant operation, “2” is output. Since the setter 85 outputs the rated output current value per UPS 11a to UPS13a, the multiplier 86 outputs the current “rated output current value” of the 1-system uninterruptible power supply system. The

  As a result, the comparison element 87 compares the “rated output current value” with the “load current estimated value”, and when “rated output current value” ≧ “load current estimated value”, “switchable” is driven at high speed. This is transmitted to the circuit 90 and the system control circuit 32, and when “rated output current value” <“load current estimated value”, “not switchable” is transmitted to the high-speed switch drive circuit 90 and the system control circuit 32.

  The system control circuit 32 that has received this “switchable” newly transmits a “thyristor switch OFF command” to the switch control circuit 48 and a “thyristor switch ON command” to the switch control circuit 46.

  In the switching control circuit 48 that has received this “thyristor switch OFF command”, the thyristor switch 42 is changed from on to off via the high-speed switch drive circuit 90, and the “switching preparation command” is canceled, and the switching control circuit 48 The switches 72 and 73 are turned off and the switch 74 is turned on, and the state of the “signal 6” of the relay circuit 29 is changed via the signal output circuit 91. On the other hand, in the switching control circuit 46 that has received the “thyristor switch ON command”, the thyristor switch 41 is changed from OFF to ON via the high-speed switch drive circuit 90, and the “switching preparation command” is canceled, so that the switching control circuit The switches 72, 73 and 74 in 46 are all turned on, and the switching operation is completed by changing the “signal 6” of the relay circuit 19 to the active state via the signal output circuit 91.

  Further, in the system control circuit 32 that has received the “non-switchable”, the “switching preparation command” is canceled, and the uninterruptible power supply system continues the previous operation state and transmits this “non-switchable” to the outside. .

  According to the uninterruptible power supply system of the present invention, since the switching control circuits 46, 48, 56, 58, 66, and 68 are provided, not only at the time of maintenance but also at the time of switching the power supply path to the load at the normal time. It is possible to automatically determine in advance whether or not the uninterruptible power supply system will fall into an overload state. Therefore, it is possible to provide an uninterruptible power supply system with high operational reliability such as overload protection. it can.

Circuit configuration diagram of an uninterruptible power supply system showing an embodiment of the present invention Partial detailed circuit configuration diagram of FIG. Partial detailed circuit configuration diagram of FIG. FIG. 1 is a partial detailed circuit diagram illustrating the operation of FIG. Circuit diagram of uninterruptible power supply system showing conventional example

  DESCRIPTION OF SYMBOLS 10 ... 1 system power system, 11-13, 11a-13a ... Uninterruptible power supply, 14, 18 ... 1 system bus-bar board, 15-17 ... Circuit breaker, 19 ... Relay circuit, 20 ... 2 system power system, 21- 23, 21a to 23a ... uninterruptible power supply, 24, 28 ... 2 system busbar board, 25-27 ... circuit breaker, 29 ... relay circuit, 31, 32 ... system control circuit, 40, 44 ... high speed switching board, 41, 42 ... Thyristor switch, 43 ... Switching command circuit, 45, 47 ... CT, 46, 48 ... Switching control circuit, 50, 54 ... High-speed switching panel, 51, 52 ... Thyristor switch, 53 ... Switching command circuit, 55, 57 ... CT, 56, 88 ... switching control circuit, 60, 64 ... high speed switching board, 61, 62 ... thyristor switch, 63 ... switching command circuit, 65, 67 ... CT, 66, 68 ... switching control circuit, 71, 78 ... auxiliary CT, 72 ~ 4, 83 ... switch, 75 ... diode circuit, 76, 77 ... shunt resistor, 79 ... resistor, 80 ... arithmetic element, 81 ... effective value arithmetic circuit, 82, 86 ... multiplication arithmetic unit 82, 83 ... addition arithmetic unit, 85 ... Setting device, 87... Comparison element, 90... High-speed switch drive circuit, 91... Signal output circuit, 93 and 93.

Claims (1)

Two sets of uninterruptible power supply systems consisting of multiple uninterruptible power supplies operating in parallel or single-unit uninterruptible power supplies, and switching to supply power to the corresponding load from either one of these two uninterruptible power supply systems In the uninterruptible power supply system comprising a plurality of panels, the output voltages of the uninterruptible power supply systems being phase-synchronized with each other,
Wherein the respective switching換盤, or when switching the power supply path from one of the uninterruptible power supply system to the other load corresponding to the uninterruptible power supply system, an uninterruptible power supply system of the other after the switching from falling into an overload state A switching determination means for determining whether or not in advance,
The switching determination means is
Estimated value calculation means for calculating the load current estimated value after switching based on the total value of the load current before switching in the uninterruptible power supply system at the switching destination and the corresponding load current value at the switching source;
The load current estimated value is formed from a comparison calculation means for performing a comparison calculation between the current rated output current value of the uninterruptible power supply system to be switched to,
An uninterruptible power supply system.

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