CN108646180A - Hydroelectric units primary frequency modulation dynamic realtime performance tests system and its test method - Google Patents
Hydroelectric units primary frequency modulation dynamic realtime performance tests system and its test method Download PDFInfo
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- CN108646180A CN108646180A CN201810866670.XA CN201810866670A CN108646180A CN 108646180 A CN108646180 A CN 108646180A CN 201810866670 A CN201810866670 A CN 201810866670A CN 108646180 A CN108646180 A CN 108646180A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/34—Testing dynamo-electric machines
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Abstract
The present invention discloses hydroelectric units primary frequency modulation dynamic realtime performance test system and its test method,Test system includes data collecting card,The AI0 analog inputs port of the data collecting card,AI1 analog inputs port and AI2 analog inputs port are connect with the port of each sensor of water turbine set respectively,The A/D conversion modules of the data collecting card are connect with dynamic realtime computing module pci bus,The dynamic realtime computing module is connect with frequency generator pci bus,The ports Ctr0 of the frequency generator and the governor frequency collection port of water turbine set connect,The frequency pulse signal of grid simulation can be accurately exported in real time,Ensure the Phase Continuation of frequency pulse signal,The real-time transform of accurate simulating grid frequency,It is easy to implement and completes the performance test of hydroelectric units primary frequency modulation in dynamic process.
Description
Technical field
The present invention relates to hydroelectric units primary frequency modulation testing field more particularly to hydroelectric units primary frequency modulation dynamic real-times
System and its test method can be tested.
Background technology
As ratio of the large sized unit in power grid is continuously increased, load peak-valley difference caused by the variation of power grid power structure
It gradually increases, the problem of mains frequency stability is increasingly taken seriously, and the primary frequency modulation performance of Hydropower Unit is largely
On affect the stabilization of mains frequency.It is cumbersome and time consuming by artificial external device hair frequency when carrying out primary frequency modulation experiment,
It cannot be satisfied equipment synchronization again, unit can not be reacted completely under the practical fluctuation of mains frequency, unit moves primary frequency modulation
State responds effect, it is therefore desirable to the automatic computer sim- ulation mains frequency dynamic fluctuation process of equipment, then exported and led to by device frequency
Road output frequency is necessary to carry out the dynamic primary frequency modulation test of unit.
And requirements of the national standard Large Speed Governor frequency measurement dead zone is within 0.02% simultaneously and frequency resolution will reach
Within 0.01Hz, and usually generally to reach 10 times of measurand precision or more to the measurement accuracy of test device, thus require
The frequency resolution of the frequency of signal generator of general measure device should be not more than 0.001Hz, i.e., its basic crystal oscillator frequency is minimum
It is required that being 2.5MHz.The hair frequency method of the general primary frequency modulation test equipment of existing market is substantially matches total number by crystal oscillator
Device carries out, although the crystal oscillator frequency of many equipment in market alreadys exceed the frequency of 2.5MHz, it sends out frequency principle in the company of transmission
When the frequency pulse signal of continuous variation, it may appear that the phase of frequency pulse signal is discontinuous, thus appears in a frequency
When signal period does not complete, counter variation numerical value causes terminal to calculate, and ultimately forms discontinuous frequency pulse signal.If
A consecutive variations frequency pulse signal is generated, this phenomenon is particularly evident.
Therefore it is dynamic to mains frequency to realize how to design and develop a set of frequency pulse signal that can send continuous variable
The emulation of state, while it is this patent that the precision of its frequency pulse signal sent, which is far longer than the frequency dead band of national Specification,
It solves the problems, such as.
Invention content
The technical problem to be solved by the present invention is to：The present invention is tested by hydroelectric units primary frequency modulation dynamic realtime performance
System and its test method, it is cumbersome and time consuming by artificial external device hair frequency when solving to carry out primary frequency modulation experiment, and nothing
Method meets equipment synchronization, can not react the unit dynamic response of unit to primary frequency modulation under the practical fluctuation of mains frequency completely
The frequency resolution that the frequency of signal generator of the problem of effect and general measure device meets actual needs is can not the company of being formed
The problem of continuous frequency pulse signal.
The technical scheme is that：Hydroelectric units primary frequency modulation dynamic realtime performance tests system, including data acquisition
Card, AI0 analog inputs port, AI1 analog inputs port and the AI2 analog inputs port difference of the data collecting card
It is connect with the port of each sensor of water turbine set, A/D conversion modules and the dynamic realtime computing module of the data collecting card
Pci bus connects, and the dynamic realtime computing module is connect with frequency generator pci bus, the Ctr0 of the frequency generator
Port and the governor frequency collection port of water turbine set connect.
