A power distribution transformer noise testing device and method

Abstract

The application provides a power distribution transformer noise testing device and method, comprising a first capacitor group, one end of which is connected with a voltage divider, and the other end of which is connected with a power supply; a second capacitor group, one end of which is connected with a first end of the power distribution transformer to be tested, and the other end of which is connected with a current transformer; the other end of the power supply is connected with the voltage divider, and the two ends of the voltage divider are respectively connected with a second end and a third end of the power distribution transformer to be tested; and the other end of the current transformer is connected with a fourth end of the power distribution transformer. The application adopts the capacitor group to compensate the inductance of the primary and secondary sides, improves the power factor of the experimental circuit, realizes the noise testing of the power distribution transformer under the rated working condition (voltage and current), and reduces the requirement of the experimental circuit on the power supply capacity.

Description

Technical Field

[0001] This invention relates to the field of power distribution transformer noise testing technology, and in particular to a power distribution transformer noise testing device and method. Background Technology

[0002] With the rapid pace of urbanization and the development of urban power infrastructure, a large number of power distribution rooms, substations, and other electrical equipment have been put into use in residential areas, resulting in a significant increase in electrical equipment and transformers being placed closer and closer to residential buildings. While this better meets residents' electricity needs, the noise generated by these transformers seriously affects their lives and work. Environmental noise from electrical equipment, particularly transformers, impacts the work and lives of nearby residents, leading to a year-on-year increase in noise complaints and disputes. Therefore, it is necessary to study the noise characteristics of transformers and conduct accurate noise testing on newly connected transformers.

[0003] In factories, due to power limitations that cannot meet measurement requirements, current methods cannot directly measure transformer noise under actual operating conditions. The sound levels of the core and windings are measured separately under rated voltage and no-load current, and under rated current and short-circuit voltage. These two sound levels are then added together to estimate the total sound level during actual operation. Measurements under rated voltage and no-load current primarily measure the transformer core noise, while measurements under rated current and short-circuit voltage primarily measure the winding noise. Simply adding these two sound levels, without considering the actual superposition effect of noise, introduces a certain error compared to the actual noise level. Furthermore, this measurement method cannot measure conditions such as transformer overload. On-site measurement of transformer noise is also limited by site constraints, such as noise reflection and background interference, making accurate noise measurement difficult. Summary of the Invention

[0004] The purpose of this invention is to provide a power distribution transformer noise testing device and method to solve the technical problems of existing transformer noise field measurement being limited by the site and having inaccurate test results.

[0005] On the one hand, a noise testing device for distribution transformers is provided, comprising:

[0006] The first capacitor bank has one end connected to a voltage divider and the other end connected to a power supply.

[0007] The second capacitor bank has one end connected to the first end of the distribution transformer under test, and the other end connected to the current transformer.

[0008] The other end of the power supply is connected to the voltage divider, and the two ends of the voltage divider are respectively connected to the second and third ends of the distribution transformer under test;

[0009] The other end of the current transformer is also connected to the fourth end of the distribution transformer.

[0010] Preferably, the operating voltage of the first capacitor is the same as that of the second capacitor.

[0011] Preferably, the operating current value of the first capacitor is the same as the operating current value of the second capacitor.

[0012] Preferably, the first capacitor contains a plurality of capacitors connected in series or in parallel.

[0013] Preferably, the second capacitor contains a plurality of capacitors connected in series or in parallel.

[0014] Preferably, the power supply can output multiple voltage values ​​corresponding to the received control commands.

[0015] On the other hand, a method for testing the noise of a distribution transformer is also provided, which is implemented by the aforementioned device, including:

[0016] The power supply can output various voltage values ​​corresponding to the received control commands;

[0017] The voltage and current values ​​of the distribution transformer under test are measured under the operating conditions using the voltage divider and the current transformer, respectively.

[0018] When the voltage and current values ​​of the distribution transformer under operating conditions do not meet the preset test conditions, the voltage value that the power supply needs to output is determined based on the voltage and current values ​​of the distribution transformer under operating conditions at this time.

[0019] The power supply is controlled to output the corresponding voltage according to the required output voltage value, and the noise of the distribution transformer under test is detected.

[0020] Preferably, the first capacitor is used to supplement the reactive power loss between the second and third terminals of the measured distribution transformer by the difference between the required output voltage value and the actual output voltage value when the power supply outputs voltage.

[0021] Preferably, the second capacitor is used to supplement the reactive power loss between the first and fourth terminals of the distribution transformer under test by the difference between the required output voltage value and the actual output voltage value when the power supply outputs voltage.

[0022] In summary, implementing the embodiments of the present invention has the following beneficial effects:

[0023] The noise testing device and method for distribution transformers provided by this invention use capacitor banks to compensate for the inductance of the primary and secondary sides, thereby improving the power factor of the experimental circuit; it enables noise testing of distribution transformers under rated operating conditions (voltage and current), and reduces the power supply capacity requirements of the test circuit. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of the present invention.

[0025] Figure 1 This is a schematic diagram of a power distribution transformer noise testing device according to an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the main flow of a power distribution transformer noise testing method in an embodiment of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0028] like Figure 1 The diagram shown is a schematic representation of an embodiment of a power distribution transformer noise testing device provided by the present invention. In this embodiment, the device includes:

[0029] The first capacitor bank has one end connected to a voltage divider and the other end connected to a power supply.

[0030] The second capacitor bank has one end connected to the first end of the distribution transformer under test, and the other end connected to the current transformer.

