Three-phase AC voltage step simulation test device and method

Abstract

The invention particularly relates to a three-phase alternating-current voltage step simulation test device, which comprises a mains supply (1), a three-phase voltage regulating transformer (13), a UPS (Uninterrupted Power Supply) (4) and a load (5) which are sequentially connected in series, on a circuit in which the three-phase voltage regulating transformer (13) is connected with the UPS (4) in series, each phase is connected with a slide rheostat (2) in series; and a three-phase air switch (3) is connected in parallel between two ends of each slide rheostat (2). The invention also relates to a three-phase AC voltage step simulation test method. According to the invention, an upstream three-phase AC voltage step simulation test of the UPS is realized.

Description

Technical Field

[0001] The present invention relates to the field of electrical technology, and in particular to a three-phase AC voltage step simulation test device and method. Background Art

[0002] Considering the safe and stable operation of nuclear power plants, important instruments, cabinets and control loads related to the grid and reactor protection and monitoring are all powered by UPS uninterruptible power supply. Therefore, UPS uninterruptible power supply needs to ensure that it can continuously and stably transmit electric energy to the downstream. When large motor equipment such as the main pump motor is started or stopped, it will cause large instantaneous step fluctuations in the plant voltage. In order to ensure that the UPS uninterruptible power supply can still continuously and stably transmit electric energy to the downstream under the condition of instantaneous step fluctuations in voltage, it is necessary to conduct AC voltage step simulation test on the upstream of the UPS uninterruptible power supply.

[0003] However, existing voltage regulating devices all have a manual voltage regulation process and cannot simulate the instantaneous step voltage fluctuation caused by large motor equipment, and cannot ensure the power supply of the UPS uninterruptible power supply under such working conditions, posing a safety hazard. Summary of the invention

[0004] The purpose of the present invention is to provide a three-phase AC voltage step simulation test device and method to solve the problem that the existing voltage regulating equipment cannot simulate the upstream three-phase AC voltage step test of the UPS uninterruptible power supply, and to realize the upstream three-phase AC voltage step simulation test of the UPS uninterruptible power supply.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A three-phase AC voltage step simulation test device comprises a mains power supply, a three-phase voltage regulating transformer, a UPS uninterruptible power supply and a load which are connected in series in sequence; in a circuit in which the three-phase voltage regulating transformer and the UPS uninterruptible power supply are connected in series, each phase is connected in series with a sliding rheostat; and a three-phase circuit breaker is connected in parallel between the two ends of each sliding rheostat.

[0007] As one possible implementation, a UPS uninterruptible power supply includes an AC input terminal A, a rectifier A, an inverter A and an AC output terminal A which are connected in sequence.

[0008] As another achievable method, a UPS uninterruptible power supply includes an AC input terminal B, a rectifier B, a rectifier C, a diode, an inverter B, an AC input terminal C, an AC output terminal B and a battery; the AC input terminal B is connected in series with the input terminal of the rectifier B; the output terminal of the rectifier B is connected in series with the input terminal of the inverter B, and the output terminal of the rectifier B is connected in parallel with the rectifier C and the output terminal of the battery through a diode; the output terminal of the inverter B is connected in series with the AC output terminal B, and the output terminal of the rectifier C is connected in parallel with the output terminal of the battery.

[0009] The present invention also provides a three-phase AC voltage step simulation test method, using the above three-phase AC voltage step simulation test device, comprising the following steps:

[0010] By adjusting the output voltage of the three-phase voltage regulating transformer to +10% of the rated input voltage of the UPS, the upper limit voltage of the UPS AC input voltage can be confirmed;

[0011] Disconnect the three-phase circuit breaker, and adjust the output voltage of the sliding rheostat to -15% of the rated input voltage of the UPS uninterruptible power supply by using the resistance voltage division principle, so as to determine the lower limit voltage of the UPS uninterruptible power supply AC input voltage;

[0012] Close the three-phase circuit breaker, short-circuit the sliding rheostat to bypass, and the UPS uninterruptible power supply AC input voltage steps to the upper limit voltage to achieve the UPS uninterruptible power supply AC input voltage positive step, and observe the operating status of the UPS uninterruptible power supply at this time;

[0013] Disconnect the three-phase circuit breaker, put the sliding rheostat into operation, and the UPS uninterruptible power supply AC input voltage steps to the lower limit voltage, realizing a negative step of the UPS uninterruptible power supply AC input voltage, and observe the operating status of the UPS uninterruptible power supply at this time.

