Frequency regulation method and apparatus
A frequency regulation method and apparatus is applied to an insulation impedance detection apparatus in a direct current power system, and relates to the field of security monitoring technologies of a direct current electrical system. The method includes: collecting sampling voltages at a sampling point for at least three time points; determining a voltage frequency regulation manner based on the sampling voltages, obtained through sampling, at the at least three time points; and then regulating a voltage frequency of a power supply according to the determined voltage frequency regulation manner. The voltage frequency of the power supply can be regulated based on the at least three sampling voltages obtained through sampling. Therefore, the insulation impedance detection apparatus reduces insulation impedance detection duration while ensuring accuracy of measured insulation impedance.
1. A frequency regulation method, applied to an insulation impedance detection apparatus in a direct current power system, comprising:
collecting sampling voltages at a sampling point for at least three time points;
determining a voltage frequency regulation manner based on the at least three sampling voltages; and
dynamically regulating a voltage frequency of a power supply in the insulation impedance detection apparatus according to the voltage frequency regulation manner to obtain a voltage cycle of the power supply equal to an insulation time constant of the insulation impedance detection apparatus.
2. The frequency regulation method of claim 1 , wherein determining the voltage frequency regulation manner based on the at least three sampling voltages comprises:
determining that the voltage frequency regulation manner is maintaining the voltage frequency unchanged when the at least three sampling voltages meet a first function relationship;
determining that the voltage frequency regulation manner is increasing the voltage frequency by a first step when the at least three sampling voltages do not meet the first function relationship but meet a second function relationship; or
determining that the voltage frequency regulation manner is reducing the voltage frequency by a second step when the at least three sampling voltages do not meet the first function relationship but meet a third function relationship.
3. The frequency regulation method according to of claim 2 , wherein the voltage cycle of the power supply in the insulation impedance detection apparatus is T, and wherein collecting sampling voltages at the sampling point for the at least three time points comprises:
collecting a first sampling voltage at a first sampling point at a time point zero of the voltage cycle, collecting a second sampling voltage at a second sampling point at a time point T/4 of the voltage cycle, and collecting a third sampling voltage at a third sampling point at a time point T/2 of the voltage cycle, or
collecting a first sampling voltage at a first sampling point at a time point T/2 of the voltage cycle, collecting a second sampling voltage at a second sampling point at a time point 3T/4 of the voltage cycle, and collecting a third sampling voltage at a third sampling point at a time point T of the voltage cycle.
4. The frequency regulation method of claim 3 , wherein the first function relationship is
1
2
(
V
3
+
V
1
)
+
k
2
2
V
3
-
V
1
<
V
2
<
1
2
(
V
3
+
V
1
)
+
k
1
2
V
3
-
V
1
,
wherein the second function relationship is
V
2
>
1
2
(
V
3
+
V
1
)
+
k
1
2
V
3
-
V
1
,
wherein the third function relationship is
V
2
<
1
2
(
V
3
+
V
1
)
+
k
2
2
V
3
-
V
1
,
wherein V 1 is the first sampling voltage, wherein V 2 is the second sampling voltage, wherein V 3 is the third sampling voltage, wherein k 1 ∈(0,1), wherein k 2 ∈(0,1), and wherein k 2 <k 1 .
5. The frequency regulation method of claim 3 , wherein the first function relationship is |V 3 |−|V 2 |>ΔV a and |V 2 |−|V 1 |>ΔV b , wherein the second function relationship is |V 3 |−|V 2 |<ΔV a , wherein the third function relationship is |V 2 |−|V 1 |<ΔV b , wherein V 1 is the first sampling voltage, wherein V 2 is the second sampling voltage, wherein V 3 is the third sampling voltage, and wherein ΔV a and ΔV b are constants.
6. A frequency regulation apparatus, applied to an insulation impedance detection apparatus in a direct current power system, comprising:
a sampling unit configured to collect sampling voltages at a sampling point for at least three time points;
a processing unit configured to determine a voltage frequency regulation manner based on the at least three sampling voltages; and
a regulation unit configured to dynamically regulate a voltage frequency of a power supply in the insulation impedance detection apparatus according to the voltage frequency regulation manner to obtain a voltage cycle of the power supply equal to an insulation time constant of the insulation impedance detection apparatus.
7. The frequency regulation apparatus of claim 6 , wherein the processing unit is further configured to:
determine that the voltage frequency regulation manner is to maintain the voltage frequency unchanged when the at least three sampling voltages meet a first function relationship;
determine that the voltage frequency regulation manner is to increase the voltage frequency by a first step when the at least three sampling voltages do not meet the first function relationship but meet a second function relationship; or
determine that the voltage frequency regulation manner is to reduce the voltage frequency by a second step when the at least three sampling voltages do not meet the first function relationship but meet a third function relationship.