[0031] The other end of the power supply is connected to the voltage divider, and the two ends of the voltage divider are respectively connected to the second and third ends of the distribution transformer under test;

[0032] The other end of the current transformer is also connected to the fourth terminal of the distribution transformer. That is, the capacitor bank is used to compensate for reactive power on both the primary and secondary sides, the current transformer is used to measure the current value on the secondary side, and the voltage divider is used to measure the voltage value on the primary side. The capacitors are selected to match the inductance values ​​of the primary transformer (second capacitor bank) and the secondary transformer (second capacitor bank). The current transformer and voltage transformer monitor the voltage and current of the transformer to ensure it reaches its operating state. The voltage divider and current transformer are used to measure the voltage and current of the circuit to ensure the transformer can reach the required operating conditions.

[0033] In a specific embodiment, the operating voltage of the first capacitor is the same as that of the second capacitor. The operating current of the first capacitor is the same as that of the second capacitor. Multiple capacitors are connected in series or parallel within the first capacitor. Multiple capacitors are connected in series or parallel within the second capacitor. That is, the capacitor bank uses a series-parallel configuration, with the operating voltage of the secondary capacitor bank (second capacitor bank) equal to the secondary voltage of the transformer, and the operating current of the primary capacitor bank (first capacitor bank) equal to the primary current of the transformer. This effectively reduces the operating current and voltage of the selected capacitor bank. By using the capacitor bank to perform reactive power compensation on the transformer under test, noise testing of the transformer's actual operating conditions can be achieved under conditions of a relatively small power supply.

[0034] In this embodiment, the power supply can output various voltage values ​​corresponding to the received control commands. The power supply is adjustable to regulate the output voltage. Devices such as column-type voltage regulators can be used to adjust the power supply voltage to achieve the rated operating conditions of the transformer under test. Since the power factor of the test circuit is high, the capacity requirement of the adjustable power supply can be reduced.

[0035] like Figure 2 As shown, an embodiment of the present invention also provides a method for testing the noise of a distribution transformer, which is implemented using the device for testing the noise of the distribution transformer, including:

[0036] The power supply can output various voltage values ​​corresponding to the received control commands;

[0037] The voltage and current values ​​of the distribution transformer under test are measured under the operating conditions using the voltage divider and the current transformer, respectively.

[0038] When the voltage and current values ​​of the distribution transformer under operating conditions do not meet the preset test conditions, the voltage value that the power supply needs to output is determined based on the voltage and current values ​​of the distribution transformer under operating conditions at this time.

[0039] The power supply is controlled to output the corresponding voltage according to the required output voltage value, and the noise of the distribution transformer under test is detected.

[0040] In this embodiment, the first capacitor is used to supplement the reactive power loss between the second and third terminals of the distribution transformer under test by using the difference between the required output voltage value and the actual output voltage value when the power supply outputs voltage. The second capacitor is used to supplement the reactive power loss between the first and fourth terminals of the distribution transformer under test by using the difference between the required output voltage value and the actual output voltage value when the power supply outputs voltage.

[0041] It should be noted that the methods described in the above embodiments correspond to the devices described in the above embodiments. Therefore, the parts of the methods described in the above embodiments that are not described in detail can be obtained by referring to the contents of the devices described in the above embodiments, and will not be repeated here.

[0042] In summary, implementing the embodiments of the present invention has the following beneficial effects:

[0043] The noise testing device and method for distribution transformers provided by this invention use capacitor banks to compensate for the inductance of the primary and secondary sides, thereby improving the power factor of the experimental circuit; it enables noise testing of distribution transformers under rated operating conditions (voltage and current), and reduces the power supply capacity requirements of the test circuit.

[0044] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for testing the noise of a distribution transformer, implemented using a distribution transformer noise testing device, the device comprising: The first capacitor bank has one end connected to a voltage divider and the other end connected to a power supply. The second capacitor bank has one end connected to the first terminal of the distribution transformer under test, and the other end connected to a current transformer; the other end of the power supply is connected to the voltage divider, and the two ends of the voltage divider are also connected to the second and third terminals of the distribution transformer under test, respectively; the other end of the current transformer is also connected to the fourth terminal of the distribution transformer; the operating voltage value of the first capacitor is the same as the operating voltage value of the second capacitor, and the operating current value of the first capacitor is the same as the operating current value of the second capacitor; The method is characterized by comprising: The power supply can output various voltage values ​​corresponding to the received control commands; The voltage and current values ​​of the distribution transformer under test are measured under the operating conditions using the voltage divider and the current transformer, respectively. When the voltage and current values ​​of the distribution transformer under operating conditions do not meet the preset test conditions, the voltage value that the power supply needs to output is determined based on the voltage and current values ​​of the distribution transformer under operating conditions at this time. The power supply is controlled to output the corresponding voltage according to the required output voltage value, and the noise of the distribution transformer under test is detected. The first capacitor is used to supplement the reactive power loss between the second and third terminals of the measured distribution transformer by the difference between the required output voltage value and the actual output voltage value when the power supply outputs voltage. The second capacitor is used to supplement the reactive power loss between the first and fourth terminals of the distribution transformer under test by using the difference between the required output voltage value and the actual output voltage value when the power supply outputs voltage.

2. The method as described in claim 1, characterized in that, The first capacitor contains multiple capacitors connected in series or in parallel.

3. The method as described in claim 2, characterized in that, The second capacitor contains multiple capacitors connected in series or in parallel.

4. The method as described in claim 1, characterized in that, The power supply can output various voltage values ​​corresponding to the received control commands.

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