The frequency generator includes high-speed phase accumulator, SIN function register, digital-to-analogue conversion and low-pass filter,
Wherein high-speed phase accumulator, SIN function register, digital-to-analogue conversion and low-pass filter all connecing by serial input mode
Mouth connection.
Hydroelectric units primary frequency modulation dynamic realtime performance tests the test method of system, includes the following steps：
Step 1：It is tired to be sent to phase by the frequency control word K that phase accumulator is calculated by dynamic realtime computing module
Phase value is sent in SIN function register after adding device, phase accumulator tired, corresponding signal value is calculated, is passing through modulus
Conversion and low-pass filtering module are exported, and amplify to obtain corresponding required frequency signal by amplifying circuit come simulated grid frequency
The fluctuation of rate；
Step 2：Frequency generator realizes water power according to the governor of the undulated control water turbine set of simulated grid frequency
The dynamic primary frequency modulation performance testing experiment of unit；
Step 3：Data collecting card is defeated by AI0 analog inputs port, AI1 analog inputs port and AI2 analog quantitys
Inbound port acquires the guide vane opening signal, active power signal and spiral case hydraulic signal of water turbine set respectively；
Step 4：Guide vane opening signal, active power signal and spiral case hydraulic signal in step 3 is adopted by data
A/D conversion modules inside truck are handled, and are converted to digital signal and are inputed to dynamic realtime computing module；
Step 5：Dynamic realtime computing module calculates the active regulating time of water turbine set, the active amplitude of accommodation, active stabilization
Time and the actual integration electricity in primary frequency modulation adjustment process.
Actual integration electricity process of the dynamic realtime computing module calculating in primary frequency modulation adjustment process is in step 5：
It is calculated by the following formula the rotating speed and mains frequency relationship of water turbine set first：
In formula, n is Hydropower Unit rotating speed, and unit is to turn/min, and f is mains frequency, and unit Hz, p are generator magnetic pole
Logarithm；
Then, the theoretical device electricity of primary frequency modulation is calculated according to following formula：
In formula, QtDevice electricity, unit kWh are acted for theory；PrFor unit rated power, unit kW；t0It is one
Secondary frequency modulation starts actuation time, unit s；Δ t primary frequency modulation process durations, unit s；Δ f is the frequency actually measured
Rate deviation, unit Hz；
Finally, the actual integration electricity of primary frequency modulation is calculated according to following formula：
In formula, QrFor actual act device electricity, unit kWh；PtFor unit actual test active power, unit is
kW；P0The practical measurement active power of unit, unit kW before being acted for primary frequency modulation.
Dynamic realtime computing module calculates whether the water turbine set active governing response time is less than 3s, active tune in step 5
Whether section amplitude can reach rated load 10%, whether active adjusting stabilization time is less than 60s, device electricity actual act load
Whether the 50% of theoretical capacity is reached.
The frequency control word K for calculating phase accumulator in step 5 by dynamic realtime computing module, is sent to phase
Phase value is sent in SIN function register after phase accumulator is tired, calculates corresponding signal value, passing through mould by accumulator
Number conversion and low-pass filtering module are exported, then amplify to obtain corresponding required frequency signal to emulate electricity by amplifying circuit
The fluctuation of net frequency.
In frequency generator module, including clock, phase accumulator, SIN function register, A-D converter, low pass
Filter and signal amplification circuit.Increment control algorithm K is calculated by computing module, accumulator is by initial phase and controls data K phases
Add, the result of addition is sent to the output end of phase accumulator, while phase accumulator is by the cenotype of the calculating of upper a cycle
Position data feed back to input terminal, under next clock, continue data K and are added, the phase value of output end is transported to sine
In function register, the output of binary waveform data is gone out by phase address lookup, then be input to analog-to-digital conversion module progress
Analog quantity is converted, and so that it is transformed to smooth waveform by low-pass filtering, is finally being amplified driving by signal amplification
Hydrogovernor.
The beneficial effects of the invention are as follows：The present invention can accurately export the frequency pulse signal of grid simulation in real time, protect
The Phase Continuation of frequency pulse signal is demonstrate,proved, the real-time transform of accurate simulating grid frequency is easy to implement and completes dynamic process
The performance test of middle hydroelectric units primary frequency modulation.
Description of the drawings
Fig. 1 is the structural schematic diagram of apparatus of the present invention；
Fig. 2 is the structural schematic diagram of apparatus of the present invention frequency generator.