[0014] Beneficial technical effects of the present invention:

[0015] The three-phase AC voltage step simulation test device and method of the present invention realize the three-phase AC voltage step simulation test upstream of the UPS uninterruptible power supply, and can detect whether the UPS uninterruptible power supply can stabilize the DC voltage, thereby preventing the UPS uninterruptible power supply from being unable to stabilize the DC voltage and causing the inverter to shut down due to high DC input voltage, resulting in power failure of the inverter downstream load, thereby ensuring the safe and reliable operation of network-related equipment during unit operation; the three-phase AC voltage is provided by the mains, the three-phase AC voltage is adjusted by a sliding rheostat, and the three-phase AC voltage positive step or negative step is performed by a three-phase circuit breaker connected in parallel at both ends of the sliding rheostat. The equipment occupies a small working space and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of a three-phase AC voltage step simulation test device;

[0017] Figure 2 It is a structural schematic diagram of an embodiment of a UPS uninterruptible power supply;

[0018] Figure 3 It is a structural schematic diagram of another embodiment of a UPS uninterruptible power supply.

[0019] In the figure, 1. AC power; 2. sliding rheostat; 3. three-phase circuit breaker; 4. UPS uninterruptible power supply; 5. load; 13. three-phase voltage regulating transformer; 6. AC input terminal A; 8. rectifier A; 11. inverter A; 12. AC output terminal A; 7. AC input terminal B; 9. rectifier B; 10. rectifier C; 14. AC input terminal C; 15. diode; 16. inverter B; 17. AC output terminal B; 18. battery. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is described clearly and completely below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] See also Figure 1 The present embodiment provides a three-phase AC voltage step simulation test device, comprising a mains 1, a three-phase voltage regulating transformer 13, a UPS uninterruptible power supply 4 and a load 5 connected in series in sequence; in the circuit in which the three-phase voltage regulating transformer 13 and the UPS uninterruptible power supply 4 are connected in series, a sliding rheostat 2 is connected in series in each phase; a three-phase circuit breaker 3 is connected in parallel between the two ends of each sliding rheostat 2.

[0023] The city power 1 flows into the UPS uninterruptible power supply 4 through the three-phase voltage regulating transformer 13, and after being rectified and inverted by the UPS uninterruptible power supply 4, supplies power to the load 5.

[0024] In order to simulate the three-phase AC voltage jump of the UPS uninterruptible power supply 4 that may be caused by the startup and mediation of large motor equipment, the upper limit of the three-phase AC voltage input to the UPS uninterruptible power supply 4 is adjusted by connecting a three-phase voltage regulating transformer 13 in series between the mains 1 and the UPS uninterruptible power supply 4; by utilizing the principle of resistance voltage division, a sliding rheostat 2 is connected in series between the three-phase voltage regulating transformer 13 and the UPS uninterruptible power supply 4, and the lower limit of the three-phase AC voltage input to the UPS uninterruptible power supply 4 is adjusted by adjusting the resistance value of the sliding rheostat 2; a three-phase circuit breaker 3 is connected in parallel between the two ends of the sliding rheostat 2, and the direction of the positive or negative step change of the three-phase AC voltage input to the UPS uninterruptible power supply 4 is controlled by the opening and closing of the three-phase circuit breaker 3.

[0025] refer to Figure 2 In this embodiment, as one of the feasible ways, the UPS uninterruptible power supply 4 includes an AC input terminal A6, a rectifier A8, an inverter A11 and an AC output terminal A12 which are connected in sequence.

[0026] The three-phase AC voltage input from the AC input terminal A6 is rectified into a DC voltage by the rectifier A8 and then transmitted to the inverter A11. The inverter A11 inverts the three-phase AC voltage into the required voltage and then flows to the output terminal A12.

[0027] When the three-phase circuit breaker 3 is opened and closed to control the sliding rheostat 2 to make the voltage at the AC input terminal A6 step, it can be observed whether the rectifier A8 has the voltage stabilization function. If the DC voltage cannot be stabilized, the DC voltage flowing into the inverter A11 will be too high, causing high voltage shutdown, resulting in no voltage at the output terminal A12, which will cause the load to be at risk of power failure.

[0028] refer to Figure 3 In this embodiment, as another achievable method, the UPS uninterruptible power supply 4 includes an AC input terminal B7, a rectifier B9, a rectifier C10, a diode 15, an inverter B16, an AC input terminal C14, an AC output terminal B17 and a battery 18; the AC input terminal B7 is connected in series with the input terminal of the rectifier B9; the output terminal of the rectifier B9 is connected in series with the input terminal of the inverter B16, and the output terminal of the rectifier B9 is connected in parallel with the output terminal of the rectifier C10 and the output terminal of the battery 18 through the diode 15; the output terminal of the inverter B16 is connected in series with the AC output terminal B17, and the output terminal of the rectifier C10 is connected in parallel with the output terminal of the battery 18.

[0029] The three-phase AC voltage step fluctuation at the AC input terminal B7 is simulated by the three-phase voltage regulating transformer 13, the sliding rheostat 2 and the three-phase circuit breaker 3, and it is found that the AC output terminal B17 downstream is de-energized.

