CN111239485A - A software metering method for self-consumption power of wind turbines - Google Patents

Abstract

The invention discloses a self-power consumption software metering method of a wind generating set, which comprises the following steps: 1) measuring the voltage of the equipment power grid; 2) measuring current; 3) the equipment running state zone bit is a working zone bit; 4) the total self-consumption power of the unit equipment; 5) energy consumption of unit equipment; 6) self-power consumption test and calibration; 7) and (5) curing the parameters. The method can well replace the traditional hardware measurement mode, realizes the unit self-power consumption metering work through a software algorithm, optimizes the start-stop logic of the components through the state monitoring and the self-power consumption condition of each component, and reduces the unit self-power consumption.

Description

A software metering method for self-consumption power of wind turbines

technical field

The invention relates to the technical field of wind generator sets, in particular to a software metering method for self-consumption power of wind generator sets.

Background technique

Currently, wind turbines need to use hardware (voltage sensors and current transformers connected to the power measurement module) to measure the power generation of the unit to measure the total power consumption, but it is impossible to know the self-consumption of each component of the unit. If you want to measure the self-consumption of each component device, you need to add corresponding sensors, which is very expensive and difficult to implement.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies and shortcomings of the prior art, and proposes a software metering method for the self-consumption of wind turbines, which can well replace the traditional hardware measurement method, and realizes the self-consumption metering work of the unit through software algorithms. , and through the status monitoring and self-consumption of each component, the start-stop logic of the components is optimized, and the self-consumption of the unit is reduced.

In order to achieve the above purpose, the technical solution provided by the present invention is: a software metering method for self-consumption power of wind turbines, the wind turbines will inevitably consume a part of energy to meet their own operation requirements during normal operation, and the Part of the consumed energy is called the self-consumption power of the wind turbine, wherein the self-consumption of the wind turbine mainly comes from the power consumption of motors, heaters, fans and PLC module groups; the self-consumption software measurement method includes: The following steps:

1) Equipment grid voltage measurement

The grid voltage U is measured in real time through the main control system of the wind turbine, and the actual voltage of the equipment can be obtained by multiplying the corresponding voltage conversion coefficient by U according to the voltage level of each equipment;

The voltage levels used by the equipment of the wind turbine are mainly divided into 690V, 400V, and 230V, and the conversion relationship of each voltage is: 400V=690V/1.732; 230V=400V/1.732=690V/3;

If the voltage class of the i-th device is 400V, the corresponding device voltage is U _i =U/1.732; if the voltage class of the i-th device is 230V, the corresponding device voltage is U _i =U/3;

2) Current measurement

Use external current test equipment to detect the current value of each component in the unit during operation, record the current value of each component through multiple measurements, and obtain the average current value I _i of each component itself, that is, the operating current of the i-th device; among them, the PLC module The power supply of the group is 24V, and the PLC module group is regarded as a device, then the current value of the PLC module group under the corresponding power supply can be known by measuring the current on the power inlet side of the switching power supply supplying the PLC module group;

3) The device operating status flag, that is, the work flag

When the power grid is in a normal state, the protection switch of the device is in the closed state, and the contactor of the control device is in the pull-in state, it means the device is in a normal working state, and the work flag k _i of the device is set to 1, otherwise the work flag k _i is 0, where _ki represents the working flag bit of the i-th device;

4) The total self-consumption power of the unit equipment

式中，n为设备总数，P_i为第i个设备的自耗电功率；Through steps 1 to 3, you can know the real-time power supply voltage, equipment operating current value and equipment operating status of each device. Through the physical formula P=UI, combined with the equipment operating status, the total self-consumption power of all equipment in the unit can be obtained.

In the formula, n is the total number of devices, and P _i is the self-consumption power of the i-th device;

5) Energy consumption of unit equipment

式中，T_j为第j个周期，

m是指统计周期T共有m个周期T_j；Through the physical formula of energy consumption Q=Pt, in the statistical period T, the total self-consumption of all equipment of the unit is obtained

In the formula, T _j is the jth cycle,

m means that the statistical period T has m periods T _j in total;

6) Self-consumption test and calibration

First, prepare a calibrated power quality tester and install it on the power supply line from the box to the unit equipment;

Secondly, the power quality tester and the unit perform clock synchronization operation to ensure clock synchronization;

Then, when the unit is running, open its main control recording and broadcasting software and the power quality tester to record the total self-consumption power of the unit at each moment;

Use the hardware test energy consumption to compare with the energy consumption calculated by the above formula, and calculate the correction coefficient u;

Finally, the calculation formula of the finalized self-consumption power Q is:

7) Parameter curing

Write the operating current parameters and calibration correction coefficients of each device into the program, and you can see the relevant parameters on the man-machine interface, and transmit the self-consumption of related components and the total self-consumption value of the unit to the main control system of the unit, and then combine The operating state of the unit can optimize the start-stop time of each component to achieve the optimal start-stop logic of the unit, that is, the start-stop logic of each component is optimized by monitoring the status of each component and self-consumption, so as to further reduce the self-consumption of the unit. .