Specific implementation mode
Below in conjunction with the accompanying drawings and invention is described further in specific embodiment：
Hydroelectric units primary frequency modulation dynamic realtime performance tests system, including data collecting card, the data collecting card
AI0 analog inputs port, AI1 analog inputs port and AI2 analog inputs port respectively with each sensing of water turbine set
The port of device connects, and the A/D conversion modules of the data collecting card are connect with dynamic realtime computing module pci bus, described dynamic
The real-time computing module of state is connect with frequency generator pci bus, the ports Ctr0 of the frequency generator and the tune of water turbine set
Fast device frequency collection port connects.
The frequency generator includes high-speed phase accumulator, SIN function register, digital-to-analogue conversion and low-pass filter,
Wherein high-speed phase accumulator, SIN function register, digital-to-analogue conversion and low-pass filter all connecing by serial input mode
Mouth connection.
Hydroelectric units primary frequency modulation dynamic realtime performance tests the test method of system, includes the following steps：
Step 1：It is tired to be sent to phase by the frequency control word K that phase accumulator is calculated by dynamic realtime computing module
Phase value is sent in SIN function register after adding device, phase accumulator tired, corresponding signal value is calculated, is passing through modulus
Conversion and low-pass filtering module are exported, and amplify to obtain corresponding required frequency signal by amplifying circuit come simulated grid frequency
The fluctuation of rate；
Step 2：Frequency generator realizes water power according to the governor of the undulated control water turbine set of simulated grid frequency
The dynamic primary frequency modulation performance testing experiment of unit；
Step 3：Data collecting card is defeated by AI0 analog inputs port, AI1 analog inputs port and AI2 analog quantitys
Inbound port acquires the guide vane opening signal, active power signal and spiral case hydraulic signal of water turbine set respectively；
Step 4：Guide vane opening signal, active power signal and spiral case hydraulic signal in step 3 is adopted by data
A/D conversion modules inside truck are handled, and are converted to digital signal and are inputed to dynamic realtime computing module；
Step 5：Dynamic realtime computing module calculates the active regulating time of water turbine set, the active amplitude of accommodation, active stabilization
Time and the actual integration electricity in primary frequency modulation adjustment process.
Actual integration electricity process of the dynamic realtime computing module calculating in primary frequency modulation adjustment process is in step 5：
It is calculated by the following formula the rotating speed and mains frequency relationship of water turbine set first：
In formula, n is Hydropower Unit rotating speed, and unit is to turn/min, and f is mains frequency, and unit Hz, p are generator magnetic pole
Logarithm；
Then, the theoretical device electricity of primary frequency modulation is calculated according to following formula：
In formula, QtDevice electricity, unit kWh are acted for theory；PrFor unit rated power, unit kW；t0It is one
Secondary frequency modulation starts actuation time, unit s；Δ t primary frequency modulation process durations, unit s；Δ f is the frequency actually measured
Rate deviation, unit Hz；
Finally, the actual integration electricity of primary frequency modulation is calculated according to following formula：
In formula, QrFor actual act device electricity, unit kWh；PtFor unit actual test active power, unit is
kW；P0The practical measurement active power of unit, unit kW before being acted for primary frequency modulation.
Dynamic realtime computing module calculates whether the water turbine set active governing response time is less than 3s, active tune in step 5
Whether section amplitude can reach rated load 10%, whether active adjusting stabilization time is less than 60s, device electricity actual act load
Whether the 50% of theoretical capacity is reached.
The frequency control word K for calculating phase accumulator in step 5 by dynamic realtime computing module, is sent to phase
Phase value is sent in SIN function register after phase accumulator is tired, calculates corresponding signal value, passing through mould by accumulator
Number conversion and low-pass filtering module are exported, then amplify to obtain corresponding required frequency signal to emulate electricity by amplifying circuit
The fluctuation of net frequency.
Data collecting card model PCI-6010, dynamic realtime computing module are PC portable machines, frequency generator model
PCI-5402。
Claims (6)
1. hydroelectric units primary frequency modulation dynamic realtime performance tests system, it is characterised in that：Including data collecting card, the data
AI0 analog inputs port, AI1 analog inputs port and the AI2 analog inputs port of capture card respectively with water turbine set
The port of each sensor connects, and A/D conversion modules and the dynamic realtime computing module pci bus of the data collecting card connect
It connects, the dynamic realtime computing module is connect with frequency generator pci bus, the ports Ctr0 of the frequency generator and water wheels
The governor frequency collection port of unit connects.