8. The frequency regulation apparatus of claim 7 , wherein the voltage cycle of the power supply in the insulation impedance detection apparatus is T, and wherein the sampling unit is further configured to:
collect a first sampling voltage at a first sampling point at a time point zero of the voltage cycle, collect a second sampling voltage at a second sampling point at a time point T/4 of the voltage cycle, and collect a third sampling voltage at a third sampling point at a time point T/2 of the voltage cycle, or
collect a first sampling voltage at a first sampling point at a time point T/2 of the voltage cycle, a second sampling voltage at a second sampling point at a time point 3T/4 of the voltage cycle, and a third sampling voltage at a third sampling point at a time point T of the voltage cycle.
9. The frequency regulation apparatus of claim 8 , wherein the first function relationship is
1
2
(
V
3
+
V
1
)
+
k
2
2
V
3
-
V
1
<
V
2
<
1
2
(
V
3
+
V
1
)
+
k
1
2
V
3
-
V
1
wherein the second function relationship is
V
2
>
1
2
(
V
3
+
V
1
)
+
k
1
2
V
3
-
V
1
,
wherein the third function relationship is
V
2
<
1
2
(
V
3
+
V
1
)
+
k
2
2
V
3
-
V
1
,
wherein V 1 is the first sampling voltage, wherein V 2 is the second sampling voltage, wherein V 3 is the third sampling voltage, wherein k 1 ∈(0,1), wherein k 2 ∈(0,1), and wherein k 2 <k 1 .
10. The frequency regulation apparatus of claim 8 , wherein the first function relationship is |V 3 |−|V 2 |>ΔV a and |V 2 |−|V 1 |>ΔV b , wherein the second function relationship is |V 3 |−|V 2 |>ΔV a , wherein the third function relationship is |V 2 |−|V 1 |<ΔV b , wherein V 1 is the first sampling voltage, wherein V 2 is the second sampling voltage, wherein V 3 is the third sampling voltage, and wherein ΔV a and ΔV b are constants.
11. A frequency regulation apparatus, applied to an insulation impedance detection apparatus in a direct current power system, comprising:
a memory comprising instructions; and
a processor coupled to the memory and configured to execute the instructions, which cause the processor to be configured to:
collect sampling voltages at a sampling point for at least three time points;
determine a voltage frequency regulation manner based on the at least three sampling voltages; and
dynamically regulate a voltage frequency of a power supply in the insulation impedance detection apparatus according to the voltage frequency regulation manner to obtain a voltage cycle of the power supply equal to an insulation time constant of the insulation impedance detection apparatus.
12. The frequency regulation apparatus of claim 11 , wherein the processor is further configured to:
determine that the voltage frequency regulation manner is maintaining the voltage frequency unchanged when the at least three sampling voltages meet a first function relationship.
13. The frequency regulation apparatus of claim 12 , wherein the processor is further configured to:
determine that the voltage frequency regulation manner is increasing the voltage frequency by a first step when the at least three sampling voltages do not meet the first function relationship but meet a second function relationship.
14. The frequency regulation apparatus of claim 12 , wherein the processor is further configured to:
determine that the voltage frequency regulation manner is reducing the voltage frequency by a second step when the at least three sampling voltages do not meet the first function relationship but meet a third function relationship.
15. The frequency regulation apparatus of claim 11 , wherein the voltage cycle of the power supply in the insulation impedance detection apparatus is T.
16. The frequency regulation apparatus of claim 15 , wherein the processor is further configured to collect a first sampling voltage at a first sampling point at a time point zero of the voltage cycle, collect a second sampling voltage at a second sampling point at a time point T/4 of the voltage cycle, and collect a third sampling voltage at a third sampling point at a time point T/2 of the voltage cycle.
17. The frequency regulation apparatus of claim 15 , wherein the processor is further configured to collect a first sampling voltage at a first sampling point at a time point T/2 of the voltage cycle, collect a second sampling voltage at a second sampling point at a time point 3T/4 of the voltage cycle, and collect a third sampling voltage at a third sampling point at a time point T of the voltage cycle.
18. The frequency regulation apparatus of claim 11 , wherein the processor is further configured to regulate the voltage frequency of the power supply in the insulation impedance detection apparatus further according to detection precision requirements.
19. The frequency regulation apparatus of claim 11 , wherein the processor is further configured to regulate the voltage frequency of the power supply in the insulation impedance detection apparatus further according to detection duration requirements.
20. The frequency regulation apparatus of claim 11 , wherein the at least three time points of the sampling point are set depending on a requirement.