Further, the main control system is integrated with Beckhoff module KL3403 or EL3413, which is used to measure the grid voltage U in real time.

Further, the power quality tester is Fluke1760.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

1. High economic benefits

For the measurement of the self-consumption of the wind turbine, it can replace the hardware measurement method of the drive. Each unit saves 3 current transformer hardware costs and metering modules, and the cost is about 10,000 yuan. One wind farm is based on 33 units, the cost is about 33 Ten thousand.

In addition, the voltage of each device can be obtained by multiplying the voltage level conversion coefficient of the device by the grid voltage, and it is not necessary to install a voltage sensor on each device to measure it.

2. Simple operation, easy promotion and high practicability

It only takes half a day for one unit to complete the test and calibration. Even if the same model of the same wind farm uses the same set of parameters, there is little difference between the calculated value of self-consumption and the measured value of the instrument.

In addition, the power consumption of components can be clearly recorded in real time without using hardware, and the power consumption status of each component of the unit can be clearly defined; by detecting the self-consumption status of each component, the start-stop control logic can be optimized to reduce self-consumption; while traditional The self-consumption of electricity can only measure the total self-consumption, but cannot measure each component of each unit individually.

In a word, the software metering method of the present invention is not limited to doubly-fed models, direct-drive models, and semi-direct-drive models, and the voltage measurement modules applied in the metering method are not limited to differences caused by Beckhoff modules KL3403 or EL3413, etc. Limited to the differences caused by the different equipment used by the unit, it has broad application prospects and is worthy of promotion.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments.

During the normal operation of the unit, it will inevitably consume a part of the energy to meet its own operating needs and ensure the operating needs of the unit itself. This part of the energy consumed is called the self-consumption of the wind turbine, which mainly comes from the motor. , Heater, fan equipment, PLC module group electricity, etc.

Under the condition of stable operation of the unit, the operation of each equipment also tends to be stable, and the operating current during operation is basically unchanged, and the main control system of the unit can monitor the grid voltage in real time and the working status of each equipment, so the energy consumption calculation formula can be used to calculate. The total self-consumption of the unit can be calculated by counting the self-consumption of each device and summing it up.

The software metering method for self-consumption power of a wind turbine provided by this embodiment includes the following steps:

1) Equipment grid voltage measurement

The grid voltage U (690V) is measured in real time through the Beckhoff module KL3403 or EL3413 of the main control system, and then the actual voltage of the equipment is obtained by multiplying the voltage conversion coefficient corresponding to the voltage level of each equipment by U.

The voltage levels used by the equipment of the wind turbine are mainly divided into 690V, 400V, and 230V, and the conversion relationship of each voltage is: 400V=690V/1.732; 230V=400V/1.732=690V/3.

If the voltage level of the i-th device is 400V, the corresponding device voltage is U _i =U/1.732; if the voltage level of the i-th device is 230V, the corresponding device voltage is U _i =U/3.

2) Current measurement

Use external current test equipment to detect the current value of each component in the unit during operation, record the current value of each component through multiple measurements, and obtain the average current value I _i of each component itself, that is, the operating current of the i-th device; among them, the PLC module The power supply of the group is 24V, and the PLC module group can be regarded as a device. Then, by measuring the current on the incoming line side of the switching power supply (400V to 24V) supplying the PLC module group, you can know the PLC module group under the corresponding power supply. current value.

3) The device operating status flag, that is, the work flag

When the power grid is in a normal state, the protection switch of the device is in the closed state, and the contactor of the control device is in the pull-in state, it means the device is in a normal working state, and the work flag k _i of the device is set to 1, otherwise the work flag k _i is 0, where _ki represents the working flag bit of the i-th device (1 for working, 0 for not working).

4) The total self-consumption power of the unit equipment

式中，n为设备总数，P_i为第i个设备的自耗电功率。Through steps 1 to 3, you can know the real-time power supply voltage, equipment operating current value and equipment operating status of each device. Through the physical formula P=UI, combined with the equipment operating status, the total self-consumption power of all equipment in the unit can be obtained.

In the formula, n is the total number of devices, and P _i is the self-consumption power of the i-th device.

5) Energy consumption of unit equipment

式中，T_j为第j个周期，

m是指统计周期T共有m个周期T_j。Through the physical formula of energy consumption Q=Pt, in the statistical period T, the total self-consumption of all equipment in the unit can be obtained

In the formula, T _j is the jth cycle,

m means that the statistical period T has m periods T _j in total.

6) Self-consumption test and calibration

First, prepare a power quality tester calibrated by the national quality inspection agency, such as Fluke1760, and install the Fluke1760 on the power supply line from the box to the unit equipment.

Secondly, Fluke1760 and the unit perform clock synchronization operation to ensure that the two clocks are synchronized.

Then, when the unit is running, open its master recording and broadcasting software and Fluke1760 to record the total self-consumption power of the unit at each moment.