2. hydroelectric units primary frequency modulation dynamic realtime performance according to claim 1 tests system, it is characterised in that：It is described
Frequency generator includes high-speed phase accumulator, SIN function register, digital-to-analogue conversion and low-pass filter, wherein high-speed phase
Accumulator, SIN function register, digital-to-analogue conversion and low-pass filter are all connected by the interface of serial input mode.
3. testing the test side of system according to any hydroelectric units primary frequency modulation dynamic realtime performances of claim 1-2
Method, which is characterized in that include the following steps：
Step 1：The frequency control word K that phase accumulator is calculated by dynamic realtime computing module, is sent to phase-accumulated
Phase value is sent in SIN function register after phase accumulator is tired, calculates corresponding signal value, turns by modulus by device
It changes and is exported with low-pass filtering module, amplify to obtain corresponding required frequency signal by amplifying circuit come simulated grid frequency
Fluctuation；
Step 2：Frequency generator realizes Hydropower Unit according to the governor of the undulated control water turbine set of simulated grid frequency
Dynamic primary frequency modulation performance testing experiment；
Step 3：Data collecting card passes through AI0 analog inputs port, AI1 analog inputs port and AI2 analog inputs end
Mouth acquires guide vane opening signal, active power signal and the spiral case hydraulic signal of water turbine set respectively；
Step 4：Guide vane opening signal, active power signal and spiral case hydraulic signal in step 3 is passed through into data collecting card
Internal A/D conversion modules are handled, and are converted to digital signal and are inputed to dynamic realtime computing module；
Step 5：Dynamic realtime computing module calculates the active regulating time of water turbine set, the active amplitude of accommodation, active stabilization time
And the actual integration electricity in primary frequency modulation adjustment process.
4. the test method of hydroelectric units primary frequency modulation dynamic realtime performance test system according to claim 3, special
Sign is that the actual integration electricity process that dynamic realtime computing module calculates in primary frequency modulation adjustment process in step 5 is：
It is calculated by the following formula the rotating speed and mains frequency relationship of water turbine set first：
In formula, n is Hydropower Unit rotating speed, and unit is to turn/min, and f is mains frequency, and unit Hz, p are generator magnetic pole logarithm；
Then, the theoretical device electricity of primary frequency modulation is calculated according to following formula：
In formula, QtDevice electricity, unit kWh are acted for theory；PrFor unit rated power, unit kW；t0Once to adjust
Frequency starts actuation time, unit s；Δ t primary frequency modulation process durations, unit s；Δ f is that the frequency that actually measures is inclined
Difference, unit Hz；
Finally, the actual integration electricity of primary frequency modulation is calculated according to following formula：
In formula, QrFor actual act device electricity, unit kWh；PtFor unit actual test active power, unit kW；P0
The practical measurement active power of unit, unit kW before being acted for primary frequency modulation.
5. the test method of hydroelectric units primary frequency modulation dynamic realtime performance test system according to claim 3, special
Sign is that dynamic realtime computing module calculates whether the water turbine set active governing response time is less than 3s, active tune in step 5
Whether section amplitude can reach rated load 10%, whether active adjusting stabilization time is less than 60s, device electricity actual act load
Whether the 50% of theoretical capacity is reached.
6. the test method of hydroelectric units primary frequency modulation dynamic realtime performance test system according to claim 3, special
Sign is, calculates the frequency control word K of phase accumulator in step 5 by dynamic realtime computing module, and it is tired to be sent to phase
Phase value is sent in SIN function register after adding device, phase accumulator tired, corresponding signal value is calculated, is passing through modulus
Conversion and low-pass filtering module are exported, then amplify to obtain corresponding required frequency signal by amplifying circuit come simulated grid
The fluctuation of frequency.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109638879A (en) * | 2018-12-14 | 2019-04-16 | 国网山东省电力公司电力科学研究院 | Primary frequency modulation dynamic compensation adjustment system and method based on performance indicator assessment |
| CN110487551A (en) * | 2019-09-19 | 2019-11-22 | 贵州电网有限责任公司 | Hydro turbine governor servomotor is failure to actuate time emulation test system and method |
| CN111025071A (en) * | 2019-12-30 | 2020-04-17 | 润电能源科学技术有限公司 | Primary frequency modulation data processing method, device and system |
| CN111896833A (en) * | 2020-08-05 | 2020-11-06 | 贵州电网有限责任公司 | Offline real-time dynamic frequency response test method |
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