Power Plant Automation Series

YXSL-225C digital line protection and measurement device
Scope of Application
The YXSL-225C digital line protection measurement and control device has similar functions to the YXSL-22X digital line protection measurement and control device, in order to be suitable for contact line protection.
protection function
a) Three stage low-voltage blocking direction overcurrent protection;
b) Two low cycle splitting functions;
c) Two section low-voltage disconnection function;
d) Zero sequence current protection function.
Main functional parameters
Quick break protection, delayed quick break protection, overcurrent protection, zero sequence current protection
a) Action value:
Setting range 0.4In~10In; (Zero sequence current is 0~5A)
Grade difference of 0.01A
The accuracy consistency of the action value shall not exceed 3% of the action value; The average error shall not exceed ± 3%
b) Action time:
Setting range 0.01~9.99s
Grade difference of 0.01s
The accuracy of the action time is measured at twice the action current, with a consistency of no more than 20ms and an average action time error of no more than ± 20ms
Phase direction function
Sensitivity angle -30 °, average error not exceeding ± 5 °, consistency not exceeding 5 °
Action zone of 160 °, with an average error not exceeding ± 5 °
When the minimum operating power is online voltage of 0.5V, the maximum sensitivity angle tested should not exceed 0.5VA
Low voltage lockout function
The setting range is 5V~100V, with a setting level difference of 1V and an error not exceeding ± 3%
Low cycle splitting function
a) Low cycle frequency:
Setting range: 46 Hz~50 Hz
Grade difference: 0.01 Hz
Accuracy of action values: Consistency not exceeding 3% of action values, average error not exceeding ± 3%
b) No flow blocking low cycle:
Setting range: 0.1In~10 In
Grade difference: 0.01A
Accuracy of action values: Consistency not greater than 3% of action values, average error not exceeding ± 3%
c) Low cycle disconnection action time:
Setting time: 0.1~9.99s
Grade difference: 0.01s
Accuracy of action time: consistency not exceeding 20ms, average error of action time not exceeding ± 20ms
Low voltage disconnection function
a) Low pressure setting:
Setting range: 5V~100V
Grade difference: 1V
Accuracy of action values: Consistency not exceeding 3% of action values, average error not exceeding ± 3%
b) No current blocking low voltage
Setting range: 0.1In~10 In
Grade difference: 0.01A
Accuracy of action values: Consistency not greater than 3% of action values, average error not exceeding ± 3%
c) Low voltage disconnection action time
Setting time: 0.1~9.99s
Grade difference: 0.01s
Accuracy of action time: consistency not exceeding 20ms, average error of action time not exceeding ± 20ms
zero-sequence protection
a) Action value:
Setting range 0.02A~5A;
Grade difference of 0.01A
The accuracy consistency of the action value shall not exceed 3% of the action value; The average error shall not exceed ± 3%
b) Action time:
Setting range 0.01~9.99s
Grade difference of 0.01s
The accuracy of the action time is measured at twice the action current, with a consistency of no more than 20ms and an average action time error of no more than ± 20ms
c) Zero sequence direction:
90 ° wiring method
Sensitivity angle+90 °
Action zone of 160 °, with an average error not exceeding ± 5 °
When the minimum operating power is online voltage of 0.5V, the maximum sensitivity angle tested should not exceed 0.5VA
Telemetry accuracy
０. Level 5
Remote signaling resolution
No more than 2ms

YXSR-221 Digital Single Channel Measurement and Control Device
Scope of Application
The YXSR-221/2 digital single channel measurement and control device, as a subsystem of substation comprehensive automation, mainly realizes telemetry, remote control, and remote signaling functions.
Main functions
Telemetry function: The measured current is taken from the CT, which can measure a section of bus voltage, a section of transformer voltage used, two DC quantities, one line current, active power, reactive power, frequency, and power factor.
Remote signaling function: The digital signals of the device, as well as signals from circuit breakers, energy storage, isolation switches, remote/local locations, etc., are uploaded to the substation level.
Remote control function: It has 5 sets of output contacts.
Electricity collection function: It has an internal pulse energy collection function, which can collect four channels of pulse electricity.
Bus PT disconnection, insulation monitoring, and control circuit disconnection detection function.
Communicate with the integrated automation system using fieldbus technology, execute downstream commands, and upload measurement data.