Use the hardware test energy consumption to compare with the energy consumption calculated by the above formula, and calculate the correction coefficient u.

Finally, the calculation formula of the finalized self-consumption power Q is:

7) Parameter curing

Write the operating current parameters and calibration correction coefficients of each device into the program, and you can see the relevant parameters on the man-machine interface, and transmit the self-consumption of related components and the total self-consumption of the unit to the SCADA system of the main control system, and then Combined with the operating state of the unit, the start-stop time of each component is optimized to achieve the optimal start-stop logic of the unit, that is, the start-stop logic of each component is optimized by monitoring the status of each component and self-consumption, so as to further reduce the self-consumption of the unit. Electricity.

To sum up, the method of the present invention can well replace the traditional hardware measurement method, realize the self-consumption measurement of the unit through software algorithms, and optimize the start-stop logic of the components by monitoring the state of each component and the self-consumption situation. , in order to reduce the self-consumption of the unit, its economic benefits are high, the operation is simple, easy to promote, high practicability, it is worth popularizing.

The above-mentioned embodiments are only preferred embodiments of the present invention, and are not intended to limit the scope of implementation of the present invention. Therefore, any changes made according to the shape and principle of the present invention should be included within the protection scope of the present invention.

Claims (3)

1. A self-power consumption software metering method of a wind generating set is characterized in that the wind generating set inevitably consumes a part of energy to meet the self-operation requirement in the normal operation process, the part of consumed energy is called the self-power consumption of the wind generating set, wherein the self-power consumption of the set mainly comes from the power consumption of motors, heaters, fans and a PLC module group; the self-power consumption software metering method is characterized by comprising the following steps of:

1) device grid voltage measurement

The method comprises the steps that a main control system of the wind generating set measures the voltage U of a power grid in real time, and the voltage conversion coefficient corresponding to each equipment voltage grade is multiplied by the voltage U, so that the actual voltage of the equipment can be obtained;

the voltage classes used by the equipment of the wind generating set are mainly divided into 690V, 400V and 230V, and each voltage conversion relation is as follows: 690V/1.732V-400V; 400V/1.732V/3;

if the voltage level of the ith device is 400V, the corresponding device voltage is U_iU/1.732; if the voltage level of the ith device is 230V, the corresponding device voltage is U_i＝U/3；

2) Current measurement

Detecting the current value of each component in the unit during operation by using external current testing equipment, recording the current value of each component through multiple measurements, and obtaining the average current value I of each component_iI.e. the operating current of the ith device; the power supply of the PLC module group is 24V, the PLC module group is regarded as a device, and then the current value of the PLC module group under the corresponding power supply can be known by measuring the current at the power supply inlet side of the switching power supply supplying power to the PLC module group;

3) operating state bits, i.e. working bits

When the power grid is in a normal state, the protection switch of the equipment is in a closed stateWhen the contactor of the control equipment is in the pull-in state, the equipment is in the normal working state, and the working flag bit k of the equipment_iSet to 1, otherwise, work flag bit k_iIs 0, wherein k_iRepresenting the working flag bit of the ith device;

4) total power consumption of a plant

Through the steps one to three, the real-time power supply voltage, the equipment running current value and the equipment running state of each equipment can be known, and the total self-consumption electric power of all the equipment of the unit is obtained through a physical formula P (UI) and by combining the equipment running states

Wherein n is the total number of devices, P_iIs the self-consumption power of the ith device;

5) energy consumption of unit equipment

Obtaining the total self power consumption of all equipment of the unit in the statistical period T by using the physical formula Q of energy consumption as Pt

In the formula, T_jFor the (j) th period of the cycle,

m is the total of m periods T of the statistical period T_j；

6) Self-consuming test and calibration

Firstly, preparing a calibrated electric energy quality tester and installing the tester on a power supply line from a box transformer to unit equipment;

secondly, the electric energy quality tester and the unit perform clock timing operation to ensure clock synchronization;

then, when the unit runs, the main control recording and broadcasting software and the electric energy quality tester are started to respectively record the total consumed electric power of the unit at each moment;

comparing the hardware test energy consumption with the energy consumption calculated by the formula, and calculating a correction coefficient u;

finally, the calculation formula of the self-power consumption Q is shapedComprises the following steps:

7) parametric curing

The running current parameters and the calibration correction coefficients of all the devices are written into a program, relevant parameters can be seen on a human-computer interface, the self power consumption of relevant components and the total self power consumption value of the unit are transmitted to a main control system of the unit, the start-stop time of each component is optimized by combining the running state of the unit, the optimal start-stop logic of the unit is achieved, namely the start-stop logic of each component is optimized by monitoring the state of each component and the self power consumption condition, and the self power consumption of the unit is further reduced.

2. The method for metering the self-consumption software of the wind generating set according to claim 1, characterized in that: the master control system is integrated with a voltage doubling module KL3403 or EL3413 and is used for measuring the power grid voltage U in real time.

3. The method for metering the self-consumption software of the wind generating set according to claim 1, characterized in that: the electric energy quality tester is Fluke 1760.