import math import ezdxf import numpy as np gCAD = None gMSP = None gCount = 1 class Draw: def __init__(self): self._doc = ezdxf.new(dxfversion="R2010") self._doc.layers.add("EGM", color=2) global gCAD gCAD = self def draw(self, i_curt, u_ph, h_gav, h_cav, dgc, color): doc = self._doc msp = doc.modelspace() global gMSP gMSP = msp rs = rs_fun(i_curt) rc = rc_fun(i_curt, u_ph) rg = rg_fun(i_curt, h_cav) msp.add_circle((0, h_gav), rs, dxfattribs={"color": color}) msp.add_line((0, 0), (0, h_gav)) # 地线 msp.add_circle((dgc, h_cav), rc, dxfattribs={"color": color}) msp.add_line((dgc, 0), (dgc, h_cav)) # 导线 msp.add_line((0, h_gav), (dgc, h_cav)) msp.add_line((0, rg), (2000, rg), dxfattribs={"color": color}) # 计算圆交点 # circle_intersection = solve_circle_intersection(rs, rc, h_gav, h_cav, dgc) # msp.add_line((0, h_gav), circle_intersection) # 地线 # msp.add_line((dgc, h_cav), circle_intersection) # 导线 # circle_line_section = solve_circle_line_intersection(rc, rg, h_cav, dgc) # msp.add_line((0, 0), circle_line_section) # 导线和圆的交点 def save(self): doc = self._doc doc.saveas("egm.dxf") # 圆交点 def solve_circle_intersection(rs, rc, hgav, hcav, dgc): # 用牛顿法求解 x = rc # 初始值 y = rc # 初始值 for bar in range(0, 10): A = [[-2 * x, -2 * (y - hgav)], [-2 * (x - dgc), -2 * (y - hcav)]] b = [ x ** 2 + (y - hgav) ** 2 - rs ** 2, (x - dgc) ** 2 + (y - hcav) ** 2 - rc ** 2, ] X_set = np.linalg.solve(A, b) x += X_set[0] y += X_set[1] if np.all(np.abs(X_set) < 1e-5): return [x, y] return [] # 圆与地面线交点 def solve_circle_line_intersection(radius, rg, center_y, center_x): # TODO: 需要考虑地面捕雷线与暴露弧完全没交点的情况 r = (radius ** 2 - (rg - center_y) ** 2) ** 0.5 + center_x return [r, rg] def min_i(string_len, u_ph): u_50 = 530 * string_len + 35 z_0 = 300 # 雷电波阻抗 z_c = 251 # 导线波阻抗 r = (u_50 + 2 * z_0 / (2 * z_0 + z_c) * u_ph) * (2 * z_0 + z_c) / (z_0 * z_c) return r def thunder_density(i): # l雷电流幅值密度函数 r = -(10 ** (-i / 44)) * math.log(10) * (-1 / 44) return r def angel_density(angle): # 入射角密度函数 angle单位是弧度 r = 0.75 * (math.cos(angle - math.pi / 2) ** 3) return r def rs_fun(i): r = 10 * (i ** 0.65) return r def rc_fun(i, u_ph): r = 1.63 * ((5.015 * (i ** 0.578) - 0.001 * u_ph) ** 1.125) return r def rg_fun(i_curt, h_cav): if h_cav < 40: rg = (3.6 + 1.7 ** math.log(43 - h_cav)) * (i_curt ** 0.65) else: rg = 5.5 * (i_curt ** 0.65) return rg def intersection_angle(dgc, h_gav, h_cav, i_curt, u_ph): # 暴露弧的角度 rs = rs_fun(i_curt) rc = rc_fun(i_curt, u_ph) rg = rg_fun(i_curt, h_cav) circle_intersection = solve_circle_intersection(rs, rc, h_gav, h_cav, dgc) # 两圆的交点 circle_line_intersection = solve_circle_line_intersection( rc, rg, h_cav, dgc ) # 暴露圆和补雷线的交点 np_circle_intersection = np.array(circle_intersection) if not circle_intersection: abc = 123 theta2_line = np_circle_intersection - np.array([dgc, h_cav]) theta2 = math.atan(theta2_line[1] / theta2_line[0]) np_circle_line_intersection = np.array(circle_line_intersection) theta1_line = np_circle_line_intersection - np.array([dgc, h_cav]) theta1 = math.atan(theta1_line[1] / theta1_line[0]) # 考虑雷电入射角度,所以theta1可以小于0,即计算从侧面击中的雷 # if theta1 < 0: # # print(f"θ_1角度为负数{theta1:.4f},人为设置为0") # theta1 = 0 return np.array([theta1, theta2]) def distance_point_line(point_x, point_y, line_x, line_y, k): d = abs(k * point_x - point_y - k * line_x + line_y) / ((k ** 2 + 1) ** 0.5) return d def fun_calculus_pw(theta, max_w): w_fineness = 0.01 r_pw = 0 if int(max_w / w_fineness) < 0: abc = 123 pass w_samples, d_w = np.linspace(0, max_w, int(max_w / w_fineness) + 1, retstep=True) for cal_w in w_samples: r_pw += ( ( abs(angel_density(cal_w)) * math.sin(theta - cal_w + math.pi) + abs(angel_density(cal_w + d_w)) * math.sin(theta - cal_w + math.pi - d_w) ) / 2 ) * d_w return r_pw def calculus_bd(theta, rc, rs, rg, dgc, h_cav, h_gav): # 对θ进行积分 # 求暴露弧上一点的切线 line_x = math.cos(theta) * rc + dgc line_y = math.sin(theta) * rc + h_cav k = math.tan(theta + math.pi / 2) # 入射角 # 求保护弧到直线的距离,判断是否相交 d_to_rs = distance_point_line(0, h_gav, line_x, line_y, k) if d_to_rs < rs: # 相交 # 要用过直线上一点到暴露弧的切线 new_k = tangent_line_k(line_x, line_y, 0, h_gav, rs, init_k=k) if not new_k: a = 12 tangent_line_k(line_x, line_y, 0, h_gav, rs, init_k=k) if new_k >= 0: max_w = math.atan(new_k) # 用于保护弧相切的角度 elif new_k < 0: max_w = math.atan(new_k) + math.pi if max_w < 0: abc = 123 tangent_line_k(line_x, line_y, 0, h_gav, rs, init_k=k) global gCount gCount += 1 if gCount % 1000 == 0: # intersection_angle(dgc, h_gav, h_cav, i_curt, u_ph) gMSP.add_circle((0, h_gav), rs) gMSP.add_circle((dgc, h_cav), rc) gMSP.add_line((dgc, h_cav), (line_x, line_y)) gMSP.add_line( (-500, new_k * (-500 - line_x) + line_y), (500, new_k * (500 - line_x) + line_y), ) gMSP.add_line((0, rg), (1000, rg)) gCAD.save() else: max_w = theta + math.pi / 2 # 入射角 r = rc / math.cos(theta) * fun_calculus_pw(theta, max_w) return r def bd_area(i_curt, u_ph, dgc, h_gav, h_cav): # 暴露弧的投影面积 theta1, theta2 = intersection_angle(dgc, h_gav, h_cav, i_curt, u_ph) theta_fineness = 0.01 rc = rc_fun(i_curt, u_ph) rs = rs_fun(i_curt) rg = rg_fun(i_curt, h_cav) r_bd = 0 theta_sample, d_theta = np.linspace( theta1, theta2, int((theta2 - theta1) / theta_fineness) + 1, retstep=True ) for calculus_theta in theta_sample[:-1]: r_bd += ( ( calculus_bd(calculus_theta, rc, rs, rg, dgc, h_cav, h_gav) + calculus_bd(calculus_theta + d_theta, rc, rs, rg, dgc, h_cav, h_gav) ) / 2 * d_theta ) return r_bd # r1=rc*(-math.cos(thyta2)+math.cos(thyta1)) # 入射角密度函数积分 # arrival_angle_fineness=0.0001 # for calculus_arv_angle in np.linspace() def tangent_line_k(line_x, line_y, center_x, center_y, radius, init_k=10.0): # 直线方程为 y-y0=k(x-x0),x0和y0为经过直线的任意一点 # 牛顿法求解k # f(k)=(k*x1-y1-k*x0+y0)**2-R**2*(k**2+1) x1,y1是圆心 # TODO:需要检验k值不存在的情况 k_candidate = [-100, 100] if abs(center_y - line_y) < 1 and abs(line_x - center_x - radius) < 1: # k不存在 k_candidate = [99999999, 99999999] else: for ind, k_cdi in enumerate(list(k_candidate)): k = k_candidate[ind] k_candidate[ind] = None for bar in range(0, 30): fk = (k * center_x - center_y - k * line_x + line_y) ** 2 - ( radius ** 2 ) * (k ** 2 + 1) d_fk = ( 2 * (k * center_x - center_y - k * line_x + line_y) * (center_x - line_x) - 2 * (radius ** 2) * k ) if abs(d_fk) < 1e-5 and abs(line_x - center_x - radius) < 1e-5: # k不存在,角度为90°,k取一个很大的正数 k_candidate[ind] = 99999999999999 break d_k = -fk / d_fk k += d_k if abs(d_k) < 1e-3: dd = distance_point_line(center_x, center_y, line_x, line_y, k) if abs(dd - radius) < 1: k_candidate[ind] = k break # 把k转化成相应的角度,从x开始,逆时针为正 k_angle = [] for kk in k_candidate: if kk == None: abc = 123 # tangent_line_k(line_x, line_y, center_x, center_y, radius) pass if kk >= 0: k_angle.append(math.atan(kk)) if kk < 0: k_angle.append(math.pi + math.atan(kk)) # 返回相对x轴最大的角度k return np.array(k_candidate)[np.max(k_angle) == k_angle].tolist()[-1] def egm(): for u_bar in range(1): u_ph = math.sqrt(2) * 750 * math.cos(2 * math.pi / 6 * 0) / 1.732 # 运行相电压 h_whole = 150 # 杆塔全高 h_gav = h_whole - 0.5 - 11.67 * 2 / 3 h_cav = h_gav - 9.5 - 2.7 - (14.43 - 11.67) * 2 / 3 # 导线对地平均高 dgc = 12 # 导地线水平距离 # 迭代法计算最大电流 i_max = 0 _min_i = 20 # 尝试的最小电流 _max_i = 200 # 尝试的最大电流 for i_bar in np.linspace(_min_i, _max_i, int((_max_i - _min_i) / 0.1)): # 雷电流 print(f"尝试计算电流为{i_bar:.2f}") rs = rs_fun(i_bar) rc = rc_fun(i_bar, u_ph) rg = rg_fun(i_bar, h_cav) circle_intersection = solve_circle_intersection(rs, rc, h_gav, h_cav, dgc) if not circle_intersection: # if circle_intersection is [] continue circle_rc_line_intersection = solve_circle_line_intersection( rc, rg, h_cav, dgc ) min_distance_intersection = ( np.sum( ( np.array(circle_intersection) - np.array(circle_rc_line_intersection) ) ** 2 ) ** 0.5 ) # 计算两圆交点和地面直线交点的最小距离 i_max = i_bar if min_distance_intersection < 0.1: break if circle_intersection[1] < circle_rc_line_intersection[1]: circle_rs_line_intersection = solve_circle_line_intersection( rs, rg, h_gav, 0 ) # 判断与保护弧的交点是否在暴露弧外面 distance = ( np.sum( (np.array(circle_rs_line_intersection) - np.array([dgc, h_cav])) ** 2 ) ** 0.5 ) if distance > rc: print("暴露弧已经完全被屏蔽") break i_min = min_i(6.78, u_ph / 1.732) cad = Draw() cad.draw(i_min, u_ph, h_gav, h_cav, dgc, 2) cad.draw(i_max, u_ph, h_gav, h_cav, dgc, 6) cad.save() # 判断是否导线已经被完全保护 if abs(i_max - _max_i) < 1e-5: print("无法找到最大电流,可能是杆塔较高。") print(f"最大电流设置为自然界最大电流{i_max}kA") print(f"最大电流为{i_max:.2f}") print(f"最小电流为{i_min:.2f}") curt_fineness = 0.1 # 电流积分细度 if i_min > i_max or abs(i_min - i_max) < curt_fineness: print("最大电流小于最小电流,没有暴露弧,程序结束。") return # 开始积分 curt_segment_n = int((i_max - i_min) / curt_fineness) # 分成多少份 calculus = 0 i_curt_samples, d_curt = np.linspace( i_min, i_max, curt_segment_n + 1, retstep=True ) for i_curt in i_curt_samples: cal_bd_first = bd_area(i_curt, u_ph, dgc, h_gav, h_cav) cal_bd_second = bd_area(i_curt + d_curt, u_ph, dgc, h_gav, h_cav) cal_thunder_density_first = thunder_density(i_curt) cal_thunder_density_second = thunder_density(i_curt + d_curt) calculus += ( ( cal_bd_first * cal_thunder_density_first + cal_bd_second * cal_thunder_density_second ) / 2 * d_curt ) n_sf = 2 * 2.7 / 10 * calculus # 调整率 print(f"跳闸率是{n_sf:.6}") # draw(rs, rc, rg, h_gav, h_cav, dgc) if __name__ == "__main__": tangent_line_k(1, 0, 0, 0, 1) egm() print("Finished.")