YXGB-212 digital generator demagnetization protection device
Scope of Application
The YXGB-212 series digital generator excitation protection device adopts a digital signal processor (DSP) as the core, with modular design, and together with generator differential protection, generator backup protection, and operation box, forms a complete protection system for the generator; Suitable for protecting small and medium-sized generator sets.
protection function
a) Generator demagnetization protection;
b) One point and two-point grounding protection for the rotor;
c) PT disconnection detection;
d) Remote signaling function: Upload switch signals and device digital signals to the substation layer.
Main functional data
Impedance circle constant value range
Impedance ZA setting range 0 Ω~-10 Ω;
Impedance ZB setting range -5 Ω~-80 Ω;
The allowable error for measuring the impedance circle radius is ± 5% or ± 0.15 Ω;
The setting range of action time is 0.1s to 40s;
Apply an excitation amount to ensure the accuracy of the action time, so that the time error of the radius below 0.9 times the set value does not exceed ± 40ms;
The setting range of excitation voltage is 20V~300V, and the allowable error of voltage setting value is ± 5%;
The setting range of negative sequence voltage is 2V~100V, and the allowable error of voltage setting value is ± 5%.
Criteria for demagnetization protection of excitation current
The setting range of excitation current is 20A~100A (corresponding to external input of DC 0.4V~2V or DC 4mA~20mA);
The allowable error of current setting value is ± 5%;
Time setting range: 0.1S~40s;
Accuracy of action time: The average error of action time measured by applying a setting value of 0.9 times or less shall not exceed ± 45ms.
Criteria for demagnetization protection of excitation voltage
The setting range of excitation voltage is 20V~300V;
The allowable error of voltage setting value is ± 5%;
Time setting range: 0.1S~40s;
Accuracy of action time: The average error of action time measured by applying a setting value of 0.9 times or less shall not exceed ± 45ms.
Rotor grounding protection
a) One point grounding protection for rotor
Grounding resistance setting range: 1.00kW~50.00kW;
Accuracy of action values: The average error does not exceed ± 5%;
Time setting range: 1~40s;
Accuracy of action time: The average error of action time does not exceed ± 0.5S.
b) Two point grounding protection for rotor
Second harmonic voltage setting: 1~10V;
Accuracy of action values: The average error above 3V shall not exceed ± 5%; The average error below 3V shall not exceed ± 0.15V;
Time setting range: 0~40s;
Accuracy of action time: The average error of action time measured by applying more than twice the setting value shall not exceed ± 35ms.

YXGP-211 Digital Generator Differential Protection Device
Scope of Application
The YXGP-211 digital generator differential protection device adopts a digital signal processor (DSP) as the core, with modular design, and together with the generator backup protection, generator demagnetization and rotor grounding protection, and operation box, forms a complete protection system for the generator; Suitable for protecting small and medium-sized generator sets.
protection function
a) Phase separated differential quick break protection;
b) Proportional braking longitudinal differential protection;
c) Stator overvoltage protection;
d) Fundamental zero sequence voltage type stator grounding;
e) Third harmonic voltage type stator grounding;
f) CT disconnection detection and differential current over limit alarm function: Real time detection of CT disconnection, can lock differential protection, and alarm when the current suddenly changes but the differential current is large;
Main functional parameters
Differential quick break protection
Setting range: 1~50A;
Accuracy of action values: average error not exceeding ± 3%;
Accuracy of action time: The action time measured at twice the action current should not exceed 25ms.
differential protection
Setting range: 1~50A;
Accuracy of action values: average error not exceeding ± 3%;
Accuracy of action time: The action time measured at twice the action current is not more than 30ms;
Proportional braking: The proportional braking coefficient is 0.10~0.70, and the proportional braking setting is 1~50A.
Stator overvoltage protection
Fixed value of stator overvoltage
Setting range 5V~150V;
Accuracy of action values: The average error does not exceed ± 2.5%.
Stator overvoltage action time
Setting range: 0.1s~9.99s;
The accuracy of action time has an average error of no more than ± 35ms.
Fundamental zero sequence voltage stator grounding
a) Fixed value of fundamental zero sequence voltage
Setting range 1.0V~120V;
The average error of the accuracy of the action value shall not exceed ± 3%.
b) Fundamental zero sequence voltage action time
Setting range: 0.1s~9.99s;
The accuracy of the action time is measured with an average error of no more than ± 35ms at twice the action current.
Third harmonic zero sequence voltage stator grounding
a) Harmonic voltage ratio (K=terminal U3/neutral point U3)
Setting range 0 1 ~ 2.0；
The average error of the accuracy of the action value shall not exceed ± 3%.
b) Third harmonic zero sequence voltage stator grounding action time
Setting range: 0.1s~9.99s;
The accuracy of the action time is measured with an average error of no more than ± 35ms at twice the action current