[0030] The three-phase AC voltage input from the AC input terminal B7 is rectified into a DC voltage by the rectifier B9, and provides a DC voltage for the inverter B16. When the rectifier B9 loses power, the rectifier C10 and the battery 18 provide a DC voltage for the inverter B16; however, a diode 15 is provided between the rectifier B9 and the battery 18, which causes a step voltage at the upstream voltage of the rectifier B9, and the output voltage of the rectifier B9 also increases accordingly. Due to the blocking of the diode 15, the battery 18 cannot stabilize the DC input voltage on the inverter B16 side, causing the inverter B16 to shut down due to high DC input voltage, causing the downstream load to lose power.

[0031] The present invention also provides a three-phase AC voltage step simulation test method, using the above three-phase AC voltage simulation test device, comprising the following steps:

[0032] By adjusting the output voltage of the three-phase voltage regulating transformer 13 to +10% of the rated input voltage of the UPS uninterruptible power supply 4, the upper limit voltage of the AC input voltage of the UPS uninterruptible power supply 4 is confirmed;

[0033] Disconnect the three-phase circuit breaker 3, and adjust the output voltage of the sliding rheostat 2 to -15% of the rated input voltage of the UPS uninterruptible power supply 4 by adjusting the sliding rheostat 2 using the resistance voltage division principle, so as to determine the lower limit voltage of the AC input voltage of the UPS uninterruptible power supply 4;

[0034] Close the three-phase circuit breaker 3, short-circuit the sliding rheostat 2 to bypass, and the AC input voltage of the UPS uninterruptible power supply 4 steps to the upper limit voltage, realizing the positive step of the AC input voltage of the UPS uninterruptible power supply 4, and observe the operating status of the UPS uninterruptible power supply 4 at this time;

[0035] Disconnect the three-phase circuit breaker 3, put the sliding rheostat 2 into operation, and the AC input voltage of the UPS uninterruptible power supply 4 steps to the lower limit voltage, realizing a negative step of the AC input voltage of the UPS uninterruptible power supply, and observe the operating status of the UPS uninterruptible power supply 4 at this time.

[0036] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A three-phase AC voltage step simulation test device, characterized in that: The invention comprises a city power supply (1), a three-phase voltage regulating transformer (13), a UPS uninterruptible power supply (4) and a load (5) which are connected in series in sequence; in a circuit in which the three-phase voltage regulating transformer (13) and the UPS uninterruptible power supply (4) are connected in series, a sliding rheostat (2) is connected in series on each phase; and a three-phase circuit breaker (3) is connected in parallel between the two ends of each sliding rheostat (2).

2. The three-phase AC voltage step simulation test device according to claim 1, characterized in that: The UPS uninterruptible power supply (4) comprises an AC input terminal A (6), a rectifier A (8), an inverter A (11) and an AC output terminal A (12) which are connected in sequence.

3. The three-phase AC voltage step simulation test device according to claim 1, characterized in that: The UPS uninterruptible power supply (4) comprises an AC input terminal B (7), a rectifier B (9), a rectifier C (10), a diode (15), an inverter B (16), an AC input terminal C (14), an AC output terminal B (17) and a storage battery (18); the AC input terminal B (7) is connected in series with the input terminal of the rectifier B (9); the output terminal of the rectifier B (9) is connected in series with the input terminal of the inverter B (16); the output terminal of the rectifier B (9) is connected in parallel with the output terminal of the rectifier C (10) and the output terminal of the storage battery (18) through the diode (15); the output terminal of the inverter B (16) is connected in series with the AC output terminal B (17), and the output terminal of the rectifier C (10) is connected in parallel with the output terminal of the storage battery (18).

4. A three-phase AC voltage step simulation test method, characterized in that: The three-phase AC voltage step simulation test device according to any one of claims 1 to 3 comprises the following steps: By adjusting the output voltage of the three-phase voltage regulating transformer (13) to +10% of the rated input voltage of the UPS uninterruptible power supply (4), the upper limit voltage of the AC input voltage of the UPS uninterruptible power supply (4) is confirmed; Disconnect the three-phase circuit breaker (3), and adjust the output voltage of the sliding rheostat (2) to -15% of the rated input voltage of the UPS uninterruptible power supply (4) by adjusting the sliding rheostat (2) using the resistance voltage division principle, so as to determine the lower limit voltage of the AC input voltage of the UPS uninterruptible power supply (4); The three-phase circuit breaker (3) is closed, the sliding rheostat (2) is short-circuited and bypassed, and the AC input voltage of the UPS uninterruptible power supply (4) steps to the upper limit voltage, realizing a positive step of the AC input voltage of the UPS uninterruptible power supply (4), and the operating state of the UPS uninterruptible power supply (4) is observed at this time; The three-phase circuit breaker (3) is disconnected, the sliding rheostat (2) is put into operation, and the AC input voltage of the UPS uninterruptible power supply (4) steps to the lower limit voltage, realizing a negative step of the AC input voltage of the UPS uninterruptible power supply. The operating status of the UPS uninterruptible power supply (4) is observed at this time.

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