YXGB-211 digital generator backup protection device
Scope of Application
The YXGB-211 digital generator backup protection device adopts a digital signal processor (DSP) as the core and is designed in a modular manner; Together with generator differential protection, generator demagnetization and rotor grounding protection, and operation box, it forms a complete protection system for the generator; Suitable for protecting small and medium-sized generator sets.
protection function
a) Three stage composite voltage blocking overcurrent protection;
b) Positive sequence current inverse time protection;
a) Negative sequence overcurrent and inverse time limit protection;
b) Single element transverse differential protection/stator current grounding protection;
c) Reverse power protection;
d) Low voltage protection;
e) Low frequency protection;
f) Overfrequency protection;
g) Stator grounding protection (based on zero sequence voltage at the machine end);
h) Stator overload protection;
i) Terminal PT disconnection protection;
Main functional parameters
Three segment composite voltage blocking direction overcurrent protection
Current setting range: 1~99.99A;
Low voltage lockout: setting range 5-100V;
Negative sequence voltage lockout: setting range 5-100V;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Time setting range: 0~12.00s;
Accuracy of action time: The average error of action time does not exceed ± 35ms;
Phase to phase directional sensitivity angle: -30 °, average error not exceeding ± 5 °, consistency not exceeding 5 °
Action zone: 160 °, with an average error not exceeding ± 5 °.
Positive sequence and inverse time limit protection
Current setting range: 1~99.99A;
Time constant range: 0.1~50s;
Inverse time limit:
(Maximum inverse time limit: 120.00 seconds)
Among them: A is the allowable overheating constant of the generator
I1 is the multiple of the positive sequence current of the generator to the fixed value of the positive sequence current
(I1=measured positive sequence current value/positive sequence current constant value)
K is the heat dissipation coefficient (0.01~3.0), and it is recommended that K=1.
Accuracy of action time: The average error of action time does not exceed 5% of the calculated time (when the time is greater than 1 second)
The average error of action time shall not exceed 50ms (when the calculation time is less than 1s).
Negative sequence overcurrent and inverse time limit protection
Negative sequence current setting range: 1~99.99A;
Time constant range: 0.1~50s;
Inverse time limit:
(Maximum inverse time limit: 120.00 seconds)
Among them, A is the constant (0.1~50s) of the rotor surface's ability to withstand negative sequence current
I2 is the multiple of the negative sequence current of the generator to the fixed value of the negative sequence current
K is the heat dissipation coefficient (0.1~3.0)
Accuracy of inverse time limit: The average error of action time does not exceed 5% of the calculation time (when the time is greater than 1 second)
The average error of action time shall not exceed 50ms (when the calculation time is less than 1s).
Single element transverse differential protection/stator current grounding protection
Current setting range: 1~99.99A;
Time setting range: 0~120.00 seconds;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Accuracy of action time: The average error of action time does not exceed ± 35ms.
Reverse power protection
Action zone: Between+90 ° and -90 °, the action interval is not less than 170 °;
Time setting range: 1~120.00 seconds;
Action current: Apply U=UN, and the most sensitive action current should not exceed 50mA;
Accuracy of action time: The average error of action time does not exceed ± 35ms;
Submersible test:
Current creep: U=0, I=10IN, no misoperation Voltage creep: U=UN, I=0, no misoperation.
low voltage protection
Voltage setting range: 5-100V;
Time setting range: 0~120.00 seconds;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Accuracy of action time: The average error of action time does not exceed ± 35ms.
Low frequency protection
Low frequency setting range: 45~50Hz;
Time setting range: 0.1S~120.00s;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Accuracy of action time: The average error of action time does not exceed ± 35mS.
Overfrequency protection
Frequency setting range: 50~55Hz;
Time setting range: 0.1~120.00 seconds;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Accuracy of action time: The average error of action time does not exceed ± 35ms.
Stator grounding protection (based on zero sequence voltage at the machine end)
Voltage setting range: 5-100V;
Time setting range: 0.1~120.00 seconds;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Accuracy of action time: The average error of action time does not exceed ± 35ms.
Stator overload protection
Current setting range: 0.2In~99.99A;
Time setting range: 0~120.00 seconds;
Accuracy of action values: Consistency is not greater than 3% of the action values; The average error shall not exceed ± 3%;
Accuracy of action time: The average error of action time does not exceed ± 35ms.
Terminal PT disconnection
The device can detect PT disconnection and three-phase voltage imbalance.